World`s First 2D Multi-Touch Pad with 3D Gesture

Winter2014
2012
Nov/Dec
World’s First
2D Multi-Touch Pad with
3D Gesture Recognition
CONTROL
ROBUST
COMPACT
IoT APPS
SENSORS
Nov/Dec 2014
Contents
SHOWCASE
DESIGN ARTICLES
4 A Touch Above
18 Measuring Heart Rate and
Blood Oxygen Levels for
Portable and Wearable Devices
3DTouchPad is world’s first 2D multi-touch pad with 3D
gesture recognition
NEW PRODUCTS
6 Take Control
8-bit microcontroller family offers closed-loop digital control and
safety monitoring
8 When the Going Gets Tough
5V dsPIC33 “EV” family offers enhanced noise immunity and
robustness for harsh environments
9 Smart Mix
Latest 32-bit microcontrollers enable a wide range of applications
at lower prices
11 Very Precise
New high-speed devices feature industry’s lowest-power 16-bit,
200 Msps stand-alone ADCs
23 Buck-Based LED Drivers
Using the HV9910B
27 Connected Things Are
the Future of Mobile
29 A Complete Solution for
Mesh Networks
31 Printed Multi-Touch Sensor
Solutions for Modern Designs
32 Accelerating Low-Level
Code Implementation in
PIC32 MCU Applications
FEATURES
15 Product Spotlight
16 Gifts Just For You
33 Connect With Us at 2015
International CES
12 Swapping Roles
USB 2.0 four-port controller hub connects smartphones to
automotive infotainment systems
14 Power Up
Get simple analog PWM control and configurable MCU in compact
circuit solution
The Microchip name and logo, the Microchip logo, dsPIC, FlashFlex, KEELOQ, KEELOQ logo, MPLAB, mTouch, PIC, PICmicro, PICSTART, PIC32 logo, rfPIC, SST, SST Logo, SuperFlash and UNI/O are
registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor, MTP, SEEVAL and The Embedded Control Solutions
Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.
Analog-for-the-Digital Age, Application Maestro, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN, ECONOMONITOR, FanSense, HI-TIDE, In Circuit
Serial Programming, ICSP, Mindi, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, Omniscient Code Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE, rfLAB, Select
Mode, SQI, Serial Quad I/O, Total Endurance, TSHARC, UniWinDriver, WiperLock, ZENA and Z-Scale are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. GestIC and ULPP are registered trademarks of Microchip Technology Germany II GmbH & Co. & KG, a subsidiary of Microchip
Technology Inc., in other countries. All other trademarks mentioned herein are property of their respective companies. © 2014, Microchip Technology Incorporated, All Rights Reserved.
2
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3
SHOWCASE
A Touch Above
3DTouchPad is World’s First 2D Multi-Touch Pad with
3D Gesture Recognition
Rich and Well-Documented Development Platform Enables Advanced
Human-Interface Capabilities for Leading-Edge Applications
H
ave
you
ever
used
free-space
3D gesture recognition at a range of up to
gestures to control your PC? Our
10 centimeters. It offers all the features you
new 3DTouchPad (DM160225) is an
would expect from a touchpad, including sup-
innovative PC accessory which works out of
port for precision, multi-finger tracking as well
the box to provide you with a range of options
as multi-finger surface gestures like swipes
for using touch and gestures to
interact with your PC. It is also
As a PC peripheral, the 3DTouchPad
the first development platform
provides out-of-the-box support for all
for the PC/peripheral market
major operating systems.
that features 2D multi-touch and
It provides an
intuitive and easy
way to control the
flow of content.
and scrolling. With the addition of
support for 3D hand gestures, the
3DTouchPad also provides an
intuitive and easy way to control
the flow of content. For example,
3D gestures, enabling you to easily design
you can browse through pictures on your PC
advanced human-interface capabilities into
using just a wave of your hand or control the
your latest products.
volume of your PC’s speakers by circling your
The 3DTouchPad blends our highly responsive
hand using an air wheel gesture.
projected capacitive (PCAP) sensor solutions
As a PC peripheral, the 3DTouchPad supports
technology for
Windows® 7/8, OS X® and other major operating
with our patented GestIC
®
(continued on page 5)
Figure 1 - 3DTouchPad System Diagram
4
systems, with no driver installation required.
The possibilities for this advanced blend
Simply connect the 3DTouchPad to your PC
of human-to-machine interface technol-
using the provided USB cable and it will be
ogies reach beyond the PC market and
automatically detected as a ready-to-use
computer touchpads to include hands-
Human Interface Device (HID). It is fully com-
free sanitary products, home automation,
patible with Windows 8 requirements, allow-
game controllers, remote controls, wearable
ing you to use the two-finger scrolling and
devices, automotive and other applications.
edge swipes that are part of the Windows 8
Using the available features, demonstrations
user experience.
and sample code for the 3DTouchPad, you
2D Touchpad
can unleash your creativity to develop a
SHOWCASE
variety of engaging applications such as:
• Auto wake-on-proximity or gesture
• Media center control
Multi Touch
Pinch/Zoom
Scrolling
3D Free Space Gestures
Mapped to Windows® Events
• Air wheel for volume control
• Flicks for previous/next track
• Games based on 3D positioning
• Virtual joystick
• Content-aware gesture mapping
In addition to its out-of-the-box features,
PC Wake-Up
Joystick
the 3DTouchPad comes with a rich and
well-documented
Software
Development
Kit (SDK) and Application Programming
Interface (API). The SDK gives you access
to the Colibri Gesture Suite, our easy-to-use
Content
Browsing
Volume/
Brightness
library of high-resolution x/y/z hand position
tracking, flick, circle, and touch gestures
used to perform a variety of input commands.
A free Graphical User Interface (GUI) allows
you to access all the data that is generated by
the 3DTouchPad.
If you’re ready to get started, it's easy to add
2D and 3D human-interface capabilities to
your design. The 3DTouchPad costs $99.00
and can be ordered from microchipDIRECT.
Visit the 3DTouchPad page for additional
information including documentation and
downloads for the latest software and firmware releases. Be sure to also watch our
3DTouchPad video to learn more.
5
Take Control
NEW PRODUCT
New 8-bit Microcontroller Family Offers Closed-Loop
Digital Control and Safety Monitoring
Increased Peripheral Integration Provides Advanced Functional
Control with Hardware PID, Phase Angle Measurement and 100 mA
Current Drive
D
eveloped to take our 8-bit PIC®
(PID), which offers completely core-independent
microcontroller (MCU) performance
calculations and the capability to perform 16-bit
to a new level, Core Independent
math and PID operations. The family also
Peripherals (CIP) can simplify the implementa-
includes the Angular Timer (AngTmr), which
tion of complex control systems and give you
is a hardware module that calculates the rota-
the flexibility you need to create innovative
tional angle in functions, such as motor control,
designs. These peripherals are designed to
TRIAC control, or Capacitive Discharge Igni-
reduce system complexity by eliminating the
tion (CDI) systems. Regardless of speed, the
offers an expanded selection of Core
need for additional code and external com-
AngTmr allows recurring interrupts at a specific
Independent Peripherals.
