Energy, Power and Power Management
Transcription
Energy, Power and Power Management
NEW IN THIS ISSUE Developing a BLDC motor-control system? Turn to page 11 now to see the new Circuit Centre feature! Component Focus: pages 3-6 ON Semiconductor’s LC823450 audio-processing SoC helps to reduce development costs Design Notes: pages 7-9 How does a MOSFET turn on? And the key parameters to evaluate when choosing an LDO Circuit Centre: pages 11-15 The best components for a new brushless DC motor design Application Spotlight: pages 16-24 New VIPer0P AC-DC converter consumes almost zero power when in Stand-by mode Application Spotlight on Energy, Power and Power Management Technical View: pages 26-27 How the use of higher-cost SiC power components can reduce total system costs NEWS IN BRIEF INTRODUCTION STAR Industry’s lowest-power ARM Cortex-A5-based MPU features high-grade security capabilities MikroElektronika signs distribution agreement with Future Electronics MikroElektronika, which manufactures a range of development tools and compilers for microcontrollers, has announced a distribution agreement with Future Electronics. Its Click boards support a wide variety of sensors, communication standards and user interfaces, allowing engineers to easily make design prototypes, while linking multiple boards with the mikroBUS™ interface standard. Tools are available for the PIC® and dsPIC® series from Microchip, the AVR® range from Atmel, the PSoC® devices from Cypress Semiconductor and the STM32 line from STMicroelectronics. ‘With Future Electronics as our partner, the availability of our products will increase significantly,’ said Tiziano Galizia, MikroElektronika’s Head of Sales. ON Semiconductor to acquire Fairchild Semiconductor ON Semiconductor and Fairchild Semiconductor International Inc have announced that they have entered into a definitive agreement for ON Semiconductor to acquire Fairchild in an all-cash transaction valued at approximately $2.4bn. The acquisition creates a leader in the power semiconductor market with combined revenue of approximately $5bn, diversified across multiple markets with a strategic focus on automotive, industrial and smartphone end markets. Future Electronics is a franchised distributor worldwide for both companies. ‘Better demand management needed’ in electronics supply chain, Future Electronics conference is told OEMs need to improve the way they manage their demand for electronic components if they are to handle the risks inherent in an increasingly complex supply chain, Alberto Della Chiesa, Vice-President for Supply Chain Solutions at STMicroelectronics told a conference hosted by Future Electronics in Leipzig on 12 November. Some 150 customers of Future Electronics from all over Europe attended the conference, which was dedicated to the theme of ‘Supply Chain Innovation’. It also included visits to Future Electronics’ EMEA Distribution Centre (EMEA DC), one of Europe’s largest stores of electronic components, and to the largest DHL logistics hub in the world, on the site of Leipzig airport. ©Copyright 2016 Future Electronics Ltd. All trademarks contained herein are the property of their respective owners. Applications for product samples, badge boards, demonstration boards, Future Electronics’ boards and other advertised materials from Future Electronics are offered subject to qualification. 160101: 2 For more information e-mail [email protected] PRODUCT ATMEL Atmel has launched a new series of secure Atmel | SMART ARM® Cortex®-A5based microprocessors which offer lower power consumption than any other MPU in its class. Welcome to the first issue in 2016 of FTM, the technology magazine for customers of Future Electronics. The special theme of this issue is ‘Power and Power Management’, a topic of interest to anyone designing an electronics system. In the Application Spotlight section of the magazine in particular, pages 16-24, readers will find a selection of the newest and best parts for power systems. Many of these parts address system designers’ need to reduce the amount of power that their products consume, both in normal operation and when idle. Across every sector of the electronics industry, the requirements of energyefficiency legislation are becoming more stringent. This is nowhere more so than in the field of motor drives: driven by regulations such as the European Commission’s Energy-related Products (ErP) directive, manufacturers of electric motors are having to equip their products with the ability to match their speed and power output to the load, providing for a huge reduction in average power consumption. For many OEMs, the best way to meet the requirements of the ErP directive is to replace legacy fixed-speed motors with a new Variable Speed Drive (VSD) design. The Circuit Centre section on pages 11-15 is dedicated to components that are ideal for use in VSDs. This includes Intelligent Power Modules (IPMs) such as the ON Semiconductor device on page 15: IPMs provide a quick and simple means to implement a motor-drive’s inverter, and they also save board space when compared to discrete inverter circuits. The push for greater power efficiency is also fuelling growing interest in Silicon Carbide (SiC) components: SiC devices achieve lower power losses than silicon-based equivalents, can switch faster and can operate at higher temperatures. In terms of performance and efficiency, then, SiC is far better than silicon as a material for high-voltage power components. The problem with SiC is its cost – but there might be good news on the horizon for designers who want to use SiC components but who are concerned about the impact on their budget. As the market for electric and plug-in hybrid electric vehicles undergoes rapid growth, SiC components will be used in the vehicle’s traction power system and in fast chargers This promises to drive up sales volumes and therefore to reduce unit prices. This could have a knock-on effect on the general electronics market, allowing a far wider range of high-voltage applications to benefit from the efficiency and performance of SiC MOSFETs, diodes and power modules. The BSM180D12P3C007, a SiC power module from ROHM Semiconductor featured on page 18, is an excellent example of the latest generation of SiC power components now available to the electronics industry. Whether your interest is in SiC MOSFETs, IPMs or other new components, FTM presents you with an interesting selection of new parts. Enjoy reading! Paul Donaldson Vertical Markets Director, Future Electronics (EMEA) EMAIL [email protected] FOR SAMPLES AND DATASHEETS The new SAMA5D2 MPUs draw less than 200µA in Retention mode with context preserved and have a fast 30µs wake-up time. In the devices’ new Back-up mode, in which the DDR memory continues to refresh itself, the current is just 50µA. The SAMA5D2 series provides for a high level of system integration, with the addition of a complete audio sub-system and built-in Payment Card Industry (PCI)-level security in miniature Ball Grid Array (BGA) packages with 196, 256 or 289 pins. The series is ideal for applications requiring an entry-level MPU and an extended industrial ambient temperature range of -40°C to 105°C. The new devices also provide an excellent upgrade option for designers currently using ARM926-based MPUs, and who require higher performance, low-power operation, higher security, DDR3 support and a smaller footprint, as well as access to audio and USB functionality and Atmel’s patented SleepWalking™ technology. The robust security system in the new SAMA5D2 MPUs includes the ARM® TrustZone® technology, along with secure boot, hardware cryptography, RSA/ECC capability, on-the-fly encryption/ decryption on DDR and QSPI memories, tamper resistance, memory scrambling, independent watchdog, temperature, voltage and frequency monitoring and a unique ID in each device. Featuring an ARM NEON™ engine, the new SAMA5D2 series’ ARM Cortex-A5 core runs at an operating frequency of 500MHz, providing throughput of 785DMIPS. Its memory system includes a configurable 16- or 32-bit DDR interface controller, 16-bit External Bus Interface (EBI), QSPI Flash interface, ROM with secure and non-secure boot solution, 128kbytes of SRAM, plus 128kbytes of L2 cache configurable as an SRAM extension. The user interface system for the SAMA5D2 includes a 24-bit TFT LCD controller, multiple I2S and SSC/TDM channels, a stereo Class D amplifier and digital microphone support. ENERGY • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Industrial IoT equipment Wearable devices Point-of-sale terminals FEATURES • Floating point unit • Dual CAN-FD controller • 10/100 Ethernet MAC with IEEE 1588 • Two Hi-speed USB ports • One 12-bit image sensor controller with Raw Bayer support • Free Linux distribution • 40 peripheral drivers encoded in C 160102: For samples or pricing e-mail [email protected] WORKING PARTNER CCMOS’ CCS811: page 4 FREE BOARDS STAR PRODUCT The SAMA5D2 Xplained Ultra is a fast prototyping and evaluation platform for the SAMA5D2 series of MPUs. The board includes an ATSAMA5D27-CU MPU and eMMC and DDR3 memories, as well as a rich set of connectivity options. Orderable Part Number: ATSAMA5D2-XULT Apply now at my-boardclub.com Fast-track board request code: FTM61A Atmel’s SAMA5D2: ARM Cortex-A5 core runs at 500MHz Ultra low-power op amps ideal for conditioning PIR sensor signals STMICROELECTRONICS The operational amplifiers in STMicroelectronics’ new TSU10x series draw an extremely low current, enabling designers to optimise their power budget and extend battery lifetime. The TSU101, TSU102 and TSU104 provide accurate signal conditioning of high-impedance sensors; the TSU104 is particularly well suited for use with Passive Infra-Red (PIR) presencedetection sensors. A PIR sensor may be used in a batterypowered system to detect the presence of a person in its field of vision. It is commonly used in security systems, automatic doors and automatic light controls. The TSU104, which integrates four op-amps inside a single package and offers 8kHz of gain bandwidth, can amplify and filter the small signal generated by a PIR sensor. Its tiny 3mm x 3mm package helps to keep the system’s board footprint to a minimum, and thus helps OEMs to reduce bill-of-materials and manufacturing costs. Featuring a no-load current of 580nA per channel, the TSU10x op amps draw less current than is supplied by the typical selfdischarge current of a lithium-ion battery. ST’s STM32L486xx: page 4 WORKING PARTNER NXP’s PCAL6524: page 5 ENERGY • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Ultra-violet and photo-sensors Electrochemical and gas sensors PIR sensors Battery-current sensing Medical instrumentation FEATURES • 5pA maximum input bias current at 25°C • Operating-voltage range: 1.5V to 5.5V • Unity gain stable • Rail-to-rail input and output • 2kV ESD rating according to human body model • Operating temperature range: -40°C to 85°C 160103: For samples or pricing e-mail [email protected] TSU10x op amp: 580nA no-load current per channel VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 3 COMPONENT FOCUS COMPONENT Digital gas sensor offers low power consumption CAMBRIDGE CMOS SENSORS Cambridge CMOS Sensors (CCS) has launched the CCS811, the first digital product in its family of ultra-low-power miniature gas sensors. The CCS811 integrates a metal-oxide gas sensor with a microcontroller sub-system, an ADC and an I2C interface in a single package. Providing an easy-to-use digital measurement of ambient gas concentrations, the CCS811 may be used for indoor air-quality monitoring when embedded in wearables, connectedhome devices, HVAC systems and smartphones. Its highly integrated design makes system implementation easy and helps to reduce billof-materials costs. The internal MCU performs the processor operations required to generate measurements of equivalent CO2 levels or to trigger Volatile Organic Compound (VOC) indicators without intervention by the host system’s processor. The CCS811 can be used to detect ethanol (alcohol) and hazardous gases such as carbon monoxide and a wide range of VOCs. Its unique micro-hotplate sensing technology greatly reduces power consumption when compared to traditional metal-oxide gas sensors, as it provides for very fast cycle and measurement times. The CCS811 is available in a 2.7mm x 4.0mm LGA package. STMicroelectronics has reduced the power required to operate a sophisticated 32-bit microcontroller to a new low level with the introduction of its STM32L4 series of MCUs. The first two microcontrollers in the series, the STM32L476 and STM32L486, feature an 80MHz ARM® Cortex®-M4 core with DSP and floating-point unit. This low-power core is combined in the STM32L4 devices with the ST ART Accelerator™, which provides for zero-wait execution of instructions from Flash. This combination of low-power technologies enables the devices to achieve up to 100DMIPS while drawing just 100µA/MHz. Up to 1Mbyte of dual-bank Flash and 128kbytes of SRAM support sophisticated applications and read-while-write capability. The ultra-low power consumption of these new MCUs has been verified in independent testing against the standard EEMBC™ ULPBench® benchmark: in tests comparing the efficiency of various ultra-low-power microcontrollers, the STM32L476 and STM32L486 scored 123, the best in the industry. 