Microchip Technology MCP1640 User Manual

MCP1640

12V/50 mA Two Cells Input

Boost Converter Reference Design

User’s Guide

© 2011 Microchip Technology Inc. DS51999A

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DS51999A-page 2 © 2011 Microchip Technology Inc.

MCP1640 12V/50 mA TWO CELLS

INPUT BOOST CONVERTER

REFERENCE DESIGN

Table of Contents

Preface ...........................................................................................................................5

Introduction............................................................................................................5

Document Layout .................................................................................................. 5

Conventions Used in this Guide............................................................................ 6

Recommended Reading.............................................................. .. ........................7

The Microchip Web Site........................................................................................ 7

Customer Support.................... .................................... .................. .......................7

Document Revision History................................................................................... 7

Chapter 1. Product Overview

1.1 Introduction .....................................................................................................9

1.2 MCP1640 Short Overview .............................. ......................... .......................9

1.3 What is the MCP1640 12V/50 mA Two Cells Input Boost Converter

Reference D e si g n ? ................................................................................. 11

1.4 What Does the MCP1640 12V/50 mA Two Cells Input Boost Converter

Reference Design Kit Include? ............................ .................. .................11

Chapter 2. Installation and Operation

2.1 Introduction ...................................................................................................13

2.2 Getting Sta rted .... .................................................................................. ....... 15

Appendix A. Schematic and Layouts

A.1 Introduction ..................................................................................................19

A.2 Board – Schematic ... .................................................................... ................ 2 0

A.3 Board – Top Silk and Pads ..........................................................................21

A.4 Board – Top Copper and Pads ....................................................................22

A.5 Board – Bottom Copper and Pads ...............................................................23

Appendix B. Bill of Materials

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

© 2011 Microchip Technology Inc. DS51999A-page 3

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

NOTES:

DS51999A-page 4 © 2011 Microchip Technology Inc.

MCP1640 12V/50 mA TWO CELLS

INPUT BOOST CONVERTER

REFERENCE DESIGN

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 descriptions may differ from those in this document. Please refer to our web site
(www.microchip.com) to obtain the latest documentation available.

Documents are identified with a “DS” number. This number is located on the bottom of each
page, in front of the p age number. The numbering convention for the DS number is
“DSXXXXXA”, where “XXXXX” 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.

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IDE online help.

INTRODUCTION

This chapter contains general information that will be useful to know before using the
MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design. Items
discussed in this chapter include:

• Document Layout

• Conventions Used in this Guide

• Recommended Reading

• The Microchip Web Site

• Customer Support

• Document Revision History

DOCUMENT LAYOUT

This document describes how to use the MCP1640 12V/50 mA Two Cells Input Boost
Converter Refere nce Des ign as a develop ment t ool to ev aluate the MC P1640 de vice’ s
capability to boost low voltages to a high output value, using a single inductor. The
manual layout is as follows:

• Chapter 1. “Product Overview” – Important information about the MCP1640
Input Boost Converter.

• Chapter 2. “Installation and Operation” – Includes instructions on how to get
started with the MCP1640 Input Boost Converter and a description of the User’s
Guide.

• Appendix A. “Schematic and Layouts” – Shows the schematic and layout
diagrams for the MCP1640 Input Boost Converter.

• Appendix B. “Bill of Materials” – Lists the parts used to build the MCP1640
Input Boost Converter.

© 2011 Microchip Technology Inc. DS51999A-page 5

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

CONVENTIONS USED IN THIS GUIDE

This manual uses the following docum entat io n conven tion s:

DOCUMENTATION CONVENTIONS

Description Represents Examples

Arial font:

Italic chara c ters Referenced books MPLAB® IDE User’s Guide

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

Initial caps A window the Output window

A dialog the Settings dialog
A menu selection select Enable Programmer

Quotes A field name in a window or

dialog

Underlined, italic text with
right angle bracket

Bold characters A dialog button Click OK

N‘Rnnnn A number in verilog format,

Text in angle brac kets < > 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 r epeated text var_name [,

A menu path File>Save

A tab Click the Power tab

where N is the tota l number of
digits, R is th e radi x 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’

Choice of mut ually exclus ive
arguments; an OR selection

Represents code supplied by
user

“Save project before build”

4‘b0010, 2‘hF1

any valid filename

[options]
errorlevel {0|1}

var_name...]
void main (void)

{ ...
}

DS51999A-page 6 © 2011 Microchip Technology Inc.