ponents. Hardware-based peripherals offload
rotational or sinusoidal angle without using the
The PIC16(L)F161X family of devices
timing-critical and core-intensive
core’s computation. The CIPs can
This broad mix
functions from the CPU, allowing
be configured to perform a host of
enables a wide
it to focus on other critical tasks variety of functions. given functions that increase exewithin the system.
cution speeds and decrease softAs the latest additions to our 8-bit product
portfolio, the peripheral-rich PIC16(L)F161X
family of devices offers an expanded selection
of Core Independent Peripherals to give you
ware requirements. Offloading these functions
frees up the CPU do other tasks, consumes
less program memory and reduces the MCU's
overall power consumption.
even more control over your design. This broad
In addition to the Math ACC and AngTmr, the
mix enables a wide variety of functions includ-
PIC16(L)F161X features several other periph-
ing motor control and safety monitoring so that
erals designed to ease implementation and
you can create functions for closed-loop control
add flexibility of various functions. The 24-bit
with little-to-no interaction with the core. These
Signal Measurement Timer (SMT) performs
capabilities allow you to create customizable
high-resolution measurements of digital sig-
functions specific to your application while
nals—in hardware—resulting in more precise
minimizing your code development.
and accurate measurements. This is ideal for
These new devices feature a Math Accelerator
(Math ACC) with Proportional Integral Derivative
speed control, range finding and RPM indicators. The family also includes the Zero Cross
Detect (ZCD) module, which can monitor AC
(continued on page 7)
6
line voltage, and indicate zero crossing
these features allow you to enable
activity. This simplifies the development of
safety and monitoring functions in your
TRIAC control applications, greatly reduc-
applications
ing both CPU demand and Bill of Materials
involvement of the CPU. The family
(BOM) cost. In combination with the new
also offers low-power XLP technology.
High-Current I/Os (100 mA) and the proven
Devices are available in 8-, 14- and 20-pin
Configurable Logic Cell (CLC) along with
small-form-factor package options.
with
NEW PRODUCT
minimum-to-zero
I2C™, SPI and EUSART for communications,
this integration helps speed design, eases
implementation and adds flexibility.
This family also supports the implementation
of safety standards such as Class B and
UL 1998 or fail-safe operations by combining the Windowed Watchdog Timer (WWDT)
which monitors proper software operation
within predefined limits, improving reliability
and Cyclic Redundancy Check with Memory
Scan (CRC/SCAN) that detects and scans
memory for corrupted data. Along with the
Hardware Limit Timers (HLT), which detect
hardware fault conditions (stall, stop, etc.),
Development Support
The PIC16(L)F161X family is supported by
our standard suite of development tools,
including the PICkit™ 3 In-Circuit Debugger
(PG164130) and MPLAB® ICD 3 In-Circuit
Debugger (DV164035). The MPLAB Code
Configurator, which is a plug-in for the free
MPLAB X Integrated Development Environment (IDE), provides a graphical method
to configure 8-bit systems and peripheral
features and gets you from concept to prototype in minutes by automatically generating efficient and easily modified C code for
Contact your local Microchip Sales Office
for information on pricing and the availability
of samples and production quantities for
the various devices in the PIC16(L)F161X
family. You can purchase these devices
from Microchip’s worldwide distribution
network or from microchipDIRECT.
your application.
7
When the Going
Gets Tough
NEW PRODUCT
5V dsPIC33 “EV” Family Offers Enhanced Noise Immunity
and Robustness for Harsh Environments
Featuring Advanced Motor Control, CAN, SENT and Touch Peripherals
for Automotive, Appliance and Industrial Applications
M
any designers of automotive and
provide plenty of performance to execute smart
appliance applications prefer to
sensor filter algorithms and integrate CAN com-
use 5V devices because they offer
munication software. The higher-voltage opera-
increased robustness in high-noise environ-
tion enables more dynamic range and support
ments as well as easy connection to precision
for larger screen sizes in automotive touch user
sensors. Offering the performance of a DSP
interfaces. These devices offer up to 150°C
with the simplicity of an MCU, the newest addi-
operation with AEC-Q100 Grade 0 qualification
tions to our family of 16-bit dsPIC33 Digital
to enable robust automotive applications that are
performance with DSP acceleration for
Signal Controllers (DSCs) feature 5V operation
ideal for under-hood use. With their advanced
high-speed control algorithm execution.
for improved noise immunity and robustness.
peripheral integration, the dsPIC33EV DSCs
They are the ideal choice for devices which
support CAN, LIN and SENT for automo-
need to operate in harsh environments.
tive communications. They also provide 70
The dsPIC33EV devices provide 70 MIPS
Devices in the dsPIC33EV family are the first
dsPIC
®
DSCs with Error Correcting Code
(ECC) Flash for increased reliability and safety.
For safety-critical applications, the dsPIC33EV
devices also include
These devices
Cyclic Redundancy
offer up to
150°C operation. Check (CRC), Deadman Timer (DMT),
and Windowed Watchdog Timer (WWDT)
peripherals, as well as a backup system oscillator and certified Class B software. Other key
features include up to six advanced motor
control PWMs, a 12-bit ADC, and operational amplifiers—an ideal combination for motor
control applications.
The dsPIC33EV devices easily interface to 5V
automotive sensors, offering improved noise
immunity and enhanced reliability. They also
MIPS performance with DSP acceleration for
high-speed control algorithm execution.
Development Support
The dsPIC33EV 5V CAN-LIN Starter Kit
(DM330018) will help you get started with
your design. A new dsPIC33EV256GM106 5V
Motor Control Plug-In Module (MA330036) is
available to plug into the Low-Voltage Motor
Control Development Bundle (DV330100) for
motor control applications.
The dsPIC33EV family offers 28 SOIC, 28 QFN,
28 SPDIP, 44 TQFP, 44 QFN, 64 TQFP and
64 QFN packages, with Flash memory ranging
from 64KB to 256KB, including options with
and without CAN. Devices can be ordered from
Microchip’s worldwide distribution network
or from microchipDIRECT.
8
NEW PRODUCT
Smart Mix
Latest 32-bit Microcontrollers Enable a Wide Range
of Applications at Lower Prices
PIC32MX1/2/5 Series Offers Feature-Rich Peripheral Mix and
Large, Scalable Memory Options
B
Flexible, easy-to-use CAN2.0B controllers
are integrated into these new MCUs.
lending the key features of the existing
capacitive touch sensing hardware for graphics
PIC32MX1/2 and PIC32MX5 families
and touch-sensing interfaces; a 10-bit, 1 Msps,
of 32-bit microcontrollers (MCUs), the
48-channel Analog-to-Digital Converter (ADC);
latest devices in the PIC32MX1/2/5 series deliv-
as well as a full-speed USB 2.0 Device/Host/
er the benefits of a rich peripheral set for a wide
OTG peripheral. To maximize data through-
range of cost-sensitive applications that require
put, each MCU includes four general-purpose
complex code and higher feature integration at
direct memory access controllers (DMAs)
a lower cost.
and two dedicated DMAs on each CAN and
Offering up to 83 DMIPS performance and
USB module.
large, scalable memory options from 64/8 KB
In addition to their rich mix of integrated
to 512/64 KB Flash/RAM, these new MCUs are
hardware peripheral features, these MCUs are
ideal for executing the Bluetooth
audio
software
required
®
for
low-cost Bluetooth audio applications,
including
speakers,
consumer
music-player
docks,
They are ideal
for executing
Bluetooth®
audio software.
supported by the powerful MPLAB®
Harmony software development
framework, which simplifies the
software development process by
integrating the license, resale and
noise-cancelling headsets and clock radios.
support of Microchip and third-party middle-
Flexible, easy-to-use CAN2.0B controllers
ware, drivers, libraries and real time operating
are also integrated into these MCUs, with
systems (RTOS). Readily available software
DeviceNet™ addressing support and program-
packages, such as Bluetooth audio develop-
mable bit rates up to 1 Mbps, along with system
ment suites, Bluetooth Serial Port Profile library,
RAM for storing up to 1024 messages in 32
audio equalizer filter libraries, various Decod-
buffers. This feature allows you to easily employ
ers (including AAC, MP3, WMA and SBC),
CAN communication schemes for industrial and
sample-rate conversion libraries, CAN2.0B
automotive applications.
