Microchip Technology MCP1643 User Manual

MCP1643 RGB LED Driver

Demonstration Board

User’s Guide

 2016 Microchip Technology Inc. DS50002437A

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ISBN: 978-1-5224-0152-0

EELOQ, KEELOQ logo, Kleer,

32

logo, RightTouch, SpyNIC,

QUALITY MANAGEMENT S

 2016 Microchip Technology Inc. DS50002437A-page 2

Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and de sign centers in California
and India. The Company’s quality system processes and procedures
are for its PIC
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.

®

MCUs and dsPIC® DSCs, KEELOQ

®

code hopping

Object of Declaration: MCP1643 RGB LED Driver Demonstration Board

 2016 Microchip Technology Inc. DS50002437A-page 3

MCP1643 RGB LED Driver Demonstration Board User’s Guide

NOTES:

DS50002437A-page 4  2016 Microchip Technology Inc.

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

Tabl e of Conten ts

Preface ...........................................................................................................................7

Introduction............................................................................................................ 7

Document Layout .................................................................................................. 7

Conventions Used in This Guide ........................................................................... 8

Warranty Registration............................................................................................ 9

Recommended Reading........................................................................................ 9

The Microchip Web Site ........................................................................................ 9

Customer Support ............................................................................................... 10

Revision History .................................................................................................. 10

Chapter 1. Product Overview

1.1 Introduction ................................................................................................... 11

1.2 MCP1643 Device Overview ......................................................................... 11

1.3 MCP1643 Device Key Features ................................................................... 11

1.4 MCP1643 RGB LED Driver Demonstration Board Overview ....................... 12

1.5 MCP1643 RGB LED Driver Demonstration Board Features ........................ 13

1.6 What the MCP1643 RGB LED Driver Demonstration Board Kit Includes .... 13

Chapter 2. Installation and Operation

2.1 Introduction ................................................................................................... 15

2.2 Getting Started ............................................................................................. 16

2.3 Board Testing ............................................................................................... 16

Chapter 3. Flow Charts
Appendix A. Schematics and Layouts

A.1 Introduction .................................................................................................. 21

A.2 Board – Schematic ....................................................................................... 22

A.3 Board – Top Silk .......................................................................................... 23

A.4 Board – Top Silk and Copper ....................................................................... 23

A.5 Board – Top Copper .................................................................................... 23

A.6 Board – Bottom Copper ............................................................................... 23

A.7 Board – Bottom Silk and Copper ................................................................. 23

A.8 Board – Bottom Silk ..................................................................................... 24

Appendix B. Bill of Materials (BOM)...........................................................................25

Worldwide Sales and Service ....................................................................................26

 2016 Microchip Technology Inc. DS50002437A-page 5

MCP1643 RGB LED Driver Demonstration Board User’s Guide

NOTES:

DS50002437A-page 6  2016 Microchip Technology Inc.

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

Preface

NOTICE TO CUSTOMERS

All documentation becomes dated, and this manual is no exception. Microchip tools and
documentation are constantly evolving to meet customer needs, so some actual dialogs
and/or tool description s may differ from th ose in this docume nt. Please refer to our web site
(www.microchip.com) to obtain the latest documentation available.

Documents are identified with a “DS” numb er. This number is located on the bottom of each
page, in front of the page number. The numbering convention for the DS number is
“DSXXXXXXXXA”, where “XXXXXXXX” is the document number and “A” is the revision level
of the document.

For the most up-to-date information on development tools, see the MPLAB
Select the Help menu, and then Topics to open a list of available online help files.

®

IDE online help.

INTRODUCTION

This chapter contains general information that will be useful to know before using the
MCP1643 RGB LED Driver Demonstration Board. Items discussed in this chapter
include:

• Document Layout

• Conventions Used in This Guide

• Recommended Reading

• The Microchip Web Site

• Development Systems Customer Change Notification Service

• Customer Support

• Revision History

DOCUMENT LAYOUT

This document describes how to use the MCP1643 RGB LED Driver Demonstration
Board. The document is organized as follows:

• Chapter 1. “Product Overview” – Important information about the MCP1643

RGB LED Driver Demonstration Board.