4 INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • • Smart home devices Smart office devices NXP SEMICONDUCTORS FEATURES • <1.2mW average power consumption during active sensor measurement <6µW power consumption in Idle mode Rated for >5 year lifetime • • 160104: For samples or pricing e-mail [email protected] FREE BOARDS The CCS_EVK04_DEV consists of a CCS811 sensor daughter board with I2C interface and an I2C-to-USB bridge board to enable connection to a computer. Windows®-based software is available for sensor measurements and for logging results. Orderable Part Number: CCS_EVK04_DEV Apply now at my-boardclub.com Fast-track board request code: FTM61A CCS811: detects ethanol and hazardous gases Other low-power technologies implemented by ST in the STM32L4 microcontrollers include: • dynamic voltage scaling to balance power consumption with processing demand • the FlexPowerControl architecture • seven power-management modes with submode options. These include Stop, Standby, and Shut-down modes, in which current is as low as 30nA • Batch acquisition mode for efficient data exchange with communication peripherals while in low-power mode The STM32L476 and STM32L486 also feature three 12-bit ADCs operating at up to 5Msamples/s. Hardware oversampling enables the devices to achieve an upscaled 16-bit resolution. NXP’s PCAL6524: page 5 WORKING PARTNER ST’s TSU10x: page 3 Level-shifting I/O expander supports ultra-lowvoltage operation ST’s TSU10x: page 3 WORKING PARTNER Atmel’s SAMA5D2: page 3 32-bit MCUs combine performance and ultra-low energy use STMICROELECTRONICS ENERGY ENERGY INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • • • • Internet of Things devices Industrial equipment Medical equipment Consumer products FEATURES • Two 12-bit DACs • Voltage-reference buffer • Two ultra-low-power comparators • Two op amps • 256-bit AES hardware cryptographic co-processor • Internal RC clock source accurate to ±1% • Digital filter for sigma-delta modulator • 2 ultra-low-power timers 160105: For samples or pricing e-mail [email protected] FREE BOARDS The STM32L4 Discovery Kit combines an STM32L476 MCU with an LCD screen, LEDs, audio DAC, microphone, gyroscope and compass, joystick and connectivity features. It includes an embedded ammeter which measures the MCU’s power consumption in lowpower modes. Orderable Part Number: STM32L476G-DISCO Apply now at my-boardclub.com Fast-track board request code: FTM61A FOLLOW US NOW – SEARCH FTM BOARD CLUB ON FOCUS The PCAL6524 is a 24-bit generalpurpose I/O expander which provides remote I/O expansion suitable for most microcontrollers, via a Fast-mode Plus (Fm+) I2C bus interface. Its ultra-lowvoltage interface allows for direct connection to an MCU operating at a voltage as low as 0.8V. I/O expanders provide a simple solution when additional I/Os are needed while keeping interconnections to a minimum. This is useful, for example, in battery-powered mobile applications for interfacing an MCU to sensors, push buttons and a keypad. In addition to providing a flexible set of GPIOs, the PCAL6524’s built-in level-shifting capability simplifies interconnection of a processor running at one voltage level to I/O devices operating at a different voltage level. The PCAL6524 operates from two supply voltages: one provides the supply voltage for the interface at the master side (for example, to an MCU), and the other provides the supply for core circuits. The PCAL6524 conforms to the Fm+ I2C bus specification at speeds up to 1MHz, and implements Agile I/O features such as: • programmable output-drive strength • latchable inputs • programmable pull-up/pull-down resistors • maskable interrupt • interrupt status register • programmable open-drain or push-pull outputs The device’s outputs can sink 25mA to directly drive LEDs. WORKING PARTNER ST’s STM32L486xx: page 4 ENERGY • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Companion device to a microcontroller FEATURES • 2µA stand-by current at 3.3V • Internal power-on reset • 5.5V-tolerant I/O ports and 3.6V-tolerant I2C bus pins • Noise filter on inputs • 2kV ESD protection according to the human body model 160106: For samples or pricing e-mail [email protected] Advanced audio-processing SoC saves space and power ON SEMICONDUCTOR ON Semiconductor has released its latest high-resolution audio-processing System-on-Chip (SoC), which enables designers to reduce the size and prolong the battery run-time of mobile devices, wearable accessories and voice recorders. design and keep development costs to a minimum. These samples include advanced functions such as noise cancellation, and SLive (Low-frequency Intelligence Virtual Excitation) for enhanced playback of low frequencies. With 1.6Mbytes of on-chip SRAM, the new LC823450 has ample memory for audio processing and application tasks without needing a companion memory chip. Designers can also take advantage of a number of integrated audio peripherals, such as an ADC, a phase-locked loop and a Class D amplifier. In addition, industry-standard interfaces such as SPI, I2C, SDCard and UART enable product designers to provide for connectivity to other system functions. The LC823450 is available in two package styles: a 5.5mm x 5.3mm chip-scale package, and a TQFP measuring 14mm x 14mm. ENERGY The new LC823450 is based on a highly efficient ARM® Cortex®-M3 processor core and ON Semiconductor’s 32-bit/192kHz audioprocessing engine. The audio engine implements MP3 encoding and decoding and wireless-audio support in hardware, which both boosts performance and reduces power usage. In addition, a large selection of royalty- and licence-free DSP code samples are available, which help to accelerate software INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • Digital voice recorders • Wireless headsets • Other portable audio devices • High-resolution audio players FEATURES • I S interface • DSP code for FLAC codec • Hi-Speed USB2.0 device/host interface • Oscillation controller to dynamically 2 change clock frequency 160107: For samples or pricing e-mail [email protected] LC823450: encodes/decodes MP3 files in hardware VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 5 P•I • E COMPONENT DESIGN FOCUS NOTE SECTION Board-to-board connectors absorb large mounting misalignments HIROSE The FX22 series of floating board-toboard connectors from Hirose can absorb mounting misalignment when used in applications in which multiple connectors are found on the same board. The FX22 connector range consists of low-profile headers and receptacles which provide a co-planar board-toboard connection. The header has a unique floating structure embedded inside the housing. This allows movement in the x and z directions of up to ±0.6mm, absorbing mounting misalignments and reducing the risk of mounting failure. Large mating guides on each side of the connector also allow for an alignment movement of ±1.2mm in the x and z directions to simplify the mating operation and to prevent incorrect insertion. The receptacle features double beam contacts. Each beam requires a different contact force to ensure dissimilar vibration characteristics and different resonant frequencies, helping to minimise contact damage and providing for high vibration resistance. Furthermore, the first beam contact has a self-cleaning function which removes dust from the contact path of the second beam contact, thus improving reliability. The popular, high-speed FX18 series boardto-board connectors may be combined with • • • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Industrial equipment Broadcast equipment Smart meters Medical devices Base transmitter stations Measuring instruments Projectors FEATURES Contact sizes: 40, 50, 60, 80 0.7A current rating 0.5mm pitch 50V rating 50 mating cycles 160108: For samples or pricing e-mail [email protected] Hirose’s FX22: first beam contact has a self-cleaning function C&K COMPONENTS C&K has introduced the KSC range of tactile dome-contact switches, which are suitable for use in applications requiring a lifetime rating of as many as 5 million cycles. 6 ENERGY • • • • • Robust, IP67-rated switches can withstand 5 million button presses The switches developed by C&K are the KSC201 J/G LFS, the KSC401 J/G 50SH LFS, the KSC701 J/G LFS and the KSC1001 J/G LFS. These parts give designers a choice of colours, dome sizes and dome styles. All provide positive tactile feedback to the user, and are IP67-rated for protection against moisture and other environmental hazards. the floating FX22 connectors on the same board. In addition, the FX20 series can be combined with the FX22 to provide a vertical or parallel connection. The switches are suitable for surface mounting, and offer J-bend or gullwing-type terminations. The termination material determines the operating temperature rating. Switches with silver terminations are rated for operation at temperatures between -40°C and 85°C. With gold terminations, this range is extended to cover -55°C to 125°C. ENERGY • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Automotive devices Industrial electronics equipment Network infrastructure Computing equipment A guide to the key performance parameters of LDOs INTERSIL A Low Dropout regulator (LDO) is generally thought of as a simple and inexpensive way to regulate and control an output voltage which is produced from a higher input-voltage supply. However, cost and simplicity are not the only reasons for their widespread use. In fact, today’s systems are getting more complex, noise-sensitive and power-hungry. The widespread use of switching power supplies at all power levels means that designers must spend more time avoiding noise-coupling and interference, while improving system efficiency, so cost and simplicity cannot be the only factors affecting power component choices. For most applications, a datasheet’s specifications of basic parameters are clear and easy to understand. Unfortunately, datasheets do not list the parameters for every possible circuit condition. Therefore, to make the best use of an LDO, it is necessary to understand the key performance parameters and their impact on any given load. Designers will need to determine whether the LDO is suitable for a specific load by closely analysing the prevailing circuit conditions. An LDO is comprised of three basic functional elements: a reference voltage, a pass element and an error amplifier. During normal operation, the pass element behaves as a voltage-controlled current source. The pass element is driven by a compensated control signal from the error amplifier, which senses the output voltage and compares it with the reference voltage. Each of these functional blocks affects the LDO’s performance. LDO manufacturers’ datasheets always include specifications that indicate the performance of these functional elements. Dropout voltage Dropout voltage is defined as the difference between the input and output voltages at the point when a further decrease in input voltage causes output voltage regulation to fail. In the dropout condition, the pass element operates in the linear region and behaves like a resistor. For the modern LDO, the pass element is commonly implemented with PMOS or NMOS FETs, which can typically achieve a dropout voltage ranging between 30mV and 500mV. Figure 1 shows the dropout voltage of the ISL80510 LDO, which uses a PMOS FET as the pass element. FEATURES (KSC2 series) • Maximum power: 1VA for silver; 0.2VA for gold • 32V DC maximum voltage • 20mV minimum voltage • Maximum current: 50mA for silver; 10mA for gold • Minimum current: • • • • 1mA for silver; 0.1mA for gold >250V dielectric strength <100mΩ contact resistance >10MΩ insulation resistance <1ms bounce time 160109: For samples or pricing e-mail [email protected] KSC switches: choice of colours, dome sizes and dome styles EMAIL [email protected] FOR SAMPLES AND DATASHEETS Fig. 1: Dropout voltage of Intersil’s ISL80510 Load regulation Load regulation is defined as the output voltage change for a given load change. This is typically from no load to full load: Load regulation indicates the performance of the pass element and the closed-loop DC gain of the regulator. The higher the closed-loop DC gain, the better the load regulation. Line regulation Line regulation is the output voltage change for a given input voltage change, as shown in the following equation: Since line regulation is also dependent on the performance of the pass element and closed-loop DC gain, dropout operation is often not included when considering line regulation. Hence, the minimum input voltage for line regulation must be higher than the dropout voltage. Power-supply rejection ratio The Power-Supply Rejection Ratio (PSRR) is an indication of the LDO’s ability to attenuate fluctuations in the output voltage caused by the input voltage. While line regulation is only considered at DC, PSRR must be considered over a wide frequency range: The PSRR consists of the closed-loop gain, T(s), and the inverse of the openloop transfer function from input to output voltage, 1/Gvg, as shown in Figure 2. While the closed-loop transfer function dominates at lower frequencies, the openloop transfer function from input to output voltage dominates at higher frequencies. Fig. 2: PSRR plotted against frequency Noise This parameter normally refers to the noise on the output voltage generated by the LDO itself, which is an inherent characteristic of the bandgap voltage reference. Most low-noise LDOs need an additional filter to prevent noise from entering the closed loop. Transient response LDOs are commonly used for point-of-load regulation of digital ICs, DSPs, FPGAs and low-power CPUs, where the transient behaviour of the LDO is of high importance. As in all closed-loop systems, the transient response mainly depends on the bandwidth of the closed-loop transfer function. To achieve the best transient response, the closed-loop bandwidth has to be as high as possible while ensuring sufficient phase margin to maintain stability. Although an LDO’s conversion efficiency is lower than that of a Switch-Mode Power Supply (SMPS), in many applications the LDO is to be preferred. In noisesensitive applications, it is difficult for an SMPS to achieve the necessary output ripple to meet a tight noise specification. Fig. 3: Transient response of the ISL80510 Consequently, it is not uncommon (2.2VIN, 1.8VOUT) for an LDO to be added as an active filter to the output of an SMPS. This LDO must have high PSRR at the SMPS’ switching frequency. LDOs are particularly well suited to applications that require an output voltage regulated to slightly below the input voltage. Favourable parameters of ISL80510 For mid- to high-current applications, Intersil’s ISL80510/05 provides balanced performance across all the important LDO performance parameters: low dropout, transient performance, voltage accuracy and a near flat PSRR response across a wide range of frequencies, as shown in Figure 3. For more information e-mail [email protected] 160110: FOLLOW US NOW – SEARCH FTM BOARD CLUB ON 7 DESIGN NOTE DESIGN NOTE Power MOSFETs: understanding the turn-on process VISHAy The question of how to turn on a MOSFET might sound trivial, since ease of switching is a major advantage of fieldeffect transistors. Since MOSFETs are voltage-driven, many users assume that they will turn on when a voltage, equal to or greater than the threshold, is applied to the gate. However, the question of how to turn on a MOSFET or, at a more basic level, what is the minimum voltage that should be applied to the gate, needs reappraisal now that more and more converters are being controlled digitally. While digital control offers flexibility and functionality, the DSPs, FPGAs and other programmable devices with which it is implemented are designed to operate with low supply voltages. It is necessary to boost the final PWM signal to the level required by the MOSFET gate. This is where things can go wrong: many digital designers look at the gate threshold voltage and assume that, just like a logic function, the MOSFET will change state as soon as the threshold is crossed. This assumption, unfortunately, is wrong. In fact, the gate-source threshold voltage value is not even intended for use by system designers. It is the gate voltage at which the drain current crosses the threshold of 250µA. It is also measured under conditions that do not occur in real-world applications. The truth is that the threshold voltage is a MOSFET designer’s parameter. It defines the point at which the device is at the threshold of turning on. In other words, it is an indication of the beginning of the process, and is nowhere near the end of it. Certainly, the gate voltage should be held below the threshold in the off state to minimise leakage current. But for the purposes of turning on the MOSFET, system designers can, and should, ignore the threshold value entirely. So what information should the system designer turn to? A MOSFET datasheet will have a curve which shows the MOSFET turning on with Fig. 2: The SiR826ADP’s output characteristics Fig. 4: SiR826ADP’s gate-charge characteristics Fig. 6: Gate-charge components and timings More important, the curve showing data with the MOSFET fully on is called the output characteristics curve, as shown in Figure 2. Here, the MOSFET’s forward drop is measured as a function of current for different values of the gate-source voltage. System designers may refer to this curve when they wish to ensure that the gate voltage is sufficient. As Figure 2 shows, for each gate voltage at which an on-resistance value is guaranteed, there is a range in which the drain-source voltage drop maintains strict linearity with current, beginning from zero. For lower values of gate voltage, as the current is increased the curve loses its linearity, goes through a knee, and flattens out. A closer view of the output characteristics for gate voltages between 2.5V and 3.6V is shown in Figure 3. MOSFET users usually think of this When confronted with the output characteristics, designers tend to demand to know the on-resistance at their particular operating conditions. Typically it will be at a combination of the gate-source voltage and the drain-source current when the curve has strayed from the straight and narrow into the grey area. In fact, the real key to turning on the MOSFET is provided by the gatecharge curve shown in Figure 4. While this curve is routinely provided in every MOSFET’s datasheet, its implications are not always understood by designers. In addition, recent developments in MOSFET technology, such as trench and shielded gates and charge-compensating superjunction structures, demand a fresh appraisal of this information. Fig. 5: Simplified inductive turn-on circuit To start with, the term ‘gate charge’ itself is somewhat misleading. The linearised and segmented curve does not look like the charging voltage of any capacitor, no matter how non-linear its value. In reality the gate-charge curve represents a superposition of two capacitors which are not in parallel, have different values, and carry different voltages. In the literature, the effective capacitance, Ciss, as seen from the gate terminal is defined as the sum of the gate-source capacitance and the gate-drain capacitance. While this is a convenient entity to measure and specify in the datasheet, it is worth noting that gate charge is not a physical capacitance. It would be a misconception to imagine that the MOSFET is turned on by simply applying a voltage to ‘the gate capacitance Ciss’. Before turn-on, the gate-source capacitance is uncharged, but the gatedrain capacitance has a negative voltage/charge which needs to be removed. Both capacitors are non-linear; their values can vary widely with respect to applied voltage. The switching characteristics, therefore, are dependent more on their stored charges rather than the capacitance value at any given voltage. Since the two component capacitances that make up gate capacitance are physically different and are charged to different voltages, the turn-on process also has two stages. The exact sequence is different for inductive and resistive loads; in most applications, however, the load is heavily inductive and can be described using the circuit model shown in Figure 5. The timing diagram is shown in Figure 6: Fig. 3: Detailed view of the SiR826ADP’s output characteristics Fig. 1: The SiR826ADP’s transfer characteristics increasing gate voltage: the transfer characteristics. This is illustrated for Vishay’s SiR826ADP MOSFET in Figure 1. The transfer characteristics, however, are most useful as a measure of current variation with respect to temperature and applied gate voltage. 8 as the linear mode. However, device designers refer to the grey area as the current saturation region: for the given gate voltage, the current that can be produced has reached its saturation limit. Any increase in applied drain-source voltage will be sustained with only a slight increase in the current, whereas even a slight change in current can lead to a relatively large increase in the drain-source voltage. For higher gate voltages, when the MOSFET has been fully turned on, any operating point will be located in the area shaded in green to the left, marked as the resistive (or ohmic) region. EMAIL [email protected] FOR SAMPLES AND DATASHEETS T0 – T1: gate-source capacitance is charged from zero to the threshold voltage. There is no change in the drain-source voltage or current. T1 – T2: current begins to rise in the device as the gate voltage rises from its threshold value to the plateau voltage. Drain-source current rises from 0A to the full load current, but there is no change in drain-source voltage. The charge associated with it is the integral of the gate-source voltage from 0V to the plateau voltage, and is specified in datasheets as ‘Qgs’. T2 – T3: the flat region between T2 and T3 is also known as the Miller plateau. Before turn-on, the gate-drain capacitance is charged to the supply voltage and holds it until the current has peaked at T2. Between T2 and T3, the negative charge is converted to the positive charge corresponding to the plateau voltage. This is also seen as a fall of the drain voltage from the input voltage to near zero. The charge associated with this is approximately the integral of the gate-drain capacitance from zero to the input voltage, and is specified in datasheets as ‘Qgd’. T3 – T4: as the gate voltage rises from the plateau voltage to the gatesource voltage, there is very little change in the drain-source voltage or current. The effective on-resistance, however, reduces marginally with the rising gate voltage. At some voltage above the plateau voltage, MOSFET manufacturers feel confident enough to guarantee an upper limit to the effective on-resistance. In the real world, then, turning on a MOSFET is not an event but a process. It is not a question of applying a voltage as an input at the gate which will toggle the output from high to low on-resistance. It is the two charges, Qgs and Qgd, injected into the device through the gate pin, which do the job. The gate voltage will rise above the threshold and plateau values in the process, but that is a by-product of the turn-on process. In addition, the speed with which a modern power MOSFET turns on or off is not a simple function of Qgs or Qgd. A detailed study of both the gate-charge curve and capacitance characteristics is necessary to compare switching speeds, especially for superjunction MOSFETs. 