PLIBs, USB stacks, and graphics libraries can
A wide variety of additional features include
four SPI/I2S™ interfaces for audio processing
and playback, a Parallel Master Port (PMP) and
significantly reduce the development time for
applications such as Bluetooth connectivity,
digital audio, consumer, industrial, medical and
general-purpose embedded control.
(continued on page 10)
9
Development Support
The PIC32MX1/2/5 series of MCUs is also
supported by a variety of tools including the
free MPLAB X Integrated Development
Environment (IDE), as well as the MPLAB
XC32 Compiler, the MPLAB ICD3 In-Circuit
Debugger and the MPLAB REAL ICE™
In-Circuit Emulation System. Several
new development tools are also available.
These include the PIC32MX1/2/5 Starter
Kit (DM320100), PIC32MX570F512L Plugin Module for Explorer 16 Development
Plug-in Module for Bluetooth Audio
Development Kit (MA320017).
NEW PRODUCT
The new PIC32MX1/2/5 MCUs with
the 40 MHz/66 DMIPS speed option are
available now, in 64-pin TQFP and QFN
packages and 100-pin TQFP packages.
The 50 MHz/83 DMIPS speed option for this
series is expected to be available starting in
late January 2015. Devices can be ordered
from Microchip’s worldwide distribution
network or from microchipDIRECT.
Board (MA320015) and PIC32MX270F512L
10
NEW PRODUCT
Very Precise
New High-Speed Devices Feature Industry’s
Lowest-Power 16-bit, 200 Msps Stand-Alone ADCs
MCP37DX1-200 and MCP372X1-200 Families Provide Low Power and
High Integration of Processing Functions in 124-Lead VTLA Packages
L
eaping past existing solutions in the field
time-delay corrections in multi-channel modes.
of high-performance, high-speed A/D
Data is available through the serial DDR LVDS
converters, our new MCP37DX1-200
or parallel CMOS interface and configured
and MCP372X1-200 families are ideal for communication systems, as well as for a number of
These two families feature 12-, 14- and
16-bit pipelined A/D converters.
via SPI.
industrial and other applications
An integrated digital down-converter is included
These two families feature 12-, 14- and 16-bit
communications applications. The 12-bit fami-
pipelined A/D converters with a maximum sam-
lies include an integrated noise-shaping requan-
pling rate of 200 Mega samples per second
tizer, which enables you to lower the noise within
(Msps). The 14- and 16-bit devices feature high
a given band of interest for improved accuracy
accuracy of over 74 dB Signalto-Noise Ratio (SNR) and over
90 dB Spurious Free Dynamic
Range (SFDR), while the 12-bit
devices have 71.3 dB SNR and
in the MCP37DX1-200 family making it ideal for
This enables
high-precision
measurement of
fast input signals.
and performance. These families
are targeted for applications in the
communications markets such as
base stations, test equipment and
IF receivers.
90 dB SFDR. This enables high-precision measurement of fast input signals. These devices
operate at very low power consumption of
490 mW at 200 Msps including LVDS digital
I/O. Lower power-saving modes are available
at 80 mW for standby and 33 mW for shutdown.
The MCP37DX1-200 and MCP372X1-200
include a number of digital processing features
that will simplify your system's design and
reduce the cost and power usage. These families also include decimation filters for improved
SNR, individual phase, offset and gain adjustment and a fractional delay recovery for
Development Support
The MCP37DX1-200 and MCP372X1-200
are supported by the MCP37XXX-200 16-bit
VTLA Evaluation Board (ADM00505), the
MCP37XXX-200 12-bit VTLA Evaluation
Board (ADM00619) and the MCP37XXX-200
Data Capture Card (ADM00506).
The MCP37DX1-200 and MCP372X1-200
devices are available now for sampling and
volume production in 124-lead VTLA packages
from Microchip’s worldwide distribution
network or from microchipDIRECT.
11
Swapping Roles
NEW PRODUCT
USB 2.0 Four-Port Controller Hub Connects Smartphones to
Automotive Infotainment Systems
Upstream Port Selectable Between USB 2.0 and HSIC, I/O Bridging
to Multiple Serial Protocols and Advanced Battery Charging Address
Requirements for Lower Power and Flexibility
I
nnovation in automotive infotainment system
The device's HSIC connectivity incorporates
design is being driven by the growing need
Microchip’s Inter-Chip Connectivity™ tech-
for the seamless integration of personal
nology. This enables the USB84604 UCH2—
devices—like
in-vehicle
when connected on a circuit board—to utilize
use. By leveraging the strengths of USB con-
the ubiquitous USB 2.0 protocol, dramatically
nectivity, you can quickly develop innovative,
decreasing power consumption. This power
leading-edge solutions to meet this demand.
reduction is most obvious when actively trans-
Offering a rich feature set, our new automo-
ferring data and has been measured to be 1⁄7
infotainment system designs requiring USB
tive-grade, four-port USB84604 USB2 Control-
of the power consumed by a pair of traditional
port expansion and connectivity.
ler Hub (UCH2) is ideal for your automotive in-
USB 2.0 physical-layer transceivers.
The USB84604 is ideal for automotive
smartphones—for
fotainment system designs requiring USB port
expansion and connectivity to meet the rising
consumer demand for connected vehicles.
The USB84604 UCH2 features
Microchip's FlexConnect technology and an upstream port that
supports both USB 2.0 and High
Speed Interchip (HSIC) connectivity. FlexConnect technology
The four downstream ports of the USB84604 can
attach to an upstream port as either a full-speed
hub or as a full-/high-speed hub. When con-
This power
reduction is
most obvious
when actively
transferring data.
nected to a high-speed host, the
four downstream-facing ports can
operate at Low Speed (1.5 Mbps),
Full Speed (12 Mbps) or High
Speed (480 Mbps). Additionally, the USB84604’s integrated
allows for easy port reversals or “role swap-
battery-charger-detection circuitry supports both
ping.” The USB84604’s downstream port 1 is
downstream battery detection and charging,
able to swap with the upstream host port, thus
providing the ability to replace external bat-
transferring the host capability to the product
tery chargers with advanced battery-charging
connected to the UCH2, such as smartphones
modes such as USB-IF Battery Charging
and tablets. This unique feature allows for the
(BC1.2) and Apple® device charging.
smartphone ecosystem of software and applications to be connected to the automobile's
infotainment system.