• Chapter 2. “Installation and Operation” – Includes instructions on installing and

getting started with the MCP1643 RGB LED Driver Demonstration Board.

• Chapter 3. “Flow Char ts” - Contains flow charts for the MCP1643 RGB LED

Driver Demonstration Board.

• Appendix A. “Schematics ad Layouts” – Shows the schematic and layout

diagrams for the MCP1643 RGB LED Driver Demonstration Board.

• Appendix B. “Bill of Materials (BOM)” – Lists the parts used to build the

MCP1643 RGB LED Driver Demonstration Board board.

 2016 Microchip Technology Inc. DS50002437A-page 7

CONVENTIONS USED IN THIS GUIDE

This manual uses the following documentation conventions:

DOCUMENTATION CONVENTIONS

Description Represents Examples

Arial font:

Italic characters Referenced books MPLAB

Initial caps A window the Output window

Quotes A field name in a window or

Underlined, Italic text with
right angle bracket

Bold characters A dialog button Click OK

N‘Rnnnn A number in verilog format,

Text in angle brackets < > A key on the keyboard Press <Enter>, <F1>

Courier New font:

Plain Courier New Sample source code #define START

Italic Courier New A variable argument file.o, where file can be

Square brackets [ ] Optional arguments mcc18 [options] file

Curly brackets and pipe
character: { | }

Ellipses... Replaces repeated text var_name [,

Preface

®

IDE User’s Guide

Emphasized text ...is the only compiler...

A dialog the Settings dialog
A menu selection select Enable Programmer

“Save project before build”

dialog

A menu path File>Save

A tab Click the Power tab

4‘b0010, 2‘hF1
where N is the total number of
digits, R is the radix and n is a
digit.

Filenames autoexec.bat
File paths c:\mcc18\h
Keywords _asm, _endasm, static
Command-line options -Opa+, -Opa-
Bit values 0, 1
Constants 0xFF, ‘A’

any valid filename

[options]

Choice of mutually exclusive
arguments; an OR selection

Represents code supplied by
user

errorlevel {0|1}

var_name...]

void main (void)

{ ...

}

 2016 Microchip Technology Inc. DS50002437A-page 8

RECOMMENDED READING

This user's guide describes how to use the MCP1643 RGB LED Driver Demonstration
Board. Other useful documents are listed below. The following Microchip documents
are available and recommended as supplemental reference resources:

• MCP1643 Data Sheet – “1 MHz Low Start-up Voltage Synchronous Boost
LED Constant Current Regulator” (DS20005208)

• PIC16F1455 Data Sheet – “USB Port Power Controller with Charger
Emulation” (DS200005346)

THE MICROCHIP WEB SITE

Microchip provides online support via our web site at www.microchip.com. This web
site is used as a means to make files and information easily available to customers.
Accessible by using your favorite Internet browser, the web site contains the following
information:

• Product Support – Data sheets and errata, application notes and sample

programs, design resources, user’s guides and hardware support documents,
latest software releases and archived software

• General Technical Support – Frequently Asked Questions (FAQs), technical

support requests, online discussion groups, Microchip consultant program
member listing

• Business of Microchip – Product selector and ordering guides, latest Microchip

press releases, listing of seminars and events, listings of Microchip sales offices,
distributors and factory representatives.

Preface

DEVELOPMENT SYSTEMS CUSTOMER CHANGE NOTIFICATION SERVICE

Microchip’s customer notification service helps keep customers current on Microchip
products. Subscribers will receive e-mail notification whenever there are changes,
updates, revisions or errata related to a specified product family or development tool of
interest.

To register, access the Microchip web site at www.microchip.com, click on Customer
Change Notification and follow the registration instructions.