160111: FOLLOW US NOW – SEARCH FTM BOARD CLUB ON For more information e-mail [email protected] 9 CIRCUIT CENTRE BLDC Motor Control Interest in implementing Brushless DC (BLDC) motors is growing fast as OEMs respond to the worldwide effort to save energy and resources by adopting efficient, electronically commutated motor types. BLDC motors are one of the most popular choices of new motor technology. Typically up to 10% more power-efficient than common AC motors, BLDC motors are also smaller and lighter, and offer long lifetimes because they have no brushes to wear out. Sophisticated commutation schemes also enable them to rotate at high speed: designers commonly achieve speeds of 20,000rpm using BLDC technology. While BLDC motors can be implemented with a wide range of power ratings, they all share common elements: • a control block using either a dedicated ASSP, a microcontroller or a DSP • a power block using MOSFET or IGBT switching devices • communication, which can be achieved in various ways, including dedicated fieldbuses and Ethernet In addition, sensorless control is possible, but many designers will choose to use a position sensor, as well as isolation barriers where appropriate. Future Electronics’ suppliers have partnered with us to offer their best-in-class parts to fit these functional blocks, featured in this new Circuit Centre section. We hope you enjoy this new section of FTM, and that over time it becomes a useful library of good ideas for you to implement in your designs. Colin Weaving Technology Director, Future Electronics (EMEA) Recommended Parts n POWER SUPPLY Fairchild: FAN7930 Fairchild: FAN6605 STMicroelectronics: L6699 STMicroelectronics: STSR2P n OPTOCOUPLER Everlight: EL071 Everlight: ELS511/611 Fairchild: FOD8314 Fairchild: HCPL2731M n GATE DRIVER Atmel: ATA6831C Fairchild: FOD3150 Intersil: HIP2103/4 Intersil: ISL8003X Vishay: VOW3120 n MCU Atmel: ATmega168PB Atmel: ATSAM E70 Microchip: DSPIC30F6010 NXP: LPC1518JBD100 STMicroelectronics: STM32F100C6T6B n TEMP SENSOR Atmel: AT30TS75A NXP Semiconductors: PCT2075 Microchip: MCP9808 ON Semiconductor: NCT75 n HALL/MAGNETIC SENSOR Crocus: CTSR500 Diodes: AH49 Diodes: AH182P n PHY Microchip: KSZ8091 n IPM Fairchild: FSB50260SF Littelfuse: MG06100S-BN4MM ON Semiconductor: STK5C4U332J-E STMicroelectronics: STGIB15CH60TS-L(E) STMicroelectronics: STGIF10CH60TS-L(E) Vishay: CPV362M4FPbF n POWER FETs Fairchild: FCP220N80 STMicroelectronics: STB15N80KS STMicroelectronics: STW21N150K5 STMicroelectronics: STW12N150K5 n DISCRETE IGBTs Fairchild: FSBB20CH60 Microsemi: APT25GR120BSCD10 DIODES ON Semiconductor: MBR40250 STMicroelectronics: STTH12R06 CAN Transceiver Microchip: MCP2551 NXP Semiconductors: TJA1057GTK ON Semiconductor: NCV7341 Development Tools Future/NXP Semiconductors: FSB1500 STMicroelectronics: P-NUCLEO-IHM001 World’s first 1,500V MOSFETs for safer, greener power A new family of power MOSFETs from STMicroelectronics, the MDmesh™ K5 devices, are the first in the world to combine the benefits of superjunction technology with a very high drain-to-source breakdown voltage of 1,500V. MOSFET 160112: For more information e-mail [email protected] STMICROELECTRONICS ST’s improved superjunction technology offers new high levels of performance, including the lowest on-resistance as a factor of area, the lowest gate charge, and the industry's best Figure of Merit (FoM). The first two members of the MDmesh K5 family are: • the STW12N150K5, with a maximum drain-to-source current of 7A and gate charge as low as 47nC • the 14A STW21N150K5, offering on-resistance as low as 0.9Ω The devices are ideal for electronically commutated motors and all popular power-supply topologies, including standard, quasi-resonant and active-clamp flyback converters, and LLC half-bridge converters. • 4V gate-source threshold voltage For more information • Withstands up to 50V/ns transients e-mail [email protected] • Junction-temperature range: -55°C to 150°C VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 160113: 11 CIRCUIT CIRCUIT CENTRE Temperature sensor achieves Hall-effect sensors provide stable and accurate position data accuracy of ±1°C The AH49 from Diodes Incorporated is a series of small, The PCT2075 from NXP Semiconductors is a temperatureto-digital converter which is accurate to ±1°C over a range of -25°C to 100°C. TEMP SENSOR NXP SEMICONDUCTORS The device can be configured to work as a thermal watchdog, since it includes an open-drain output which becomes active when the temperature exceeds programmed limits. The PCT2075 can be configured for different operating modes. It can be set in Normal mode to periodically monitor the ambient temperature, or in Shut-down mode to minimise power consumption. • Pin-for-pin replacement for LM75 series • Operating temperature range: -55°C to 125°C • <1µA supply current in Shut-down mode versatile linear Hall-effect sensors which are available in SOT23, SC59 and TO92 packages, and with various levels of magnetic-field sensitivity. HALL SENSOR DIODES INCORPORATED The output voltage midpoint is at half of the supply voltage and varies in proportion to the polarity and strength of the magnetic field about this midpoint. This makes the AH49 series ideal for use as position sensors in electronically commutated motors such as brushless DC motors. • Low-noise output • Integrated precision resistors for high temperature stability and accuracy • Low-power operation: 3.5mA current at 5V supply 160116: 160114: For more information e-mail [email protected] For more information e-mail [email protected] Half-bridge driver enables smooth control of DC motors Highly integrated Ethernet PHy includes on-chip low-noise 1.2V regulator Atmel’s ATA6831C is a fully-protected triple half-bridge driver which enables a microcontroller to control a motor in automotive and industrial applications. Microchip’s KSZ8091 is a 10/100 Ethernet physical-layer transceiver (PHY), suitable for transmitting and receiving data over standard CAT-5 unshielded twisted pair cable. ATMEL GATE DRIVER Each of the three highside and three low-side drivers, internally connected to form three half-bridges, can drive currents up to 1.0A. Able to support PWM frequencies up to 25kHz, the ATA6831C can smoothly control two DC motors or a single brushless DC motor. • Supply voltage up to 40V • 0.8Ω on-resistance • 1.0A maximum output current FREE BOARDS Orderable Part Number: ATA6831-DK Apply now at my-boardclub.com Fast-track board request code: FTM61A 160115: For more information e-mail [email protected] Operating at 300MHz, the high-performance SAM E70 ARM® Cortex®-M7 processor-based MCU scores a 1500 CoreMark. MCU ATMEL With up to 2Mbytes of Flash and 384kbytes of SRAM, the device offers tightly linked peripherals which manage events without the intervention of the CPU. The SAM E70 series is pin-compatible with the SAM4E series. • One Ethernet MAC (GMAC) 10/100 Mbps in MII mode and RMII with dedicated DMA • Two master Controller Area Networks (MCAN) with Flexible Data Rate (CAN-FD) • Two 4-channel 16-bit PWMs with comple-mentary outputs • Four 3-channel 16-bit timers/counters • Hi-speed USB host and device with onchip high-speed PHy • Dual 12-bit ADCs and dual 12-bit DACs FREE Bridge drivers deliver long battery life and high reliability Intersil’s HIP2103 and HIP2104 half-bridge drivers significantly extend the battery run-time and overall product life of multi-cell lithium-ion battery-powered devices operating from a supply voltage between 5V and 50V. INTERSIL GATE DRIVER Featuring the industry’s lowest Sleep-mode current and a bridge phase node pin which eliminates any kickback voltage, these half-bridge driver devices are ideal for power tools, home automation products and portable medical equipment in which battery life, longevity and high reliability are required. • 60V maximum bootstrap supply voltage • 5µA quiescent current • Integrated bootstrap FET (emulates the boot diode) FREE BOARDS BOARDS See Board of the Month on page 25 Orderable Part Number: ATSAME70-XPLD Apply now at my-boardclub.com Fast-track board request code: FTM61A 160118: For more information e-mail [email protected] Orderable Part Number: HIP2103-4DEMO1Z Apply now at my-boardclub.com Fast-track board request code: FTM61A 160119: For more information e-mail [email protected] MICROCHIP A highly-integrated PHy, the KSZ8091 uses on-chip termination resistors for the differential pairs, integrates a low-noise regulator to supply the 1.2V core, and offers a flexible, digital I/O interface. The KSZ8091 also provides diagnostic features to facilitate system bring-up and debugging in production testing and in product deployment. • Energy Efficient Ethernet (EEE) support • Wake-On-LAN (WOL) support with either magic packet, link status change, or robust custom-packet detection • Power-down and power-saving modes FREE BOARDS PC-controlled application board 12 PHY 300MHz MCU includes multiple connectivity and analogue features CENTRE Orderable Part Number: KSZ8091RNA-EVAL Apply now at my-boardclub.com Fast-track board request code: FTM61A EMAIL [email protected] FOR SAMPLES AND DATASHEETS 160117: 160120: For more information e-mail [email protected] For more information e-mail [email protected] VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 13 CIRCUIT 32-bit MCU comes with motorcontrol firmware and an on-chip QEI NXP Semiconductors’ LPC1518 microcontroller provides the features and functions needed to quickly and easily implement a high-precision motor-control system. MCU NXP SEMICONDUCTORS Based on the ARM® Cortex®-M3 processor, the LPC1518 has two 12-bit, 12-channel, 2Msamples/s ADCs and an on-chip quadrature encoder interface to enable highly accurate control of both sensored and sensorless motors. Four flexible state-configurable timer/PWM blocks provide up to 28 PWM channels. NXP also offers efficient motor-control firmware, easy-to-use GUI-based tuning tools, and two new motor-control solution kits for the LPC1500 series of MCUs. • Up to 128kbytes of Flash • 20kbytes of SRAM • CAN interface • Real-time clock FREE BOARDS Orderable Part Number: FSB1500 Apply now at my-boardclub.com Fast-track board request code: FTM61A New logic gate optocoupler offers high data rate needed in industrial applications Everlight Electronics’ EL071L is a single-channel logic gate optocoupler offering a data transmission rate of 15Mbits/s. OPTO EVERLIGHT The EL071L consists of an infrared emitting diode optically coupled to a CMOS detector IC, and is ideal for isolating circuit elements in motor drives and other industrial applications. The optocoupler is housed in an 8-pin 4.88mm x 5.85mm x 3.18mm SOP package. • 3.3V and 5V CMOS compatibility • 10kV/µs minimum common-mode transient immunity • 3,750Vrms isolation voltage between input and output • Guaranteed performance from -40°C to 110°C 160121: 160123: For more information e-mail [email protected] For more information e-mail [email protected] Complete development kit for a BLDC motor-control circuit Space-saving optocouplers provide 5,000V isolation STMicroelectronics has released an STM32 motor-control kit based on an X-NUCLEO-IHM07M1 three-phase driver board and a NUCLEO-F302R8 32-bit microcontroller board. Everlight has announced the introduction of two new single-channel optocouplers intended for use in industrial applications. IGBT STMICROELECTRONICS The P-NUCLEO-IHM001 platform provides a complete control solution for a low-voltage, three-phase brushless DC motor. The circuit uses an L6230 driver, a member of the STSPIN family, and an STM32F302R8 microcontroller. The X-NUCLEO-IHM07M1 board is ready to support various control schemes, including closed-loop control, field-oriented commutation or six-step control, in either sensorless or sensor mode. • Operating-voltage range: 8V-48V DC • 2.8A peak output current • Three-phase motor with maximum speed of 19krpm FREE BOARDS Orderable Part Number: P-NUCLEO-IHM001 Apply now at my-boardclub.com Fast-track board request code: FTM61A 14 CIRCUIT CENTRE 160122: For more information e-mail [email protected] OPTO CENTRE Miniature DC-DC buck converters provide 3A continuous output 3A IPM implements complete inverter stage in a single package The new ISL8003x devices from Intersil are DC-DC buck regulators, producing up to 3A of continuous output current from a 2.7V to 5.5V supply. They offer up to 95% peak efficiency. The STK5C4U332J-E is an Intelligent Power Module (IPM) from ON Semiconductor intended for use as an inverter in motor-drive systems. INTERSIL GATE DRIVER IPM The 2mm x 2mm ISL80030, ISL80030A, ISL80031 and ISL80031A, which are pincompatible with each other, all include high-side PMOS and low-side NMOS MOSFETs which have very low onresistance. As well as reducing the need for external components, this also helps to limit power losses. • Typically run without cooling fans or heat-sinks, resulting in improved system reliability • 35µA quiescent current • Internal soft-start and soft-stop FREE ON SEMICONDUCTOR Highly integrated and housed in a single DIP module, it implements a complete inverter stage from a