RECOMMENDED READING

This user’s guide describes how to use the MCP1640 12V/50 mA Two Cells Input
Boost Converter Reference Design. Other useful documents are listed below. The
following Microchip document is available and recommended as a supplemental
reference resource.

• MCP1640/B/C/D Data Sheet – “0.65V Start-up Synchronous Boos t Regula tor
with True Output Disconnect or Input/Output Bypass Option” (DS22234)

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

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distributors and factory representatives

Preface

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

DOCUMENT REVISION HISTORY

Revision A (September 2011)

• Initial Release of this Document.

© 2011 Microchip Technology Inc. DS51999 A-page 7

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

NOTES:

DS51999A-page 8 © 2011 Microchip Technology Inc.

MCP1640 12V/50 mA TWO CELLS

Chapter 1. Product Overview

1.1 INTRODUCTION

This chapter provides an overview of the MCP1640 12V/50 mA Two Cells Input Boost
Converter Reference Design and covers the following topics:

• MCP1640 Short Overview

• What is the MCP1640 12V/50 mA Two Cells Input Boost Converter Reference

Design?

• What Does the MCP1640 12V/50 mA Two Cells Input Boost Converter Reference

Design Kit Include?

1.2 MCP1640 SHORT OVERVIEW

The MCP1640 device is a compact, high-efficiency, fixed frequency, step-up DC-DC
converter. It provides an easy-to-use power supply solution, with a minimum number of
external components, for applications powered by one-cell, two-cell, or three-cell
alkaline, NiCd, NiMH, one-cell Li-Ion or Li-Polymer batteries.

The MCP1640/C device automatically selects the best operating mode for efficiency,
PWM (Pulse-Width Modulation) or PFM (Pulse Frequency Modulation). The
MCP1640B/D device is running in PWM mode only and is ideal for noise sensitive
applications. It has a low quiescent current (19 µA, PFM mode typical), a wide input
voltage range (0.35 to 5.5V) and a low start-up voltage (0.65V at 1 mA load current).
The MCP1640 device consumes less than 1 µA in Shutdown mode.

Microchip Technology Inc. provides the MCP1640 device in four variants, which help
engineers to meet different system requirements. The devices and their available
options are presented in Table 1-1.

INPUT BOOST CONVERTER

REFERENCE DESIGN

TABLE 1-1: PART NUMBER SELECTION

True Output

Part Number

MCP1640 X — X —
MCP1640B — X X —
MCP1640C X — — X
MCP1640D — X — X

The MCP1640 is available in SOT23-6 and 8-LD DFN (2x3 mm) packages. For
additional information on the MCP1640 device, refer to the “MCP1640/B/C/D Data
Sheet” (DS22234).

© 2011 Microchip Technology Inc. DS51999A-page 9

PWM/PFM

Mode

PWM

Mode

Disconnect

Shutdown

Option

Input to Output

Bypass

Shutdown

Option

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

1.2.1 MCP1640 Key Features

• Up to 96% Typical Efficiency

• 800 mA Typical Peak Input Current Limit:

-I

-I

-I

• Low Start-up Voltage: 0.65V, typical 3.3V V

• Low Operating Input Voltage: 0.35V, typical 3.3V

• Adjustable Output Voltage Range: 2.0V to 5.5V

• Maximum Input Voltage ≤ V

• Automatic PFM/PWM Operation (MCP1640/C):

- PFM Operation Disabled (MCP1640B/D)

- PWM Operation: 500 kHz

• Low Device Quiescent Current: 19 µA, typical PFM mode

• Internal Synchronous Rectifier

• Internal Compensation

• Inrush Current Limiting and Internal Soft-Start

• Selectable, Logic Controlled, Shutdown States:

- True Load Disconnect Option (MCP1640/B )

- Input to Output Byp a ss Op ti on (MC P16 40 C/D )

• Shutdown Current (All States): < 1 µA

• Low Noise, Anti-Ringing Control

• Overtemperature Protection

> 100 mA @ 1.2V VIN, 3.3V V

OUT

> 350 mA @ 2.4V VIN, 3.3V V

OUT

> 350 mA @ 3.3V V

OUT

5.0V V

IN,

OUT

OUT
OUT
OUT

< 5.5V

OUT

@ 1 mA

@ 1 mA

OUT

L

1

4.7 µH

V

VIN

1.5V

+

Alkaline

-

C

IN

4.7 µF

V

EN

SW

IN

GND

V

OUT

V

FB

536 KΩ

309 KΩ

OUT

3.3V @ 100 mA

C

OUT

10 µF

FIGURE 1-1: Typical MCP1640 Single Cell Input Boost Converter.

DS51999A-page 10 © 2011 Microchip Technology Inc.

Product Overview

1.3 WHAT IS THE MCP1640 12V/50 mA TWO CELLS INPUT BOOST CONVERTER REFERENCE DESIGN?

The MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design is
designed to demonstrate the MCP1640 device’s high-voltage boost capability above its
typical output range of 5.5V. This board boosts the low-voltage input to 12V and up to
70 mA load. By changing the sense resistors (R
output than 12V will be obtained. The MCP1640 Input Boost Converter was developed
to help engineers reduce product design cycle time.

At 2.0V input and 12V o utp ut, th e bo ard is ca p able of a maxi m um of 50mA load current.
The N-MOS switch is connected between the inductor and the main switch, allowing

the application to output higher voltage (see Figure 1-2).
The converter is configured as nonsynchronous; a Schottky diode is connected

between the inductor and the High-Voltage Output (V
starts as the current generator for the Output Capacitor (C
the internal N-MOS switch is OFF, a St art-up Resistor (R
the N-MOS switch, should be used.

L

Two Cell s I npu t

Boost

and RB on Figure 1-2), a lower/higher

T

High). At start-up, MCP1640

OUT

Start

). Because at this time,

OUT

), connected in parallel with

V

OUT

High > 6V

C

IN

N-MOS

Switch

V

IN

SW

EN

FB

V

OUT

GND

R

Start

C

OUT

R

T

R

B

FIGURE 1-2: MCP1640 12V/50 mA Two Cells Input Boost Converter
Reference Design Block Diagram.

1.4 WHAT DOES THE MCP1640 12V/50 mA TWO CELLS INPUT BOOST CONVERTER REFERENCE DESIGN KIT INCLUD E?

The MCP1640 Input Boost Converter kit includes:

• MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design, 102-00386

• Important Information Sheet

Load

© 2011 Microchip Technology Inc. DS51999A-page 11

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

NOTES:

DS51999A-page 12 © 2011 Microchip Technology Inc.

Chapter 2. Installation and Operation

2.1 INTRODUCTION

The MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design is
developed to demonstrate how the MCP1640 device can operate as a high output
voltage DC-DC converter when powered from two batteries. This reference design
allows boosting from the input range of 2.0V-5V to an output higher than 5.5V of the
typical MCP1640 application. High-voltage outputs, such as 9V, 12V or 24V, can be
generated from just two alkaline cells.

For this reference design, the output voltage is set at 12V. Typically, a minimum of a
50 mA load can be supported from a 2.0V input. The board can deliver more output cur­rent (up to 70 mA) if it is powered with 3.0V. A small 3x3x1 mm inductor offers a good
efficiency of up to 75%. Good converter stability is obtained with the B option of
MCP1640 (PWM Mode Only and True Output Disconnect options).