The Development Systems product group categories are:

• Compilers – The latest information on Microchip C compilers, assemblers, linkers

and other language tools. These include all MPLAB C compilers; all MPLAB
assemblers (including MPASM™ assembler); all MPLAB linkers (including
MPLINK™ object linker); and all MPLAB librarians (including MPLIB™ object
librarian).

• Emulators – The latest information on Microchip in-circuit emulators.This

includes the MPLAB REAL ICE™ and MPLAB ICE 2000 in-circuit emulators.

• In-Circuit Debuggers – The latest information on the Microchip in-circuit

debuggers. This includes MPLAB ICD 3 in-circuit debuggers and PICkit™ 3
debug express.

• MPLAB

Integrated Development Environment for development systems tools. This list is
focused on the MPLAB IDE, MPLAB IDE Project Manager, MPLAB Editor and
MPLAB SIM simulator, as well as general editing and debugging features.

• Programmers – The latest information on Microchip programmers. These include

production programmers such as MPLAB REAL ICE in-circuit emulator, MPLAB
ICD 3 in-circuit debugger and MPLAB PM3 device programmers. Also included
are nonproduction development programmers such as PICSTART
PICkit 2 and 3.

®

IDE – The latest information on Microchip MPLAB IDE, the Windows

®

Plus and

®

 2016 Microchip Technology Inc. DS50002437A-page 9

CUSTOMER SUPPORT

Users of Microchip products can receive assistance through several channels:

• Distributor or Representative

• Local Sales Office

• Field Application Engineer (FAE)

• Technical Support

Customers should contact their distributor, representative or field application engineer
(FAE) for support. Local sales offices are also available to help customers. A listing of
sales offices and locations is included in the back of this document.

Technical support is available through the web site at:

http://www.microchip.com/support.

REVISION HISTORY

Revision A (January 2016)

• Original release of this document.

Preface

 2016 Microchip Technology Inc. DS50002437A-page 10

Chapter 1. Product Overview

1.1 INTRODUCTION

The MCP1643 is a compact, high-efficiency, fixed frequency, step-up DC-DC converter
optimized as an LED constant current generator. The device provides an easy-to-use
power supply solution, with a minimum number of external components for applications
powered by one-cell, two-cell Alkaline, NiCd or NiMH batteries.

This chapter provides an overview of the MCP1643 RGB LED Driver Demonstration
Board and covers the following topics:

• MCP1643 Device Overview

• MCP1643 Device Key Features

• MCP1643 RGB LED Driver Demonstration Board Overview

• MCP1643 RGB LED Driver Demonstration Board Features

• What the MCP1643 RGB LED Driver Demonstration Board Kit Includes

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

1.2 MCP1643 DEVICE OVERVIEW

The MCP1643 is a PWM-only device that operates at a fixed 1 MHz switching
frequency. The device has an operating input voltage range from 0.5V to 5V
(V

IN<VLED

For applications that require dimming, the LED can be turned on and off with a
variable duty cycle applied to the EN pin. The maximum dimming frequency is only
limited by the internal soft-start of 240 μs. The device is available in 8-lead MSOP and
8-lead 2x3 mm DFN packages.

), with a 0.65V start-up voltage.

1.3 MCP1643 DEVICE KEY FEATURES

• 1.8A typical peak input current limit

• Up to 550 mA LED load current

• Low start-up voltage: 0.65V (typical, 25 mA LED current, for V

• Low operating input voltage: down to 0.5V

• Maximum input voltage <V

• Maximum output voltage: 5V

• Overvoltage protection (5V)

• Low reference voltage:

-V

= 120 mV

FB

- Minimal power loss on sense resistor

• Pulse-Width Modulation mode operation (1 MHz)

• Internal synchronous rectifier

• Internal compensation

• Inrush current limiting

• Internal soft start (240 μs typical)

• Shutdown (EN=GND):

- True load disconnect

- Dimming control by variable duty cycle

LED

<5.0V

>2.2V)