high-voltage DC input to a three-phase IGBT output with a maximum continuous output current of ±3A. It offers under-voltage protection, and internal boost diodes are provided for high-side gate boost driving. All the control-input and status-output signals from the STK5C4U332J-E are at a low voltage compatible with microcontrollers. • Externally accessible embedded thermistor for substrate temperature measurement • Built-in cross-conduction prevention • 150°C maximum junction temperature • 2,000Vrms isolation voltage FREE BOARDS BOARDS Orderable Part Number: ISL8003xDEMO1Z Apply now at my-boardclub.com Fast-track board request code: FTM61A 160125: For more information e-mail [email protected] Orderable Part Number: STK5C4U332JGEVB Apply now at my-boardclub.com Fast-track board request code: FTM61A 160126: For more information e-mail [email protected] EVERLIGHT The 1Mbit/s ELS511 and 10Mbits/s ELS611 are housed in a small 6-pin SOP package measuring 6.8mm x 4.6mm. The devices help users to save PCB space, and are ideal when implementing a size-reduction design. The ELS511 optocouplers consist of an infrared emitting diode, optically coupled to a high speed photodetector transistor. A separate connection for the photodiode bias and output-transistor collector increases the speed by several orders of magnitude compared to conventional phototransistor couplers by reducing the base-collector capacitance of the input transistor. • 5,000Vrms isolation voltage between input and output • Guaranteed performance from 0°C to 70°C • Operating temperature range: -55°C to 100°C EMAIL [email protected] FOR SAMPLES AND DATASHEETS 160127: For more information e-mail [email protected] 160124: For more information e-mail [email protected] VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 15 APPLICATION SPOTLIGHT E N E R G y, Wall-plug AC-DC power supplies comply with new tighter efficiency regulations CUI INC CUI Inc., has announced a new line of wall-plug AC-DC power supplies for the US, Japanese and European markets. The SWI6, SWI12, SWI18 and SWI24, which have either North American or European input blades, meet the stringent average-efficiency and no-load power requirements mandated by the US Department of Energy in its new level VI standard. The aim of this standard is to markedly lower the amount of power consumed when the end application is not in use or is no longer connected to the system. Any manufacturer seeking to market an endproduct with an external adapter in the US must comply with these new provisions by 10 February 2016. The 6W, 12W, 18W and 24W SWI wall-plug adapters all feature a wide universal inputvoltage range of 90-264V AC and are available in single output voltages of 5V, 5.9V, 9V, 12V, 15V or 24V. All models meet the Level VI standard’s no-load power-consumption requirement of <0.1W. Models with input blades for North American and Japanese applications offer UL/cUL and PSE safety approvals, while models with European input blades come with the CE mark. All models also satisfy the requirements of the FCC Part 15 Class B standard for EMI/EMC. ENERGY INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • • • Consumer devices Industrial equipment Portable products FEATURES • • • • • • 300,000 hours’ MTBF ±5% typical regulation Over-voltage protection Over-current protection Short-circuit protection 0.25mA maximum leakage current 160128: For samples or pricing e-mail [email protected] CUI’s SWI series: supplied with North American or European input blades Light-load algorithm improves efficiency of DC-DC buck converters DIODES INCORPORATED Two new synchronous DC-DC buck converters introduced by Diodes Incorporated offer highly efficient operation at both full and light loads. The 1.5A AP65101 and 2A AP65201 achieve efficiency of up to 97% at their maximum continuous current. They benefit from a low quiescent supply current and integrated high- and low-side switches with low on-resistance, which helps to reduce conduction losses. At the same time, the new AP65x01 devices offer excellent efficiency at low loads because of an automatic light-load algorithm, which is triggered when the inductor’s peak current falls below a pre-set threshold. 16 The AP65101 and AP65201 buck converters are intended for low-voltage regulation, especially in distributed power architectures. They operate from an input-voltage range of 4.5 to 16V, producing an adjustable output voltage in a range from 0.8V up to 80% of the input voltage. The converters’ high level of integration and minimal need for external components combined with the small footprint of the TSOT26 package provide valuable cost and board-space savings. Current-mode operation enables fast transient response and easy loop stabilisation. The device’s Enable pin has a high voltage tolerance of up to 6V. ENERGY • • • • • • • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Point-of-load power supplies Consumer electronics devices Set-top boxes Coffee machines Access points and gateways Modems FEATURES 500kHz switching frequency Over-current limit Over-voltage protection Under-voltage lock-out Thermal shut-down protection 160129: For samples or pricing e-mail [email protected] POWER & POWER MANAGEMENT New chip clamps down on vampire power in appliances, lighting and industrial equipment STMICROELECTRONICS The phenomenon of ‘vampire power’ – the energy used by equipment which is standing idle – could be about to end thanks to the latest power-supply chip from STMicroelectronics. The new VIPer0P AC-DC power converter from ST can drive down stand-by power consumption to 5mW while fed by a 230V AC supply. This is rounded to zero according to the IEC 62301 standard for household and office appliances. The converter is also the first in the world to provide a smart way of managing the wake-up function. In the VIPer0P, ST has introduced a patented smart-management capability not offered by any other converter in the market: because it is able to provide stand-by power for the host microcontroller while in Idle mode, the system may be woken via the main appliance’s user interface, such as a touchscreen or remote control. This means that there is no need for a dedicated high-voltage mechanical switch to take the appliance out of Stand-by mode. If a switch is used to control stand-by operation, Idle power can be reduced even more, to 4mW. Switching can be performed at Safety Extra-Low Voltage (SELV) levels, eliminating the need for bulky high-voltage components. VIPer0P may be configured as a flyback, buck, or buck-boost switched-mode power supply. It integrates an avalanche-rugged power MOSFET with a breakdown voltage of 800V, giving designers a high safety margin for superior reliability. Other features include integrated highvoltage start-up circuitry, and a sense-FET for energy-efficient current sensing. In addition, VIPer0P’s self-supply design simplifies transformer selection by eliminating the need for an auxiliary winding. ENERGY • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Home appliances Home automation Industrial equipment Lighting Consumer devices FEATURES • Current-mode PWM controller • Over-current protection • Jittered switching frequency reduces EMI filter cost • Embedded error amplifier with 1.2V reference • Pulse-skip protection to prevent flux • runaway Embedded thermal shut-down 160130: For samples or pricing e-mail [email protected] FREE BOARDS This evaluation kit demonstrates a 7W dual-output (7V/-5V) flyback converter with a non-isolated topology, based on the VIPer0P off-line converter IC. Orderable Part Number: STEVAL-ISA174V1 Apply now at my-boardclub.com Fast-track board request code: FTM61A ST’s VIPer0P: supports flyback, buck and buck-boost topologies Efficient 600V MOSFETs reduce effects of gate loop inductance VISHAy Vishay Intertechnology has extended its 600V E series of power MOSFETs with new devices housed in its compact PowerPAK® 8mm x 8mm package, providing a space-saving alternative to conventional TO-220 and TO-263 solutions. The new Vishay Siliconix SiHH2xxN60E parts feature a large drain terminal for low thermal resistance. In addition, the construction of the PowerPAK® 8x8 package allows one of the source pins to be arranged as a dedicated Kelvin source connection which separates the gate-drive return path from the main current-carrying source terminals. This prevents the voltage drop in the high-current path attributable to gate loop inductance from reducing the gate-drive voltage applied to the MOSFET. This in turn leads to faster switching and better noise immunity in high-performance power-supply designs. Based on Vishay's latest energy-efficient E series superjunction technology, the SiHHxxN60E devices offer low on-resistance and gate charge. These values result in extremely low conduction and switching losses, helping reduce energy consumption in power factor correction circuits, flyback converters, and two-switch forward converters. They are designed to withstand high energy pulses in the avalanche and commutation modes. Part Number Drain-source Voltage (V) Gate-source Voltage (V) Drain Current (A) at 25°C Maximum On- Typical Gate resistance (Ω) Charge (nC) at at 10V 10V Typical Gate Capacitance (pF) SiHH26N60E 600 ±30 25 0.135 77 2815 SiHH21N60E 600 ±30 20 0.176 55 2015 SiHH14N60E 600 ±30 16 0.228 41 1416 SiHH11N60E 600 ±30 11 0.339 31 1076 ENERGY • • • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Server and telecoms power supplies HID and fluorescent lighting ballasts Power adaptors Motor drives Solar PV inverters Induction heating Welding equipment FEATURES (SiHH26N60E) • 353mJ maximum pulse avalanche energy • 0.48°C/W junction-to-case thermal resistance • Junction-temperature range: -55°C to 150°C 160131: For samples or pricing e-mail [email protected] AP65x01: valuable cost and board-space savings FOLLOW US NOW – SEARCH FTM BOARD CLUB ON VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 17 APPLICATION SPOTLIGHT Highly efficient DC-DC converter steps down 5V rails to supply points-of-load INTERSIL Intersil has released a highly integrated synchronous buck regulator which steps down 5V rails to Point-of-Load (PoL) inputs as low as 0.6V, suitable for FPGAs, DSPs and microprocessors. The feature-rich ISL8018 provides up to 8A of continuous output current from a 2.7V to 5.5V input supply, while offering up to 97% efficiency and higher integration than competitive devices. The 3mm x 4mm regulator provides an innovative SyNCIN and SyNCOUT feature which connects and synchronises multiple regulators at the same switching frequency in a master/slave configuration, using a phase-shifting time delay. This prevents On-time overlapping and reduces average current, ripple and inputcapacitance requirements, which serves to reduce electro-magnetic emissions and to improve efficiency. The ISL8018 also provides for voltage output margining to be set at ±10% to compensate for output-voltage drops in reverse-current conditions. The switching frequency is programmable in a range from 500kHz to 4MHz, enabling the use of small passive components for faster transient response and board-space saving. E N E R G y, ENERGY INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • Point-of-load modules • Power supplies for microcontrollers, processors, FPGAs and DSPs • DC-DC converter modules • Portable instruments • Test and measurement systems • Li-ion battery-powered devices FEATURES • Complete converter occupies less than 97mm footprint 2 • Adjustable current limit • Start-up with pre-bias output and internal soft-start • Peak-current limiting • Hiccup-mode short-circuit protection 160132: For samples or pricing e-mail [email protected] FREE BOARDS The ISL8018EVAL3Z evaluation board is intended for point-of-load applications sourcing from 2.7V to 5.5V. Orderable Part Number: ISL8018EVAL3Z Apply now at my-boardclub.com Fast-track board request code: FTM61A ISL8018: enables synchronisation of multiple regulators at the same frequency New SiC power module offers hugely improved switching performance ROHM SEMICONDUCTOR ROHM Semiconductor has introduced a new 180A Silicon Carbide (SiC) power module which benefits from the dramatic reduction in on-resistance provided by the double-trench structure of its latest SiC MOSFETs. concentrated at the base of the gate trench, lowering the electrical stress on the device compared to a MOSFET with a conventional single-trench structure. ROHM has also expanded its line-up of full SiC power modules with the