To ensure optimized signal strengths and
robust operation in the harsh Electromagnetic
(continued on page 13)
12
Interference (EMI) environments typical
UART and general-purpose I/O. This
of automotive applications, Microchip’s
enhanced functionality allows you to
VariSense™ and PHYBoost technologies
use the hub controller as a USB slave
have also been integrated into this UCH2.
controller. For example, if an authenti-
Functionality and configurations for the
USB84604 can be loaded from external Flash.
Its on-chip, One-Time-Programmable (OTP)
memory can be used to load permanent
configurations, and its System Management
Bus (SMBus) slave interface can be used
to customize the functionality. This interface
enables control of the digital and USB lines
for internal testing, configuration of the hub to
function with the desired options when enumerating, and the loading of custom firmware
to fully unlock the USB84604's features.
The USB84604 also enables applications
to seamlessly communicate via multiple
protocols and methods, such as I C™, SPI,
2
NEW PRODUCT
cation chip needs to be updated in the infotainment system design, this function could
be easily moved from the HMI to the breakout
box, minimizing requalification.
Development Support
The USB84604 UCH2 is the latest device to
be supported by our free ProTouch configuration software tool. ProTouch software makes
it easy to generate configuration settings and
program the UCH2’s internal OTP memory,
or any external SPI Flash. The USB4604
Evaluation Board (EVB-USB4604) enables
FlexConnect applications and allows access
to the UCH2’s digital pins used in I2C, GPIO
and UART bridging. This development tool
also contains on-board SPI Flash to allow
different revisions of the firmware to be
evaluated on the same PCB.
The four-port USB84604 UCH2 is available
now for sampling and volume production
from Microchip’s worldwide distribution
network or from microchipDIRECT.
13
NEW PRODUCT
Power Up
MCP19118 and MCP19119 Provide Simple Analog PWM
Control and Configurable MCU in Compact Circuit Solution
Industry’s First PMBus™ Compatible Controllers With Up to
40V Operation
W
hile the popularity of digitally
power delivery, point-of-load and automotive
controlled power supplies is growing
power supplies.
rapidly due to their configurability
for a variety of operating conditions and topologies, power system designers also face an
increasing need to be able to report telemetry
and conduct two-way communication—typically
With the integration of a supervisory MCU,
for monitoring and fault reporting—via standard
the MCP19118/9 devices can help you
communication interfaces such as PMBus.
create programmable power supplies.
Also, the recently released USB Power Delivery
and the USB type C connector charging specifications include variable charging
voltages, which allow for rapid
device charging but add potentially
difficult hardware requirements.
With the integration of a supervisory MCU, the
MCP19118/9 devices can help you create programmable power supplies. Key system settings can be adjusted on the fly during operation
by issuing write commands to the registers in
the device. One design can then be reused for
additional applications, using firmware updates
to change the configuration, which minimizes
design, production and inventory
The MCP19118/9
provide a very
compact circuit
solution.
Addressing these challenges, the latest devices
in our portfolio of Digitally Enhanced Power
Analog (DEPA) controllers—the MCP19118
and MCP19119—provide simple, yet effective,
analog PWM control for DC-DC synchronous
buck converters up to 40V, with the configurability of an integrated 8-bit PIC® microcontroller
(MCU). They are the industry’s first devices to
combine 40V operation and PMBus communication interfaces. These features enable quick
power-conversion circuit development with an
analog control loop that is programmable in the
MCU core’s firmware. This integration and flexibility is ideal for power-conversion applications,
such as battery-charging, LED-driving, USB
requirements across multiple platforms. The MCU core can also be
used to perform a variety of other
tasks within the application.
With integrated linear regulators, PWM
generators, ADCs, MOSFET drivers, analog
error amplifiers and control-loop compensation,
the MCP19118/9 devices provide a very compact circuit solution. Properly implemented, this
system is capable of high conversion efficiency
and excellent transient response for reduced
system power losses, smaller heatsinks and
longer battery life in portable applications.
The MCP19118 and MCP19119 are available
for sampling and volume production from
Microchip’s worldwide distribution network
or from microchipDIRECT.
14
PRODUCT SPOTLIGHT
New Flash Memory Solution for Portable Battery-Powered
Embedded Designs
Manufactured with Microchip’s high-performance SuperFlash®
Technology, the SST26WF016B 1.8V Serial Quad I/O™ (SQI™)
SuperFlash Memory device offers 16 Mbit of memory. It provides
the fastest erase times of any competing device, completing
sector and block erase commands in just 18 ms and a full chip
erase operation in 35 ms. Competing devices require in the range
of 10 to 20 seconds to complete a full chip erase operation, making the SST26WF016B approximately 400 times faster. Designed for low power consumption, the SST26WF016B helps maximize
battery life in portable applications. It is an excellent choice for applications such as portable medical
devices, Bluetooth® headsets, GPS, camera modules and hearing aids. More Information.
Energy-Measurement Analog Front Ends Offer High Accuracy
and Integration
Worldwide upgrades to the energy-metering infrastructure are
creating a demand for increased Analog Front End (AFE) accuracy and integration by designers of the latest generation of smart
meters. To meet this demand, the MCP3919 and MCP3912
Energy-Measurement AFEs integrate three and four channels of
24-bit, delta-sigma Analog-to-Digital Conversion (ADC), respectively, with industry-leading accuracy of 93.5 dB SINAD, −107 dB THD and 112 dB SFDR for precise
signal acquisition and higher-performing end products. These are the optimal numbers of channels for single-phase energy meters with neutral monitoring (3-channel); or single-phase, threewire energy meters (4-channel). The high level of integration on these new AFEs also includes a
low-drift voltage reference, programmable gain amplifiers, phase-delay compensation and cyclic
redundancy check (CRC). More Information.
15
DEV TOOL DEALS
Gifts Just For You
I
t’s time again to ring in the savings on a variety of our most popular development tools.
During the microchipDIRECT 2014 End of Year Tools Sale, you can save 25% on starter kits
and boards that will help you add Ethernet and USB connectivity, multimedia capabilities,
Bluetooth® audio and other features to your design. You’ll also find great prices on tools to assist
you in programming and debugging your design. Below are just some highlighted products. You'll
find the full list on the 2014 End of Year Tools Sale page on our website. But act quickly—the
savings end on January 3, 2015.
PICkit™ 3 Starter Kit/Low Pin Count Demo Board
microchipDIRECT Coupon Code: EOY2014DT
Learn how to use the PICkit 3 In-Circuit Debugger/Programmer
using 13 lessons designed to help you get started with programming
PIC® MCUs and dsPIC® DSCs. The low-cost PICkit 3 Starter Kit
(DV164130) also contains a PICkit Low Pin Count Demo Board populated with a PIC16F1829-I/P, as well as a separate sample of the 20-pin
PIC18F14K22-I/P and a micro USB cable. It’s a great deal at 25% off the regular price. Get your
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Mikromedia Board for PIC24
microchipDIRECT Coupon Code: EOY2014DT
A palm-sized unit with amazing multimedia capabilities, the Mikromedia for
PIC24 (TMIK010) is based on the PIC24F256GB110 with USB On-the-Go
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MP3 codec, 8 Mbit serial flash, microSD™ card slot, headphone jack and
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microSD card with full 320 kbps quality. Save 25% during this sale and have
fun developing your next multimedia application.