IN

 2016 Microchip Technology Inc. DS50002437A-page 11

MCP1643 RGB LED Driver Demonstration Board User’s Guide

V

IN

GND

V

FB

C

OUT

4.7 µF

C

IN

4.7 to10 µF

L

1

4.7 µH

SW

LED

4.7



EN

V

OUT

+

-

ALKALINE

ON

OFF

MCP1643

I

LED

= 25 mA

I

LED

=

0.12V
R

SET

R

SET

Power source
1x AA battery

MCP1643

LED driver

RGB
LED

User
input

Controller

Capacitor

PIC16F1455

• Shutdown current: 1.2 μA (typical)

• Overtemperature protection (+150°C, with +25°C hysteresis)

• Packages: 8-lead MSOP and 8-lead 2x3 mm DFN

Figure 1-1 illustrates the typical application with one battery.

FIGURE 1-1: T ypical MCP1643 Boost Converter Single Cell Battery Input.

1.4 MCP1643 RGB LED DRIVER DEMONSTRATION BOARD OVERVIEW

The MCP1643 RGB LED Driver Demonstration Board is used to demonstrate
Microchip Technology’s MCP1643 device in a boost converter application supplied by
one AA battery, or from an external voltage source, which drives each color of the RGB
LED separately at a constant current of 350 mA. A PIC
color of the RGB LED at a frequency of 70 Hz. The MCP1643 RGB LED Driver
Demonstration Board was developed to help engineers reduce product design cycle
time.

The intensity of each color of the LED can be adjusted using individual potentiometers
for each color. The RGB LED is driven by a microcontroller with 3 PWM signals, and
by modifying the duty cycle of each signal, the brightness of each color can be altered.

The MCP1643 RGB LED Driver Demonstration Board is controlled using two buttons:

• Start: to enable the MCP1643 and start the microcontroller

• Stop/Demo: to stop or run a demonstration program

When disabled, the MCP1643 disconnects the path from input to output for
true-disconnect. In this state, the current consumed from the battery is typical 1.2 µA.

DS50002437A-page 12  2016 Microchip Technology Inc.

FIGURE 1-2: MCP1643 RGB LED Driver Demonstration Board B lock Diagram.

®

microcontroller drives each

Product Overview

1.5 MCP1643 RGB LED DRIVER DEMONSTRATION BOARD FEATURES

• Powered by one-cell Alkaline, NiCD, or NiMH battery or by external power supply

• Input voltage range (V

• Start-up voltage: 0.8V at full load

• MCP1643 PWM switching frequency: 1 MHz

• RGB multiplexing frequency: 70 Hz

• Fixed output current for all colors: 350 mA

• Start/Stop functions with push buttons

• Demonstration program

1.6 WHAT THE MCP1643 RGB LED DRIVER DEMONSTRATION BOARD KIT
INCLUDES

The MCP1643 RGB LED Driver Demonstration Board Kit includes the following items:

• MCP1643 RGB LED Driver Demonstration Board (ADM00612)

• Important Information Sheet

): 0.65V to 2V, with V

IN

IN

< V

, after start-up

OUT

 2016 Microchip Technology Inc. DS50002437A-page 13

MCP1643 RGB LED Driver Demonstration Board User’s Guide

NOTES:

DS50002437A-page 14  2016 Microchip Technology Inc.

Chapter 2. Installation and Operation

Start button

Stop/Demo

button

Potentiometer for

the LED’s red color

Potentiometer

for the LED’s

green color

Potentiometer

for the LED’s

blue color

Positive power

supply (+)

Negative power

supply (-)

Programming

header

Green, Blue and Red

Enable signals

EN test point

Switch test

point

LED

Battery slot

2.1 INTRODUCTION

The MCP1643 RGB LED Driver Demonstration Board has been developed for
applications that require driving an LED from a low-voltage source. The low-voltage
technology developed by Microchip Technology allows the device to start up from a low

0.65V input voltage without output overshoot. Also, the device is capable of achieving
high efficiency by integrating the low resistance N-Channel boost switch and the
synchronous P-Channel switch, and by using a low-voltage reference of 0.120V.