new 1,200V/300A BSM300D12P2E, adding to the 120A/180A devices already available. The new module is suitable for large power supplies in industrial equipment, providing much reduced switching losses when compared to conventional silicon IGBT power modules. The BSM180D12P3C007 module is a 1,200V/180A full SiC power module which includes third-generation SiC trench MOSFETs. In the new MOSFETs, on-resistance is cut in half by comparison with the previous generation of SiC MOSFETs, which have a planar structure. Input capacitance in the new devices is some 35% lower. As a result, switching losses in the new BSM180D12P3C007 module are reduced by 42% compared to the ROHM BSM180D12P2C101 module, which contains planar MOSFETs. The new double-trench structure also enhances the long-term reliability of the new module, since it diffuses the electric field • • • • NXP SEMICONDUCTOR NXP Semiconductor’s new PCA9410 and PCA9410A are highly efficient 3MHz step-up (boost) DC-DC converters. They convert input voltages ranging between 2.5V and 5.25V to a fixed output voltage of 5.0V. The output current limit is 500mA. These 1.2mm x 1.2mm devices are optimised for battery-powered applications: high conversion efficiency of up to 94% helps to provide for extended battery life in any portable product design. In addition, the devices’ switching frequency of 3MHz enables the use of a small inductor with a value of 1µH or less. The PCA9410 devices offer tightly controlled regulation, LIGHTING MEDICAL AUTOMOTIVE SECURITY Motor drives Inverters Power converters Induction heating equipment STMicroelectronics’ ST1S15 is an efficient step-down converter which provides an output current of up to 500mA from an input voltage ranging between 2.3V and 5.5V. case temperature • Junction-temperature range: -40°C to 175°C • 2,500V AC isolation voltage (1 minute) • 10mΩ typical on-resistance at an 18V gate-source voltage, drain current of 180A and a junction temperature of 25°C FOLLOW US NOW – SEARCH FTM BOARD CLUB ON providing output voltage accuracy of ±2% at nominal and static conditions. Even over the full current, voltage and temperature range, the output is accurate to within ±3%. The PCA9410 totally disconnects the input from the output when disabled. The PCA9410A connects the input to the output when disabled. 6MHz, 500mA step-down converter offers valuable system space saving FEATURES (BSM180D12P3C007) 160133: MANAGEMENT ENERGY • • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS NFC terminals FEATURES Current-mode controller Soft-start function Reverse-current protection Over-current protection Over-temperature protection For samples or pricing e-mail [email protected] PCA9410: fixed 5.0V output voltage for use in NFC terminals CONSUMER TELECOMMS APPLICATIONS POWER 160134: • 180A maximum drain current at a 60°C SiC power modules: lower electrical stress for long lifetime 18 INDUSTRIAL & 500mA DC-DC boost converter provides accurate regulation STMICROELECTRONICS ENERGY POWER For samples or pricing e-mail [email protected] The converter’s main benefits are its high efficiency, typically 85%, and the small footprint of the complete power-conversion circuit. Thanks to its high 6MHz switching frequency, the ST1S15 can operate with small supporting components: an inductor with a nominal value of 470nH, and an output capacitor of just 4.7µF. At the same time, the ST1S15 produces a very fast and accurate response to load and line transients. The converter can operate in Pulse Frequency Modulation mode, for the highest efficiency under light-load conditions, or PWM mode for tight regulation and the best dynamic performance. ENERGY INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • Power supplies for DSPs and multimedia • • • • • • • processor cores Mobile phones PDAs FEATURES 45µA quiescent current -1.5% typical regulation 10mV output-voltage ripple in PWM mode Short-circuit protection Thermal protection 160135: For samples or pricing e-mail [email protected] ST1S15: very small supporting components for space-saving designs VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 19 APPLICATION SPOTLIGHT E N E R G y, Automotive buck converter provides adjustable output voltage ON SEMICONDUCTOR The NCV894530 from ON Semiconductor is a DC-DC buck converter IC intended for use in automotive driverinformation systems that operate from a downstream voltage rail. It implements a synchronousrectification conversion scheme for high efficiency. The output voltage is externally adjustable in a range from 0.9V to 3.3V, and can source up to 1.2A. The converter runs at a switching frequency of 2.1MHz, avoiding interference with the sensitive AM radio band, and enabling the use of a small inductor. The NCV894530 provides various features expected in automotive power systems, such as integrated soft-start, hiccup-mode current limit, and thermal shut-down protection. The device can also be synchronised to an external 2.1MHz clock signal. The NCV894530 is available in the same 3mm x 3mm 10-pin DFN package as the dual NCV896530, with a compatible pin-out. ENERGY • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY APPLICATIONS Automotive audio systems Automotive infotainment systems Automotive instrumentation FEATURES external clock AEC-Q100 qualified 160136: For samples or pricing e-mail [email protected] NCV894530 buck converter: avoids interference with AM radio band Three new solid-state relays offer current-limit protection and high isolation VISHAy Vishay Intertechnology has introduced the first three devices in its new VOR family of hybrid solid-state relays, which offer noiseless switching and provide higher reliability and a longer lifetime than traditional electro-mechanical relays. The new 1 Form A VOR1142 relays are notable for their high input-to-output isolation, currentlimit protection and low power consumption. They are normally-open single-pole, single-throw switches. Allowing for simple customisation, the devices feature a modular construction consisting of a gallium aluminium arsenide infra-red actuation control, and MOSFETs for the switch output. The single-channel relays are offered in three package options: • DIP-6: VOR1142A6 • SMD-6: VOR1142B6 • SOP-4: VOR1142M4 Devices in the SMD-6 and DIP-6 packages have high isolation voltage rating of 5,300V/1 minute, while devices in the smaller SOP-4 package are rated for 3,750V/1 minute. Electronically isolated, the VOR1142 relays offer clean, bounce-free switching over an ambient temperature range of -40°C to 100°C. The devices are VDE and UL certified to meet the reinforced insulation requirements of most applications. ENERGY • • • • • • • • • • • • INDUSTRIAL LIGHTING MEDICAL CONSUMER TELECOMMS APPLICATIONS Telecoms power supplies Metering equipment Security equipment Instrumentation Industrial controls Battery-management systems Automatic measurement equipment FEATURES 22Ω on-resistance 140mA load current 400V load voltage 0.25mA turn-on current High surge capability 160137: For samples or pricing e-mail [email protected] VOR family: high input-to-output isolation 20 AUTOMOTIVE SECURITY EMAIL [email protected] FOR SAMPLES AND DATASHEETS & POWER MANAGEMENT Synchronous rectification controller ideal for LLC resonant converters A low-power mode reduces the current through the converter in light-load and no-load conditions to a typical 50µA. STMICROELECTRONICS CONSUMER TELECOMMS • Input voltage range: 2.7V to 5.5V • 1mA quiescent current (no switching) • Short-circuit protection • Internal MOSFETs • Automatically synchronises with an • POWER The SRK2001 from STMicroelectronics is a power controller which implements a control scheme specifically intended for secondary-side synchronous rectification in LLC resonant converters. It provides two high-current gate-drive outputs, each capable of driving one or more N-channel power MOSFETs. Each gate driver is controlled separately, and an interlock logic circuit prevents the two synchronous rectifier MOSFETs from conducting simultaneously. When used to implement synchronous rectification in LLC resonant converters, the SRK2001 requires very few external components. The control scheme in this IC provides for each synchronous rectifier to be switched on as the corresponding half-winding starts conducting, and switched off as its current falls to zero. The innovative turn-on logic with adaptive masking time, and the adaptive turnoff logic, have the effect of prolonging the time during which the MOSFETs are conducting: this eliminates the need for a circuit to compensate for parasitic inductance. ENERGY • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS AC-DC adapters High-end flat-panel TVs Servers Industrial equipment FEATURES • Operating-voltage range: 4.5V to 32V • High voltage drain-to-source Kelvin • • • sensing for each MOSFET Up to 500kHz switching frequency 35ns total delay at turn-off Protection against current reversal 160138: For samples or pricing e-mail [email protected] FREE BOARDS The STEVAL-ISA170V1 is a 150W converter tailored to a typical specification for an all-in-one computer power supply or a high-power adapter. This highly efficient power supply complies with the Energy Star eligibility criteria for adapters and computers. Orderable Part Number: STEVAL-ISA170V1 Apply now at my-boardclub.com Fast-track board request code: FTM61A SRK2001: two high-current gate-drive outputs New external power supplies eliminate power risks in home healthcare equipment SL POWER SL Power Electronics has introduced its newest family of medical-grade external power supplies, the 60W ME60 series for home healthcare equipment. The new ME60 models meet the requirements of the IEC 60601-1-2 Fourth edition EMC standard. They are also approved to AAMI ES/CSA C22.2/EN/IEC 60601-1, third edition with two Means Of Patient Protection (MOPP). As well as achieving full medical certification, the ME60 external power supplies also address the need for high efficiency, complying with the new US Department of Energy’s level VI efficiency standard. These new models are specifically designed for next-generation home healthcare devices such as surgical and patient-monitoring equipment, and therapeutic electro-medical devices, which require a high level of EMC, EMI and AC-input performance. The feature-rich power supplies use highquality electrolytic capacitors, which provide for a product life of more than seven years. In addition, the ME60 series power supplies are characterised by low common-mode noise, and high levels of ESD (to IEC 61000-4-2, level 4 standard: 8kV/15kV) and surge protection (to IEC 61000-4-5, level 4 standard). The ME series offers a mean time between failure of longer than 250,000 hours. In addition, with many input connection types (IEC 60320 C14, C8 or C18 grounded or ungrounded cord set) these models can be used anywhere in the world. Housed in an impact-resistant IP22-rated polycarbonate enclosure, the desktop models offer regulated output power with low ripple, no-load power consumption of less than 0.21W, and short-circuit and thermal protection. The power supplies comply with the EN55011/CISPR11, FCC Part 15.109 Class B standard for conducted and radiated emissions with a 6dB and 3dB margin respectively. ENERGY • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Medical equipment FEATURES • Input-voltage range: 90V to 264V AC • Operating-temperature range: 0°C to 50°C • Three-year warranty 160139: For samples or pricing e-mail [email protected] SL Power ME60: multiple input connection options VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 21 APPLICATION SPOTLIGHT E N E R G y, Automotive designers benefit from higher power density with new dual MOSFETs ENERGY LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS • Engine and transmission controllers • Braking solenoid and motor drives • Space-constrained automotive switching NXP Semiconductors has extended its portfolio of automotive power MOSFETs in the LFPAK56D package, which has a Power-SO8 footprint. The new BUKxK line of devices increases power density by fitting two MOSFETs into a single, robust package without impairing performance. In fact, the new dual MOSFETs are fully AEC-Q101-qualified for operation at temperatures up to 175°C. Designers using the LFPAK56D products can reduce the footprint-per-MOSFET-channel by 77% compared to DPAK devices, and by 56% compared to single LFPAK56 devices. The new dual MOSFET packages are available with maximum voltage ratings of 30V, 40V, 60V and 