(continued on page 17)
16
PIC32MZ Embedded Connectivity Starter Kit
microchipDIRECT Coupon Code: EOY2014DT
DEV TOOLS DEALS
Save almost $30 and experience the high performance and
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chipKIT™ Fubarino® Mini Development Board
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Explorer 16 Development Board
microchipDIRECT Coupon Code: EOY2014DT
The Explorer 16 Development Board (DM240001) is our "go to"
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PIC32 Bluetooth Starter Kit
microchipDIRECT Coupon Code: EOY2014DT
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Once you've looked through the full list of products on our End of Year Tools Sale page, head on
over to our December Dev Tools Deals page where you'll find more goodies being offered at up to
50% off their regular prices. Happy holidays!
17
DESIGN ARTICLE
Measuring Heart Rate and
Blood Oxygen Levels for
Portable and Wearable Devices
T
he changes occurring in the medical and fitness fields, along with their associated
electronic devices, can truly be called revolutionary. The demands of today’s healthcare
device markets are many, varied and challenging. Devices that were once primarily found
in hospitals are now used for home-medical applications, as well as for fitness monitoring. For
example, the capability to measure heart rate and blood oxygen levels is showing up more often
now in consumer products. These measurements can be taken using pulse oximeters that are
now available as both home-medical devices as well as part of integrated wrist-worn fitness
activity trackers. This article will cover the basics of pulse oximetry for medical and fitness applications. It will also examine a pulse-oximeter design example that demonstrates the measurement
of heart rate and blood oxygen levels.
What is Oximetry?
Oximetry is the measurement of oxygen saturation in blood, and is usually expressed as a
percentage. A pulse oximeter is a non-invasive device that measures the oxygen saturation
of a person’s blood, as well as their heart rate. Pulse oximeters are easily recognized by their
associated clip-type probe, which is generally applied to a patient’s finger. A pulse oximeter can
be a stand-alone device, part of a patient-monitoring system, or integrated into a wearable fitness
tracker. Accordingly, pulse oximeters are used by nurses in hospitals, outpatients at home, fitness
enthusiasts at the gym and even by pilots in unpressurized aircraft.
What is Blood Oxygen Saturation?
Blood oxygen saturation is measured by examining hemoglobin, which is the oxygen-carrying
pigment of red blood cells that gives them their red color and serves to convey oxygen to the tissues. Hemoglobin is found in two forms. The first is called oxidized hemoglobin, which is denoted
as HbO2 (i.e., oxygen-loaded). The second is called reduced-oxygen hemoglobin, which is denoted
as Hb (i.e., oxygen-depleted). So, blood oxygen saturation (SpO2) is the ratio of Oxy-hemoglobin
to Deoxy-hemoglobin. This can also be expressed as:
(continued on page 19)
18
DESIGN ARTICLE
The value of blood oxygen saturation is
high-end wearable fitness devices utilize the
expressed as a percentage. A normal
reflectance-pulse-oximetry method.
reading is typically 97% or higher.
How Does a Pulse Oximeter Measure
Blood Oxygen Saturation (SpO2)?
How Does a Pulse Oximeter Measure
Pulse Rate?
When your heart beats, it pumps blood through
One of the really interesting things about
your body. During each heart beat, the blood
hemoglobin is how it reflects and absorbs light.
gets squeezed into capillaries, whose volume
For example, Hb absorbs more (and reflects
increases very slightly. Between heart beats,
less) visible red light. HbO2 absorbs more (and
the volume decreases. This change in volume
reflects less) infrared light. Since blood oxygen
affects the amount of light, such as the amount
saturation can be determined by comparing the
of red or infrared light, that will transmit through
values of Hb and HbO2, one method for doing
the tissue. Although this fluctuation is very
this is shining both a red LED and an infrared
small, it can be measured by a pulse oximeter
LED through a body part—such as a finger
using the same type of setup that is employed
or wrist—and then comparing their relative
to measure blood oxygen saturation.
intensities. There are two common methods of
doing this: (1) measuring the light transmitted
through tissue is called transmissive oximetry,
and (2) measuring the light reflected by tissue
is called reflectance oximetry (See Figure 1).
One example of transmissive pulse oximetry
is found in hospitals. Generally, most hospital patient-monitoring systems have an
integrated
transmissive
pulse
oximeter.
On the other hand, many of the newer,
Detailed Theory of Operation
Typical pulse oximeters monitor the oxygen
saturation (SpO2) of a human’s blood, based on
the red light (using a 600-750 nm wavelength)
and infrared light (using a 850-1000 nm wavelength) absorption characteristics of oxygenated hemoglobin (HbO2) and deoxygenated
hemoglobin (Hb). This type of pulse oximeter
flashes the red and infrared lights alternately
(continued on page 20)
Figure 1: Two Oximetry Methods
19
DESIGN ARTICLE
through a body part, such as a finger, to a
photodiode sensor.
The photodiode is normally utilized to receive
the non-absorbed light from each LED. This
signal is then inverted using an inverting
operational amplifier, or op amp. The resulting
The SpO2 can be determined using the ratio
value and a look-up table that is made up of
empirical formulas. The pulse rate can be
calculated based on the pulse oximeter’s
Analog-to-Digital Converter (ADC) sample
number and sampling rate.
signal represents the light that has been
A look-up table is an important part of a pulse
absorbed by the finger, as shown in Figure 2.
oximeter. Look-up tables are specific to a par-
The pulse amplitudes (Vpp) of the red and
infrared signals are measured and converted
to Vrms, in order to produce a ratio value, as
given by the equation below:
ticular oximeter design and are usually based
on calibration curves derived from, among
other things, a high number of measurements
from subjects with various SpO2 levels. Figure 3
shows an example of a calibration curve.
(continued on page 21)
Figure 2: Real-Time Red and Infrared (IR) Pulsation Signals, As Captured By an Oscilloscope
Figure 3: Sample Calibration Curve
20
DESIGN ARTICLE
Circuit Design Description
The following example will detail the different
sections of a transmissive pulse-oximeter
design. This design, as shown in Figure 4,
demonstrates the measurement of both the
Controller (DSC), where the percentage of
SpO2 is calculated.