Figure 2-1 illustrates the components from the front view.

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

FIGURE 2-1: MCP1643 RGB LED Driver Demonstration Board - Front View.

Figure 2-2 illustrates the components from the back view.

FIGURE 2-2: MCP1643 RGB LED Driver Demonstration Board - Back View.

 2016 Microchip Technology Inc. DS50002437A-page 15

MCP1643 RGB LED Driver Demonstration Board User’s Guide

Power supply

+ -

2.2 GETTING STARTED

The MCP1643 RGB LED Driver Demonstration Board is fully assembled and tested to
evaluate and demonstrate the MCP1643 product operating with an external PWM
signal. This board requires the use of an external power supply or a AA battery.

The package selected for the MCP1643 is the MSOP-8.

2.2.1 Powering the MCP1643 RGB LED Driver Demonstration Board

Soldered test points are available for input voltage connections. The maximum input
voltage should not exceed 2V due to the forward voltage of the LED’s red color of 2.1V.
The forward voltage for the blue and green colors is 3.5V.

After connecting an external power supply or an AA battery, the board enters the
Shutdown mode and only consumes 1.2 µA of current. To start the board, press the

Start push-button. The second push-button has two functions: a short press shuts

down the board, while a long press of more then 0.5 sec puts the board in a temporal
demonstration state.

2.3 BOARD TESTING

Follow these steps to test the board functionalities:

1. Connect the input supply as shown in Figure 2-3,or connect a AA battery in the
battery slot on the back of the board. Please observe the polarity to avoid board
damage.

2. Press the Start push-button to enable the converter. The board will run a start-up

demonstration program with all colors at low brightness, after which the user will
be able to control the brightness. It is recommended to avoid looking directly into
the LED, to prevent eye damage.

3. Change each color brightness by using the three potentiometers marked Red,
Green and Blue, corresponding to each color of the RGB LED.

4. To run the demonstration program, press the Stop/Demo push-button for 0.5s.

5. To stop the MCP1643 RGB LED Driver Demonstration Board, short-press the

Stop/Demo button.

6. Additional test points are available to visualize different signals (FB, output
current, EN, SW).

FIGURE 2-3: MCP1643 RGB LED Driver Demonstration Board Power Supplies.

A 0Ω (R7) resistor is used for bench testing. By removing R7, the soldered test points
can be used to create a wire loop and visualize the current through the LED by using
an oscilloscope current probe.

DS50002437A-page 16  2016 Microchip Technology Inc.

Installation and Operation

2.3.1 How does the MCP1643 RGB LED Driver Demonstration Board

Work?

When the Start button is pressed, the MCP1643 RGB LED Driver Demonstration

Board receives an EN pulse and the device starts switching. When the output voltage
rises above 2.3V, the microcontroller starts, enables the MCP1643 and controls the
RGB LED in order to power each color independently (see Figure 2-4). The amount of
time each LED is ON is set by the user through the three potentiometers.

FIGURE 2-4: RGB LED Enable Signals and LED Current.

An idle time is necessary between each color to ensure that the output voltage of the
MCP1643 is below the LED voltage, otherwise the LED can be damaged by a current
spike caused by the output capacitor discharge. The idle time can be optimized for
different LED voltage differences to increase performance.

 2016 Microchip Technology Inc. DS50002437A-page 17

MCP1643 RGB LED Driver Demonstration Board User’s Guide

2.3.2 MCP1643 as a Voltage Source

In order for the MCP1643 RGB LED Driver Demonstration Board to be a
single-switcher design, the MCP1643 is also used as a voltage source for the control
system; the PIC16F1455 turns on the MCP1643 for a brief period without any LED
connected, but with a resistor divider on V
to increase the output voltage to 4V. This voltage is stored (through a diode) in a
capacitor in order to power the control system while the MCP1643 is driving the LEDs.
The diode is necessary because the energy stored in the capacitors would otherwise
uncontrollably discharge into the LED.

and Feedback. This forces the MCP1643

OUT

FIGURE 2-5: PIC16F1455 Output Voltage and Enable Signal

2.3.3 Programming the PIC16F1455 Microcontroller

The board comes factory-programmed with the demonstration program, and features
a 6-pin 2.54 mm header for future programming. A PICkit
be connected to J3 to program the MCP1643 RGB LED Driver Demonstration Board.