100V. The LFPAK56D package’s copper clip design eliminates the need for wire bonds. INDUSTRIAL applications FEATURES • High maximum drain-current ratings • Low package resistance and inductance • Low thermal resistance • Footprint compatible with other Power• • S08 packages Excellent tolerance of high transient currents 100% avalanche tested 160140: For samples or pricing e-mail [email protected] NXP dual-MOSFET package: operates at up to 175°C & POWER MANAGEMENT Efficient external AC-DC power supply complies with new level VI standard SL POWER NXP SEMICONDUCTOR POWER SL Power Electronics’ new TE60 series is a 60W external power supply which complies with the US Department of Energy’s new level VI efficiency standard. The TE60’s high-performance design makes it an ideal solution for use with handheld test and measurement equipment and industrial devices, in which low noise and rugged performance are required. It is available in models with an output voltage of 5V, 12V, 15V, 18V, 24V or 48V. The TE60 series also offers strong EMC performance, meeting the requirements of the industrial-grade EN61000-4-X standard, which protects end-use equipment from harsh electrical environments. Moreover, the TE60 series uses high-quality electrolytic capacitors, providing for a product life of longer than seven years. Low common-mode noise, level 4 ESD protection (compliant with IEC 61000-4-2: 8kV/15kV) and surge protection (compliant with IEC 61000-4-5: 1kV differential mode/4kV common mode) help to ensure the highest overall performance. The TE60 power supplies offer regulated output power with low ripple, no-load power consumption of less than 0.21W, and shortcircuit and thermal protections. They meet the requirements of the EN55011/CISPR11, FCC Part 15.109 Class B standard for conducted and radiated emissions with a 6dB and 3dB margin respectively. The TE60 features convenient IEC 60320 C14 grounded or C8 ungrounded inputconnector options which can accept input line cords with any appropriate plug configuration. ENERGY • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Test and measurement equipment Industrial equipment FEATURES • Input-voltage range: 90-264V AC • Three-year warranty • Approved to EN/IEC/UL 60950-1, 2nd Edition, Am. 2 • <1s turn-on time at 115V AC • >20ms hold-up time • ±5.0% total regulation • Operating temperature range: -20°C to 50°C 160142: For samples or pricing e-mail [email protected] SL Power’s TE60 series: no-load power consumption below 0.21W Easy-to-configure controllers simplify digital power conversion STMICROELECTRONICS The STNRG digital-controller family from STMicroelectronics provides an easy way for designers to implement an efficient digital power-conversion system with enhanced safety features and generous provision of diagnostic information. 160141: 22 For more information e-mail [email protected] EMAIL [email protected] FOR SAMPLES AND DATASHEETS The rugged STNRG ICs contain ST’s unique State Machine Event Driven (SMED) highresolution PWM generator, together with an 8-bit supervisory controller core. The SMED circuitry is a proven method for implementing high-performance digital control in STLUX ICs for LED lighting. The STNRG parts also include a 32kbyte EEPROM, 6kbyte RAM, an ADC, op amp, I2C port and general-purpose I/Os. Configuring the SMED calls for no specialist software expertise, unlike the usual DSP- or microcontroller-based approaches to digital power control. ENERGY • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS High-end industrial applications Solar-power converters Electric-vehicle charging stations Industrial switched-mode power supplies FEATURES The SMED can be triggered from the internal timer or by an external event such as peak current, over-current or zero crossing. This enables a peak-current detecting buck converter, with constant off-time set by the timer, to operate without intervention by the core processor. A simple proportional-integral loop executed in the core sets the peak-current value for output regulation. The STNRG family is comprised of the STNRG288A with four SMED-controlled outputs, the STNRG328A with five SMED outputs, and the STNRG388A with six SMED outputs. Designers have the option to connect two SMED cells together to generate dual gate-drive signals with inserted dead time for half-bridge configurations. WORKING PARTNER ST’s STD16N60M2: page 24 • Four analogue comparators • <50ns propagation delay • Internal 96MHz PLL • System, auxiliary and basic timers • Multiple low-power modes • UART interface • I C master/slave interface • Operating-temperature range: 2 -40°C to 105°C 160143: For samples or pricing e-mail [email protected] FREE BOARDS The EVLSTNRG-170W evaluation board is intended for evaluating the STNRG388A digital controller in off-line power-conversion applications. The board implements a PFC stage followed by a resonant LLC stage, supplying a load of up to 170W. Orderable Part Number: EVLSTNRG-170W Apply now at my-boardclub.com Fast-track board request code: FTM61A VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 23 APPLICATION SPOTLIGHT New power MOSFETs get close to perfect switching performance STMICROELECTRONICS STMicroelectronics has extended its popular MDmesh™ M2 series of N-channel power MOSFETs with the introduction of a new family of devices which offer the industry’s highest power efficiency, especially under light-load conditions. Ideal for both hard- and soft-switching topologies, including resonant topologies such as LLC, the new devices offer extremely low switching losses, especially under light-load conditions. In addition to the very low gate charge found in all MDmesh M2 devices, the M2 EP devices also feature up to a 20% reduction in BOARDS turn-off energy, thus reducing by the same percentage the turn-off switching losses in hard-switching converters. This reduction in the low-current range boosts efficiency under light-load conditions, where efficiency reuglations are becoming increasingly demanding. The enhanced shape of the turn-off waveforms leads to higher efficiency and lower noise in resonant converters, allowing more energy to be stored and re-used, rather than dissipated as heat, cycle by cycle. WORKING PARTNER ST’s STNRGxxxA: page 23 With these new devices, designers can create switching power-conversion circuits which are lighter and more compact, while more easily meeting increasingly stringent energy-efficiency targets. The new 600V MDmesh M2 EP devices combine ST’s proven strip layout with a new improved vertical structure and an optimised diffusion process to produce performance close to that of the ideal switch: they combine very low on-resistance and the lowest known turn-off switching losses. The MDmesh M2 EP MOSFETs are tailored for very high-frequency converters switching at higher than 150kHz. • • • • • • • • Vishay Intertechnology has introduced a new series of ENYCAP™ hybrid energystorage capacitors with low 2.5mm profiles which feature industry-high energy density of 13Ws/g. The Vishay BCcomponents 196 HVC ENyCAP series is available in versions with up to six cells and capacitance values from 4F to 90F. Stacked through-hole, surface-mount flat and layflat configurations feature pins, tabs, and connectors. Voltage ratings start at 1.4V for a single-cell configuration, and also include 2.8V, 4.2V, 5.6V, 7.0V and 8.4V versions (with multiple cells). Its unique technology, which requires no cell balancing, provides soft charging characteristics. 24 LIGHTING The low leakage current after 24 hours is in a range from 0.03mA to 0.5mA. For technical evaluation, Vishay provides a complete development kit. This demonstrates a complete 20V/1A buck DC-DC and back-up regulator with integrated ENyCAP charger, charge-current monitor, integrated timer and deep-discharge load-switch protection. The devices offer a useful life of 1,000 hours at 85°C. MEDICAL AUTOMOTIVE SECURITY Board with multiple connection options supports latest Atmel SAM x70 MCUs The Atmel® | SMART™ SAM E70 Xplained evaluation kit is ideal for evaluating and prototyping with the Atmel SAM S70 and SAM E70 microcontrollers, which are based on the ARM® Cortex®-M7 processor core. Servers Laptops Telecoms equipment Consumer devices FEATURES Extremely low gate charge Excellent output-capacitance profile 100% avalanche-tested Zener-protected ENERGY INDUSTRIAL For samples or pricing e-mail [email protected] LIGHTING MEDICAL AUTOMOTIVE SECURITY • Back-up power for data-storage • • • • • • applications Power-failure and write-cache protection for hard disk drives Power sources for real-time clocks Burst-power support for flash lights and wireless transmitters Back-up power for industrial PCs and industrial control systems Storage device for energy-harvesting systems FEATURES Non-hazardous electrolyte Maintenance-free, no service necessary 160145: For samples or pricing e-mail [email protected] FREE BOARDS Orderable Part Number: MAL219699001E3 Apply now at my-boardclub.com Fast-track board request code: FTM61A ENyCAP capacitors: no cell balancing required EMAIL [email protected] FOR SAMPLES AND DATASHEETS hardware support for Audio Video Bridging (AVB). Analogue features include dual 2Msamples/s 12-bit ADCs with an analogue front end offering offset and gain-error correction, and a 1Msample/s 12-bit DAC. The evaluation board’s connectivity options include a 4-bit SD card connector, a Micro-AB USB device connector and a Micro-AB USB debug interface. The board also contains various headers for extension boards, which may be purchased individually. The evaluation board includes an ATSAME70Q21 MCU, which is housed in a 144-lead LQFP package, an AT24MAC402 EEPROM and a 16Mbit IS42S16100E SDRAM memory IC. The ATSAME70Q21 with a floating point unit operates at up to 300MHz and features 2Mbytes of Flash memory. It offers various networking and connectivity peripherals, including a CAN-FD interface and one 10/100Mbits/s Ethernet MAC, with specific ENERGY • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Consumer devices Industrial control equipment PC peripherals FEATURES • Camera extension headers • 10/100 Ethernet PHy • On-board power regulation via 3.3V LDO • One Reset and one unassigned push • button Green user LED 160146: For more information e-mail [email protected] FREE BOARDS Orderable Part Number: ATSAME70-XPLD Apply now at my-boardclub.com Fast-track board request code: FTM61A CONSUMER TELECOMMS APPLICATIONS • MONTH Europe’s electronics industry thrives on the application of innovation and creativity, and an essential innovator’s tool in design projects is the development board. The Board Club website is a Future Electronics resource for users of development boards. Here, and only here, Board Club members can gain access to exclusive free development boards and development board offers. If you would like to register for membership, please visit: www.my-boardclub.com/register.php CONSUMER TELECOMMS APPLICATIONS 160144: Hybrid energy-storage capacitors combine high density and low profile VISHAy INDUSTRIAL THE Future Electronics’ Board Club: supporting innovative electronics design ATMEL ENERGY OF New evaluation boards for 60V synchronous step-down PWM controller INTERSIL The ISL8117EVAL1Z and ISL8117EVAL2Z development boards enable designers to evaluate the performance of the ISL8117, a 60V synchronous buck controller from Intersil. The ISL8117 offers external soft-start and independent enable functions, and integrates various circuit-protection features. Its currentmode control architecture and internal compensation network keep peripheral component count to a minimum. The device’s programmable switching frequency, which ranges from 200kHz to 2MHz, gives the designer the flexibility to optimise the balance between inductor size, power consumption and noise. Both the ISL8117EVAL1Z and ISL8117EVAL2Z evaluation boards are designed for high-current applications, and accommodate a wide inputvoltage range of 4.5V to 60V, in the case of the ISL8117EVAL1Z, and 18V to 60V for the ISL8117EVAL2Z. The current rating of the ISL8117EVAL2Z is limited by the FETs and inductor selected. The ISL8117 gate driver is capable of delivering up to 20A for the buck output as long as the proper FETs and inductor are provided. ENERGY • • • • • INDUSTRIAL LIGHTING MEDICAL AUTOMOTIVE SECURITY CONSUMER TELECOMMS APPLICATIONS Factory automation Security equipment Servers and data centres Switches and routers LED panels FEATURES • High light-load efficiency • Supports