LED Driver Circuit
A dual single-pole, double-throw analog switch,
pulse rate and blood oxygen saturation levels.
driven by two PWM signals from the DSC,
Probe
and off. In order to acquire the proper number
The SpO2 probe used in this example is an
of ADC samples and still have enough time to
off-the-shelf finger clip that integrates one red
process the data before the next LED turns
LED and one IR LED, plus a photodiode. The
on, the LEDs are switched on and off accord-
LEDs are controlled by the LED driver circuit.
ing to the timing diagram in Figure 5. The
The red light and IR light passing through the
LED current/intensity is controlled by a 12-bit
finger are detected by the signal-conditioning
Digital-to-Analog Converter (DAC), which is
circuit, and are then fed into the 12-bit ADC
driven by the DSC.
alternately turns the red and infrared LEDs on
module that is integrated into the Digital Signal
(continued on page 22)
Figure 4: Transmissive Pulse Oximeter System Block Diagram
Figure 5: Timing Diagram
21
DESIGN ARTICLE
Analog Signal-Conditioning Circuit
One ADC sample is taken during each LED’s
The signal-conditioning circuit has two
on-time period, and one ADC sample is taken
stages. The first stage is the transimpedance
during both LEDs’ off-time periods. Due to the
amplifier, and the second stage is the gain am-
challenges of taking light-based measure-
plifier. A high-pass filter is placed between the
ments through organic tissue, the filter design
two stages.
tool was used to implement a 513th-order,
The transimpedance amplifier converts the
few micro amps of current, which are generated by the photodiode, to a few millivolts. The
signal received from this first-stage amplifier
then passes through a high-pass filter, which is
designed to reduce background-light interference. The output of the high-pass filter is then
sent to a second-stage amplifier with a gain of
22 and a DC offset voltage of 220 mV. The
values for the amplifier’s gain and DC offset
are set to properly place the output signal level
of the gain amplifier into the MCU’s ADC range.
digital-FIR, bandpass filter, which enabled us
to filter the ADC data. This filtered data was
then used to calculate the pulse amplitude, as
shown in Figure 6. The specifications of our
FIR bandpass filter are:
• Sampling Frequency (Hz): 500
• Passband Ripple (-dB): 0.1
• Passband Frequency (Hz): 1 & 5
• Stopband Ripple (-dB): 50
• Stopband Frequency (Hz): 0.05 & 25
• Filter Length: 513
• FIR Window : Kaiser
The home-medical and fitness markets are
growing at a rapid pace. The demand for
Digital Filter Design
The output of the analog signal-conditioning
circuit is connected to the DSC’s integrated
12-bit ADC module. For this example, we used
a dsPIC33FJ128GP802 dsPIC DSC. This
®
enabled us to take advantage of not only its
integrated DSP capabilities, but also of our
Digital Filter Design Tool.
devices that can measure heart rate and blood
oxygen levels will only increase over the next
few years. Pulse-oximeter reference designs
can be very helpful in providing medical and fitness device designers with a head start toward
getting their designs into production and out
to market. Visit the Pulse-Oximeter Design
page on our website for more information.
Figure 6: Input and Filtered Data
Graph 1, shown in red, is the input signal to the FIR filter
Graph 2, shown in green, is the output signal from the FIR filter
X-Axis shows the number of ADC samples; Y-Axis shows the ADC code values
22
DESIGN ARTICLE
Buck-Based LED Drivers
Using the HV9910B
F
undamental buck converter topology is an excellent choice for LED drivers in off-line—as
well as low-voltage—applications as it can produce a constant LED current at very high
efficiencies and low cost. A peak-current-controlled buck converter can give reasonable
LED current variation over a wide range of input and LED voltages and needs little effort in feedback control design. Coupled with the fact that these converters can be easily designed to operate
at above 90% efficiency, the buck-based driver becomes an unbeatable solution to drive high
brightness LEDs.
The HV9910B Universal High Brightness LED Driver provides a low-component-count and
low-cost solution to implement a continuous mode buck converter. The HV9910B has two current
sense threshold voltages: an internally set 250 mV and an external voltage at the LD pin. The
actual threshold voltage will be the lower of these two voltages. The low sense voltage allows
the use of low-current sense resistor values. The HV9910B operates down to 8V input, which is
required for automobile applications, and can take a maximum of 450V input, which makes it ideal
for off-line applications. It also has an internal regulator that supplies power to the IC from the input
voltage, eliminating the need for an external low-voltage power supply. It is capable of driving the
external FET directly, without the need for additional driver circuitry. Linear or PWM dimming can
also be easily implemented using the HV9910B.
This article discusses the design of a buck-based LED driver using the HV9910B with the help of
an off-line application example. The same procedure can be used to design LED drivers with any
other lower-voltage AC or DC input; 12V for example. This information also applies to the HV9910
Universal High Brightness LED Driver.
AC Input Voltage Range
Vnom,ac = 120V rms
Expected LED String Voltage
Vo,min = 20V
Vmin,ac = 90V rms
Vmax,ac = 135V rms
Stabilized LED Current Expected Efficiency
Vo,max = 40V
Io,max = 350 mA
η = 0.9
freq = 60 Hz
Table 1: Buck-Based LED Driver Design Specifications
23
DESIGN ARTICLE
Figure 1: Buck-Based LED Driver Circuit Diagram
Step 1: Switching Frequency and
The 1.5 factor in Equation 1—a 50% safety
Resistor (R1)
margin—is more than enough. For this design,
The switching frequency determines the size of
the inductor L1 and size or type of input filter
choose a 400V, 1.0A diode bridge.
capacitor C2. A larger switching frequency will
Placing a thermistor (or resistor) in series with
the switching losses in the circuit. For off-line
inrush charging current to input bulk capacitor
result in a smaller inductor, but will increase
applications, typical switching frequencies
should be in the range of 20 kHz–150 kHz. The
higher the input voltage range (for example,
in Europe 230 Vac), the lower the frequency
should be to avoid extensive capacitive losses
in the converter. For North America's AC line,
an input bridge rectifier will effectively limit the
C1 during the initial start-up of the converter.
However, adding such a passive inrush current
limiter will increase power loss in normal
steady-state operation of the converter. Hence,
a trade-off between the inrush current limit and
the power efficiency should be considered. A
a frequency of fS = 100 kHz is a good compro-
good rule of thumb is that the thermistor should
this is 228 kΩ.
times the steady state current, as given by
Step 2: Choose the Input Diode Bridge (D1)
applied. The required cold resistance is:
mise. The oscillator resistor needed to achieve
limit the inrush current to not more than five
Equation 2, assuming maximum voltage is
and the Thermistor (NTC1)
The voltage rating of the diode bridge will
(Equation 3)
depend on the maximum value of the input
voltage. The current rating will depend on the
maximum
average
current
drawn
by
the converter.
This gives us a 200Ω resistance at 25°C.
Choose a thermistor with a resistance around
200Ω and rms current greater than 0.2A for
(Equation 1)
this application.
Step 3: Choose the Input
Capacitors (C1/C2)
(Equation 2)
One limitation of a fixed switching-frequency
Note: See Equation 4 for a definition of VMIN,DC.
ratio of 0.5. To avoid instability, the LED string
design is the maximum voltage transformation
(continued on page 25)
24
DESIGN ARTICLE
voltage must not exceed one half of the
In this design example, the high-frequency
lowest input voltage. For this example, the
capacitance required is about 250V, 0.47µF.
minimum rectified voltage should be:
(Equation 4)
The hold-up and input filter capacitor required
at the diode bridge output have to be calculated at the minimum AC input voltage. The minimum capacitor value can be calculated as:
Step 4: Choose the Inductor (L1)
The inductor value depends on the switching
ripple current in the LEDs. Assume a ±15%
ripple (a total of 30%) in the LED current.
Note: One could go up to ±30% to reduce the
size of the inductor more than twice. However,
this would result in reduced efficiency and,
possibly, reduced LED lifetime.
(Equation 5)
where freq = 50 Hz (or 60 Hz) is the AC line
Then, the inductor L1 can be computed at the
rectified value of the nominal input voltage as:
frequency. In this example, C1 ≥ 26.45 μF.
Note: Equation 5 yields a conservative
estimate for the least amount of capacitance required. See the Appendix for a
more accurate calculation of the required
capacitor value.