The MPLAB

®

XC8 C Compiler is used to compile the source code and create the hex

file to be used with the reference board. The XC8 compiler is available for download on
the Microchip web site. The source code is rich in comments and helps the user
understand the functionality.

Note: In order to program the MCP1643 RGB LED Driver Demonstration Board,

all potentiometers must be set to the middle position. This is necessary
because the potentiometers use the same data lines as the PICkit 3.

TM

3 In-Circuit Debugger may

DS50002437A-page 18  2016 Microchip Technology Inc.

MCP1643 RGB LED DRIVER

START

Initialize:

-ADC

-interrupts

-Timer 0

Run start-up sequence

Read ADCs

Determine the intensity

SW2 pressed?

SW2 pressed

for > 500 ms?

Run Demonstration

Shutdown sequence:

-RED LED on for 200ms

-STOP MCP1643 enable signal

-SET stop flag

STOP

YES

NO

NO

YES

program

DEMONSTRATION BOARD

USER’ S GUIDE

Chapter 3. Flow Charts

This chapter shows the flow charts for the MCP1643 RGB LED Driver Demonstration
Board.

Figure 3-1 depicts the Main routine flow chart.

FIGURE 3-1: Main Code Sequence.

 2016 Microchip Technology Inc. DS50002437A-page 19

MCP1643 RGB LED Driver Demonstration Board User’s Guide

Timer 0 Interrupt triggered

STOP flag

not set

increment counter

counter >1,

Green

intensity >0

counter =

max Green

interval

counter > max Green

intensity>0

interval + delay,

Blue

counter =
max Blue

interval

counter > max Blue

intensity>0

interval + delay,

Red

counter =
max Red

interval

counter > max Red

interval

STOP MCP1643 Enable

Enable Green LED*

Disable Green LED

Enable Blue LED

Disable Blue LED

Enable Red LED

Disable Red LED

Enable MCP1643 to act

as a voltage source

Enable MCP1643

Disable MCP1643

Enable MCP1643

Disable MCP1643

Enable MCP1643

Disable MCP1643

EXIT Interrupt

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

*The LED must be enabled first so
that the MCP1643 won’t start without
the load connected

YES

Figure 3-2 depicts the Interrupt routine flow chart.

FIGURE 3-2: Interrupt Code Sequence.

DS50002437A-page 20  2016 Microchip Technology Inc.

Appendix A. Schematics and Layouts

A.1 INTRODUCTION

This appendix contains the following schematics and layouts for the MCP1643 RGB
LED Driver Demonstration Board:

• Board – Schematic

• Board – Top Silk

• Board – Top Silk and Copper

• Board – Top Copper

• Board – Bottom Copper

• Board – Bottom Silk and Copper

• Board – Bottom Silk

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

 2016 Microchip Technology Inc. DS50002437A-page 21

DS50002437A-page 22  2016 Microchip Technology Inc.

3

-

5

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CMD_

CMD_G

-

4







5

5

6:

6:

-

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MCP1643 RGB LED Driver Demonstration Board User’s Guide

A.2 BOARD – SCHEMATIC

A.3 BOARD – TOP SILK

A.4 BOARD – TOP SILK AND COPPER

A.5 BOARD – TOP COPPER

Schematics and Layouts

A.6 BOARD – BOTTOM COPPER

A.7 BOARD – BOTTOM SILK AND COPPER

 2016 Microchip Technology Inc. DS50002437A-page 23

MCP1643 RGB LED Driver Demonstration Board User’s Guide

A.8 BOARD – BOTTOM SILK

DS50002437A-page 24  2016 Microchip Technology Inc.