pre-bias output with soft-start • External frequency synchronisation • Power Good indicator • Back-biased from output to improve efficiency 160147: For more information e-mail [email protected] FREE BOARDS Orderable Part Numbers: ISL8117EVAL1Z and ISL8117EVAL2Z Apply now at my-boardclub.com Fast-track board request code: FTM61A ISL8117 eval boards: accept input voltages up to 60V To apply for these free boards go to: www.my-boardclub.com/ftm Terms and conditions apply. Visit www.my-boardclub.com/about_us for details 25 TECHNICAL TECHNICAL VIEW VIEW How to reduce the total cost of a power circuit with the use of SiC components By Erich Niklas Regional Sales Manager (Central Europe), Future Power Solutions READ THIS ARTICLE TO FIND OUT ABOUT Silicon Carbide (SiC), a wide bandgap material with markedly superior characteristics to silicon in high-voltage circuits, has struggled to gain widespread market acceptance. In some ways, this is surprising: SiC components – diodes and MOSFETs – are ideal for high-voltage applications in which energy efficiency is a critical parameter. For example, in solar inverters switching losses may be reduced by more than 30% through the use of SiC MOSFETs. Solar inverters with both SiC MOSFETs and diodes have been shown to be capable of achieving overall system efficiency of greater than 99%. Similar efficiency benefits can be achieved in other applications that require high blocking voltages in combination with fast, efficient switching: industrial motor drives, DC power systems in data centres, power factor correction circuits, and high-frequency DC-DC converters in industrial, computing and communications power systems. Benefitting from low switching losses, SiC MOSFETs and diodes can enable operation at switching frequencies up to four times higher than those using conventional silicon IGBTs. So why are SiC components not in widespread use in these applications? The answer is simple: component cost. An expensive manufacturing process means that the cost of a SiC MOSFET is far higher than that of a comparable silicon component. Simply replacing a silicon MOSFET or IGBT in a conventional power circuit with a SiC MOSFET normally makes little financial sense. But this is the wrong way to approach power-system design with SiC components. In fact, the proper use of SiC components can result in lower total system costs, despite the relatively high cost of the SiC components. But if design engineers are to realise cost savings from the use of SiC technology, they must thoroughly review and modify their existing circuits, and possibly even abandon an existing design entirely and start afresh. This article shows why. The cost contributors in a high-voltage power circuit The reason the power-system designer should not focus on a simple cost comparison of silicon and SiC components is that these components make up only a small proportion of the total system cost. In fact, the main cost contributors to a high-voltage circuit are: • Power semiconductors • Heat-sink • Transformers • Inductors • Capacitors • PCB In addition, in some end-product types there might be noticeable costs associated with transport or handling of the end-product. In these cases, the weight and size of the power circuit can have a marked impact on the manufacturer’s costs. When a circuit is designed from the start with the intention of using SiC MOSFETs and diodes, savings can be made in every one of the cost contributors listed above. As a result, design teams that have designed new power circuits to take full advantage of SiC technology Fig. 1: Kollmorgen’s SiC inverter prototype has no need for an expensive liquid cooling mechanism (Source: Kollmorgen) 26 • Why the use of expensive SiC power components can result in lower system costs • Examples of design implementations which have realised performance and cost improvements by replacing silicon IGBTs with SiC MOSFETs • The prospects for wider adoption of SiC power components as their prices fall are gaining a distinct competitive edge. For example, motor-system manufacturer Kollmorgen (www.kollmorgen.com) has developed a prototype of a new SiC-based inverter, as shown in Figure 1, for use in heavy-duty Hybrid Electric Vehicles (HEVs) such as city buses. Specified for operation at 750V DC and 400Arms, the SiC version of the inverter offers the following advantages over the equivalent product that uses silicon IGBTs: • 1% superior system efficiency, the equivalent in a typical city bus to an annual reduction in fuel consumption of between 600 litres and 1,000 litres of diesel fuel • A much cheaper thermal design using air cooling rather than water cooling • Higher-frequency switching, enabling the use of smaller passive components According to Lux Research (www.luxresearchinc.com), the savings in fully Electric Vehicles (EVs) look equally promising. Attempts to extend the performance of silicon devices in high-voltage applications are hitting the physical limits of the material’s characteristics. In an August 2014 paper, the research company found that the use of Wide Bandgap (WBG) materials such as SiC offers economic benefits because of the large batteries in EVs, as shown in Figure 2. ‘Efficient power electronics is key to a smaller battery size, which in turn has a positive cascading impact on wiring, Fig. 2: The dramatic power efficiency gains offered by SiC thermal management, devices will help to slash the cost of electric and hybrid packaging and weight of electric vehicles. (Source: Lux Research) electric vehicles,’ said Pallavi Madakasira, an analyst at Lux Research and the lead author of the report titled Silicon vs WBG: Demystifying the Prospects of GaN and SiC in the Electrified Vehicle Market. On the Tesla Model S for example, a 20% reduction in power use can make the battery system $6,000 cheaper – some 8% of the vehicle’s total cost. According to Lux Research, a power saving of just 2% makes the use of SiC diodes essential in EVs, on the assumption that battery costs fall below $250/kWh. For plug-in HEVs, the threshold for the introduction of SiC components is a 5% power saving. To illustrate the way that SiC components enable cost savings across the whole of a power circuit, let us study an example, an application that has been developed by a Fig. 3: Architecture of the STMicroelectronics 5kW boost-converter circuit (Source: STMicroelectronics) EMAIL [email protected] FOR SAMPLES AND DATASHEETS research team at STMicroelectronics. The prototype developed by ST is a 5kW boost converter, a functional block in a solar inverter, as shown in Figure 3. The prototype uses the following SiC components: • The SCT30N120 is a 1,200V SiC N-channel power MOSFET. It is rated for operation across a junction temperature range of -55°C to 200°C. On-resistance is rated at a typical 80mΩ. • Two STPSC6H12 1,200V SiC Schottky diodes functioning as a rectifier. The system is designed to boost a 400-600V DC input to 800V DC in continuous-current mode, supporting an output power of 5kW. The SiC MOSFET’s maximum junctiontemperature rating is some 25°C higher than that of a comparable silicon IGBT, which means that a smaller heat-sink can be used, as shown in Figure 4. The boost inductor is rated for a maximum 25A current, with low parasitic capacitance and a 25A saturation current. Fig. 4: A SiC MOSFET requires a smaller STMicroelectronics evaluated heat-sink than the equivalent Si IGBT comparable systems at switching (Source: STMicroelectronics) frequencies of 25kHz (the limit of a silicon IGBT’s performance in this application) and 100kHz (with a SiC MOSFET), to examine the trade-off between cost and performance. Increasing the switching frequency allows for the use of a smaller inductor and/or a smaller output capacitor. Technically, given that the maximum current ripple occurs at Vin=Vout/2, the higher the switching frequency the lower the inductance required, according to the formula: Figure 5 shows the reduction in the size and weight of the inductor achieved by operating at the high 100kHz frequency supported by the fast SiC components. Fig. 5: Size and weight comparison of inductor required when switching at 25kHz and 100kHz (Source: STMicroelectronics) A summary of the superior performance achieved by the SiC-based design is shown in Figure 6: with a SiC MOSFET, the system switches four times faster and offers higher efficiency, and uses smaller and lighter magnetics and heat-sink. Even more interesting, Ferrite Core Ferrite Core Heat-sink ƞ% @ Inductor Inductor Parameters Figure 7’s cost Rth (°C/W) 5kW Volume (L) Weight (kg) comparison SiC MOSFET shows that, 98.17 0.78 1.35 0.65 @ 100kHz even though IGBT @ 25kHz 98.13 1.45 3.4 0.53 the SiC Fig. 6: Comparison of performance and component requirements of SiC and MOSFET is IGBT-based designs (Source: STMicroelectronics) nine times more expensive than a silicon IGBT, the total system cost is lower in a design that takes full advantage of the SiC MOSFET’s superior characteristics. This is because the inductor, capacitor and heat-sink are expensive components. Moreover, the benefits of the reduction in weight and size provided in a design based on SiC components come in Inductor 58% 45% addition to the bill-ofCapacitor 15% 9% materials cost savings. Heatsink Another example of 17% 8% IGBT/SiC MOSFET the benefits that SiC 4% 32% components will bring SiC Diode 6% 6% to the fast growing EV Efficiency 98.6% 99.1% market was presented Normalised Total 100% 95% by car manufacturer Fig. 7: SiC MOSFET v Si IGBT cost comparison for a 5kW converter design, showing normalised percentage of BoM cost Toyota at the contributed by each component type (Source: STMicroelectronics) Automotive Engineering Exposition (May 2014, Japan). Toyota estimates that 20% of total electrical power losses in HEVs are attributable to power semiconductors. Improving the efficiency of the power semiconductors directly reduces fuel consumption. Toyota has set a goal of achieving a 10% improvement in HEV fuel efficiency: SiC MOSFETs supplied by Microsemi are now playing a role in its strategy for achieving this goal. Results from development work carried out by Toyota show that power losses when using SiC MOSFETs are around 10% of the power loss suffered by Si IGBTs. In addition, the switching frequency can be increased by a factor of ten, which enables a reduction in the size of the power control unit of around 80%. There is a commercial as well as an engineering benefit to the use of SiC MOSFETs in HEV power supplies. Toyota presented a cost comparison for a three-phase 225kW inverter for an electric vehicle using a 350V battery. Toyota’s current solution uses 84 Si IGBTs. The goal was to replace these with SiC MOSFETs in order to improve system performance at a total cost no higher than that of the current design. The design uses 60 SiC MOSFETs supplied by Microsemi, rated for a maximum voltage of 700V and with typical on-resistance of 40mΩ. It reduces the cost of the battery by 6%, and the magnetics by almost 50%, while the passives and other components have almost the same cost as the IGBT solution. Although the cost of the semiconductors is three times higher than that of the IGBT design, the total system cost is 5% lower. And, as Figure 8 shows, the SiC MOSFET system has a particularly marked efficiency advantage over the IGBT system at low loads. 4kW Boost Converter Vin= 600V, Vout = 800V IGBT + SiC MOSFET + SiC Diode SiC Diode fsw = 25kHz fsw = 75kHz A fast-changing market The examples Fig. 8: Efficiency comparison in HEV inverter, SiC MOSFET vs Si IGBT described above suggest that the cost/performance battle between SiC MOSFETs and IGBTs is finely balanced today. As the months go by, however, the balance will continue to tip further and further in the SiC components’ favour, because of expected steep falls in the price of SiC MOSFETs. This price drop is due to increased competition among wafer suppliers and the transition to a 6” wafer fabrication process. As the basic price of SiC components falls, the benefits to be gained from designing systems around them become even more attractive. For manufacturers of solar inverters, as well as many other types of highpower equipment, a tipping point might now have been reached, at which silicon carbide becomes the favoured material for switching components. 160148: For more information e-mail [email protected] VISIT THE ONLINE FTM MAGAZINE AT: WWW.My-FTM.COM 27 160149: For more information e-mail [email protected]