(Equation 8)
In this example, L1 = 2.9 mH.
The peak current rating of the inductor will be:
The voltage rating of the capacitor should be
chosen greater than the peak input voltage
with a 10–12% safety margin.
(Equation 6)
Choose a 250V, 33 μF electrolytic capacitor
(Equation 9)
The rms current through the inductor will be the
same as the average current for the chosen
30% ripple. The right inductor for this application is an off-the-shelf 2.7 mH, 0.54A (peak),
for C1.
0.33A (rms) inductor.
Electrolytic capacitors have a sizable ESR
Step 5: Choose the FET (Q1) and
component, making them unsuitable for
absorbing the high-frequency ripple current
generated by the buck converter. Therefore,
adding a small film capacitor in parallel with the
Diode (D2)
The peak voltage seen by the FET is equal
to the maximum input voltage. Using a 50%
safety rating,
electrolytic capacitor is a good practice to
absorb the high-frequency ripple current. The
required high-frequency capacitance can be
computed as:
(Equation 10)
The maximum rms current through the FET
depends on the maximum duty cycle, which is
50% by design. Hence, the current rating of the
(Equation 7)
FET is:
(Equation 11)
(continued on page 26)
25
DESIGN ARTICLE
Typically a FET with about three times the
current is chosen to minimize the resistive
Step 6: Choose the Sense Resistor (R2)
The sense resistor value is given by:
losses in the switch.
For this application choose a 300V, <1A
(Equation 14)
MOSFET, such as a BSP130 from Phillips. The
actual MOSFET type should be determined
if the internal voltage threshold is being used.
by the transistor’s permitted power dissipation
Otherwise, substitute the voltage at the LD pin
on the printed board. For example, a BSP130
instead of the 0.25V in Equation 14.
SOT-223 package limits the dissipation to less
than a watt at 50°C temperature rise, even if
the MOSFET peak current capability is 1.5A.
For this design, R2 = 0.55Ω. Also calculate the
resistor power dissipation:
A good rule of thumb is to limit the overall
(Equation 15)
MOSFET power dissipation to not more than
3–5% of total output power by selecting the
right transistor. Selecting a larger MOSFET
may not necessarily improve overall efficiency
due to its larger gate charge causing greater
commutation losses. Moreover, the increased
gate drive current will cause higher power loss
in the HV9910 which takes its supply current
from the rectified AC line input directly. Larger
MOSFETs also tend to have larger drainsource capacitances which increase switching
Design for DC/DC Applications
With the exception of the input filter, a similar
design procedure can be applied to DC/DC
applications. An example of such circuit can be
found in HV9910BDB3, a reference design.
Appendix
The more accurate equations for computing
the required capacitance values are:
losses as well.
The peak voltage rating of the diode is the
same as that of the FET. Hence,
(Equation 12)
The average current through the diode is:
For the example in this article, the actual
minimum capacitance required from the above
(Equation 13)
Choose a 300V, 1A ultra-fast diode.
equations is 19 μF (as compared to 26 μF from
Equation 5).
26
DESIGN ARTICLE
Connected Things Are
the Future of Mobile
WillowTree Apps Named Microchip’s First Mobile App
Developer Specialist
O
ur digital and physical worlds continue to
converge, presenting designers of connected embedded products for the Internet of
Things (IoT) market with an array of new challenges.
Designers can turn to Microchip to select from our
variety of wireless solutions, sensors and eXtreme Low Power (XLP) PIC® microcontrollers, but
many also face the task of designing and developing the refined interfaces that users have come
to expect from their mobile devices. Sometimes they do not have the necessary expertise to take
on this task in-house.
Rather than trying to replicate existing interfaces, many designers would rather tap into the
installed infrastructure to create apps for monitoring and control in real time and from any location.
In combination with cloud-based connectivity, mobile apps are a natural way for users to interface
with things such as wearable fitness monitors, security systems, home automation, garage-door
openers and industrial controls. But, that first experience with an app can make or break a product.
Recognizing this need and building on our deep roster
of traditional embedded hardware and software development design partners, we have recently added the
category of App Developer Specialist to our worldclass Design Partner Network. Companies in this category will offer an exclusive focus on web and nativeapp creation to assist you with getting your IoT design
up and running. WillowTree Apps, an award-winning
and experienced iOS, Android™ and mobile web app developer, has been named as our first App
Developer Specialist. Their innovative, best-in-class web and mobile app designers are ready to
help you reduce the risk, complexity and time of app creation by doing the work for you. This will
allow you to focus on the core of your IoT design and expedite your development cycle, while
(continued on page 28)
27
DESIGN ARTICLE
also ensuring an excellent mobile-interface
kit’s cloud-based demo. WillowTree can also
experience for your users.
modify this cloud-demo app to suit a broad
SInce WillowTree Apps wrote the first mobile
range of IoT design requirements.
app for our Wi-Fi® Client Module Develop-
Visit our Internet of Things Design Center to
ment Kit 1 we have first-hand experience
get information on our range of solutions that
with their capabilities. This app is newly avail-
help you successfully connect your embedded
able from the Apple App Store and enables
system to the cloud.
®
SM
you to quickly get up and running with the
28
DESIGN ARTICLE
A Complete Solution for
Mesh Networks
IQRF™ Platform Proves Ecosystem for Developing a Range of
Wireless Applications
D
o you need to add remote wireless control to your
application? The IQRF™ platform supports RF
connectivity intended for use in low-power, low-speed
and low-data-volume wireless applications running in the subGHz industrial, scientific and medical (ISM bands). It is a complete ecosystem that incorporates hardware, software, development support and services, making it extremely easy and
straightforward to develop wireless mesh networks for a wide range of applications including telemetry, smart metering, building automation, lighting and the Internet of Things. The DS-START-03
IQRF Development Set by MICRORISC Ltd., one of our Design Partners, provides the tools you
need to get started with your IQRF-based wireless application.
IQRF Technology Overview
Gateways allow an IQRF network to be easily connected to the rest of the world. USB gateways
support the development, local control and maintenance of a wireless network while TCP/IP gateways—such as Wi-Fi®, Ethernet and GPRS—provide Internet connectivity and are supported
by the free IQRF Cloud server for easy remote monitoring, data logging and control. The free
SDK software package with libraries, drivers and tools makes it easy to add wireless functionality
to a variety of popular devices including PCs, plug computers and Raspberry Pi® and Arduino®
based systems.
An IRQF transceiver module is a tiny, intelligent electronic board that serves as the basic
communication component for the platform. Since the operating system is built into each transceiver, you can focus on your application development rather than the wireless implementation.
Hardware profiles (HWP), which are free and ready-to-use software plug-ins, can be uploaded
to the transceivers to allow you to communicate with peripherals over the wireless mesh network with no programming required. An IQRF transceiver equipped with an HWP is called a Data
Controlled Transceiver (DCTR). DTCRs are very easy to deploy and are interoperable.
(continued on page 30)
29
DESIGN ARTICLE
In
addition
to
supporting
standard
• Fast Response Commands (FRC™)
communication, every transceiver can route
provide the fastest control, management
packets for other nodes to extend the range
and data aggregation in mesh networks
and increase the reliability of the mesh network. Up to 240 hops can be supported in real
time. Dedicated routers are optional in an IQRF
wireless network. Despite its many unique and
patented features and its high level of sophistication, you’ll find that IQRF technology is
exceptionally easy to implement.