MCP1643 RGB LED DRIVER

DEMONSTRATION BOARD

USER’ S GUIDE

Appendix B. Bill of Materials (BOM)

TABLE B-1: BILL OF MATERIALS (BOM)

Qty. Designator Description Manufacturer Part Number

1 BT1 Battery holder 1 TH AA Keystone

Electronics Corp.

0 C1 Capacitor ceramic. 10000 pF 50V 20% X7R SMD

0603 - DO NOT POPULATE

2 C2, C3 Capacitor ceramic 10 μF 16V 20% Y5V SMD 0805 TDK Corporation C2012Y5V1C106Z

0 C4, C7 Capacitor ceramic 10000 pF 50V 20% X7R SMD

0603 - DO NOT POPULATE

2 C5, C6 Capacitor ceramic 100 μF 10V 20% X5R SMD

1206

1 C10 Capacitor ceramic 1 μF 16V 10% X5R SMD 0603 AVX Corporation 0603YD105KAT2A

1 D1 Diode Schottky PD3S140 490 mV 1A 40V

POWERDI-123

4 J0, J1, J3, J4Conn. TP loop tin SMD Harwin Plc. S1751-46R

TDK Corporation C1608X7R1H103M

AVX Corporation 06035C103KAT2A

TDK Corporation C3216X5R1A107M160AC

Diodes®
Incorporated

1028

PD3S140-7

1 J2 Conn. header-2.54 male 1x6 tin 5.84 MH TH

vertical - DO NOT POPULATE

1 L1 Inductor choke 4.7 uH 1.35A 20% SMD

L2.8W2.8H2.8

1 LD1 Diode LED tri. red, green, blue 2.1V, 3.5V, 3.5V

300 mA, 350 mA, 350 mA SMD TO-252-3

1 PCB1 MCP1643 - Printed Circuit Board — 04-10346-1

4 Q1, Q2, Q3, Q4Transistor FET N-Channel IRLML2402 20V 1.2A

540 mW SOT-23-3

1 R1 Resistor TKF 0.3R 1% 1/4W SMD 1206 Bourns

2 R2, R5 Resistor TKF 10 k 0.1% 1/10W SMD 0603 Panasonic

1 R3 Resistor TKF 47 k 5% 1/10W SMD 0603 Panasonic

1 R4 Resistor TKF 1.3 k 5% 1/10W SMD 0603 Panasonic

1 R6 Resistor TKF 1 k 1% 1/16W SMD 0805 Stackpole

1 R7 Resistor TKF 0R 1% 1/4W SMD 1206 TT Electronics Plc. WCR1206-R005JI

3 R8, R9,

R10

3 R11, R12,

R13

2 SW1, SW2 Switch tactile spst. 12V 50 mA RS285G05A2URT

1 U1 Microchip Analog switcher boost 5V

1 U2 IC MCU 8 bit 14 KB flash 14-lead TSSOP Microchip

Note 1: The components listed in this Bill of Materials are representative of the PCB assembly. The released BOM

used in manufacturing uses all RoHS-compliant components.

Resistor TKF 0R 1/10W SMD 0603 NIC Components

Resistor trimmer Cermet 10K 10% 500 mW TH
3386X

SMD

MCP1643T-I/MS MSOP-8

Sullins Connector
Solutions

Wurth
Elektronik

®

Lumex

Infineon
Technologies AG

Electronics Inc.

Corp.

Bourns Inc. 3386X-1-103TLF

C&K
Components

Microchip
Technology, Inc.

Technology, Inc.

Inc. SML-LX1610RGBW/A

®

, Inc. CRL1206-JW-R300ELF

®

- ECG ERA-3AEB103V

- ECG ERA-3AEB103V

- ECG ERJ-3GEYJ132V

PEC06SAAN

744025004

IRLML2402TRPBF

RMCF 1/10 1K 1% R

3386X-1-103TLF

RS285G05A2URT

MCP1643T-I/MS

PIC16F1455-E/ST

 2016 Microchip Technology Inc. DS50002437A-page 25

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