Features
• Programming-free development with IQRF
Data Controlled Transceivers reduces costs
and development time
• Robust routing algorithm and automatic
discovery enable reliable wireless mesh
networks
• Advanced network maintenance tools—
bonding, back up, replacements—reduce
maintenance costs
• IQRF IDE for programming, in-circuit
debugging and network management and
maintenance
• RF Programming (RFPGM™) enables
wireless application code to be uploaded
simultaneously to multiple transceivers
• Standard, low-power and extra-low-power
modes operate independently in receiving
and transmitting modes
Getting Started
The DS-START-03 Development Set contains
the following items:
• Three IQRF transceivers
• IQRF programmer and debugger
• Two universal portable development kits for
TR modules
• Micro USB cable
• USB flash drive with software and
documentation
Visit the IQRF Support Page where you'll find
additional information, including step-by-step
guides and instructional videos to help you get
started with your application.
Figure 1: DS-START-03 Contents
Figure 2: DS-START-03 Programming and Uploading Procedure
30
DESIGN ARTICLE
Printed Multi-Touch Sensor
Solutions for Modern Designs
Xymox’s Flexible Printed Sensors Combine with Microchip’s
Low-Power Touch Electronics
F
lexibility, total system power and cost are
critical to adding touch and gestures to product
designs. In the fast-paced consumer market,
designers face the challenge of creating innovative interfaces for products such as wearables and
handheld controls, while in the industrial market they
need robust solutions for use in bar code readers,
thermostats and various other devices.
Microchip has recently partnered with Xymox Technologies to provide a complete, cost-effective
touch and gesture interface solution that is well suited to meet the cost and power design challenges of a wide array of modern applications. Xymox’s printed transparent PEDOT:PSS conductive polymer sensors are made with KODAK Highly Conductive Film (HCF). When combined with
our low-cost, low-power touch electronics, they enable fast, inexpensive development of touch
and gesture enabled devices.
You can leverage the fast turnaround and low manufacturing minimums of Xymox printed sensors
and integrate them with our versatile touch electronics solutions to keep pace with your changing
touch interface requirements. Xymox can design and manufacture a custom projected capacitive
sensor that is a cost-effective alternative to traditional ITO sensors. Xymox printed sensors are
also formable to meet the challenges of curved surfaces being used in today’s modern designs.
To learn more about adding our industry-leading low-power touch electronics and Xymox
printed flexible touch sensors to your new product design, contact your local Microchip
Sales Office.
31
DESIGN ARTICLE
Accelerating Low-Level
Code Implementation in
PIC32 MCU Applications
ThreadX® RTOS Now Supports MPLAB® Harmony Framework
U
sed in a huge number of products with
applications in consumer electronics, medical devices, industrial equipment and home
automation, Express Logic’s ThreadX RTOS is a
priority-based, fully preemptive, deterministic RTOS.
ThreadX provides basic system services such as
preemptive and round-robin scheduling, semaphores, message queues, mutexes, timers, interrupts and memory management. ThreadX also
offers advanced features such as Preemption-Threshold™ Scheduling, Integrated Event and
Downloadable Application Modules.
We are pleased to announce that the ThreadX RTOS has recently been integrated into the
MPLAB Harmony Integrated Software Framework, a set of integrated building blocks that
simplify and accelerate software development for our 32-bit PIC32 microcontrollers. MPLAB
Harmony provides the industry’s most advanced framework of software drivers and middleware
components that are easy to use and configure, and that work together in complete harmony.
With this seamless integration, ThreadX for MPLAB Harmony offers you with a flexible, fully integrated firmware development platform for your most demanding real-time applications. You can
be confident that your RTOS will be able to keep up with system events under the most extreme
run-time conditions.
ThreadX for MPLAB Harmony is a high-quality, easy-to-use software framework that eliminates
the bugs, hassle, and uncertainty of low-level code implementation, while improving performance
and determinism. With its many features, it will help accelerate your time to market and also
significantly reduce your development costs. The royalty-free, limited source version of ThreadX
for MPLAB Harmony—with prices starting at $6,000—is available from microchipDIRECT.com.
It is also available from Express Logic in full source code form, with license prices starting
at $12,500.
32
EVENTS
Connect With Us at
2015 International CES
O
nce again, representatives from the top consumer electronics retailers and the world’s
greatest technology leaders are getting ready to converge in Las Vegas to attend the
annual International CES. Microchip will be there too, with more than 30 demos on
display that span a wide range of product markets. Visit our main exhibit in Booth MP25656, South
Hall 2 Meeting Place at the Las Vegas Convention Center to see our broad portfolio of innovative
solutions in the automotive, computing, connectivity, Internet of Things, touch and input sensing,
and wireless markets. If you'd like more in-depth information while you're at the show, you can use
our Online Demo Request system to schedule an appointment to meet with representatives from
Microchip and to view specific demos from these different applications areas:
Automotive Zone: Learn how our connectivity and HMI solutions contribute to the advancement
of intelligence throughout the vehicle. Let our experts demonstrate our latest technologies to
further enhance mobile connectivity in the car.
Computing Zone: Need computing expertise? Stop by and experience the leading innovation of
Microchip’s products for computing applications.
Embedded Wireless Solutions Zone: Microchip’s wireless solutions are designed to get you to
market fast, so come see us and let’s find the right wireless solution for your project.
Internet of Things (IoT) Zone: Our variety of wireless solutions, sensors and eXtreme Low
Power (XLP) PIC® microcontrollers enable end-to-end solutions that help successfully connect
embedded systems to the cloud and take advantage of all of the benefits of doing so.
Connectivity Zone: Stop by to learn how Microchip can enhance your mobile experience and
seamlessly connect your world with our USB products.
Touch & Input Sensing Zone: Experience our award-winning solutions for 21st century input
sensing—from buttons, sliders, touchpads and touch screens to three-dimensional gesture
sensing. Learn how our 1-2-3D solutions can be used to enable a wide range of applications.
We’re excited to have this opportunity to meet you and demonstrate why we are a leading provider
of microcontroller, mixed-signal, analog and Flash-IP solutions. See you in Las Vegas!
33
eXtreme Low Power MCUs
Extend Battery Life
Low Sleep Currents with
Flexible Wake-up Sources
■ Sleep current down to 9 nA
■ Brown-Out Reset down to 45 nA
■ Real-Time Clock down to 400 nA
Low Dynamic Currents
■ As low as 30 µA/MHz
■ Power-efficient execution
Large Portfolio of XLP MCUs
■ 8–100 pins, 4–128 KB Flash
■ Wide selection of packages,
including chip scale packages
Battery-Friendly Features
■ Enable battery lifetime > 20 years
■ Operate down to 1.8V with self
write and analog functions
■ Low-power supervisors for safe
operation (BOR, WDT)
Flexible Peripheral Set
■ Integrated USB, LCD, RTC and
touch sensing
■ Eliminates costly external
components
microchip.com/xlp
The Microchip name and logo and the Microchip logo are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
All other trademarks are the property of their registered owners. © 2014 Microchip Technology Inc. All rights reserved. 5/14
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