2.1.1 Board Features

MCP1640 12V/50 mA TWO CELLS

INPUT BOOST CONVERTER

REFERENCE DESIGN

The MCP1640 Input Boost Converter has the following features:

• Input Voltage: Two Alkaline or Lithium Cells, 2.0-3.0V Typical

- Supports extended input range of 2.0V-5.0V

• Output Capability:

- Dependent on the input voltage

- 12V/50 mA typical @ 2.0V input

- 12V/70 mA @ 3.3V input

• No Load Input Current: 0.2 mA @ 3.0V Input

• Efficiency: up to 75%

• PWM Operation at 500 kHz

© 2011 Microchip Technology Inc. DS51999A-page 13

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

50.0

20

u

80.0

75.0

70.0

65.0

60.0

55.0

VIN = 2.4V

VIN = 3.0V

Efficiency (%)

45.0

40.0

10 20 30 40 50

Load Current (mA)

FIGURE 2-1: Efficiency vs. Load Current for 12V Output at 2.4V and

3.0V Input.

80

70

60

50

40

30

m Load Current (mA)

10

Maxim

0

2 2.4 2.8 3.2 3.6

Input Voltage (V)

FIGURE 2-2: Maximum Load Current vs. Input Voltage at 12V Output.

DS51999A-page 14 © 2011 Microchip Technology Inc.

2.2 GETTING STARTED

The MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design is fully
assembled and tested to evaluate and demonstrate the MCP1640 family of products.

2.2.1 Powering the MCP1640 12V/50 mA Two Cells Input Boost
Converter Reference Design

The extended input range of the MCP1640 Input Boost Converter is 2.0 to 5.0V input.
Good efficiency is obtained by supplying from two cells (primary and secondary batter­ies).

Input power connectors are placed on the left side of the board:

•V

for positive power

IN

• GND for negative power

The maximum input voltage should not exceed 5.0V. The output voltage will be out of
regulation for input voltages lower than 2.0V.

The output connector is called V
current is 50 mA when the board is powered by two alkaline batteries that are close to
the end of their run time, at approximately 1V each.

2.2.2 Board Testing

Installation and Operation

and is referenced to GND. The minimum output

OUT

Set 3.0V

PWR Supply

Because this board is boosting the input voltage, the input current is greater than the
output current. The variable power supply for testing requires output capability of at
least 1A and a voltage range of 2.0V to 5V.

To test the board, follow these steps:

1. Connect the power at V

and GND terminals of the board.

IN

2. Set the power supply to 3.0V.

3. Connect a voltmeter and a 240Ω/0.5W resisto r betw een V

and GND

OUT

connectors, as shown in Figure 2-3.

4. Check to be sure the voltmeter indicates 12V.

5. Set the power supply to 2.0V and verify if the output of the converter stays

regulated (V

OUT

=12V).

V-meter

R

240R/0.5W

FIGURE 2-3: MCP1640 12V/50 mA Two Cells Input Boost Converte r Reference Design
Setup Circuit.

© 2011 Microchip Technology Inc. DS51999A-page 15

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

The board has several test points that help engineers analyze the switch node’s
waveforms or MCP1640’s output:

• The high-voltage switch node test point (SWH).

• The test point of the MCP1640 device’s switch node (SWL).

• VO test point shows the MCP1640 device’s V
The difference between SWH and SWL signals is their amplitude. For 12V output, the

amplitude of SWL is approximately 5V, while SWH shows the sum of MCP1640's SW
node (SWL signal) and external n-channel MOS voltage.

Figures 2-4 and 2-5 show the Discontinuous (25 mA load for 2.4V V
mode waveforms (60 mA load at 2.4V V

, where the inductor peak current is close to

IN

the maximum input peak current limit of the MCP1640 device, 800 mA). Once the
800 mA limit is reached, V
value of the inductor current (I

value is decreasing (goes out of regulation). The mean

OUT

) is equal for a boost converter with the input current

L

(except the current consumption of MCP1640).

pin (this output is unregulated).

OUT

) and Continuous

IN

FIGURE 2-4: MCP1640 12V/50 mA Two Cells Input Boost Converter
Reference Design Test Points (SWH, SWL), Inductor (I_L) and Load Current (I_OUT)
Waveforms for 25 mA Load and 2.4V Input in Discontinuous Mode.

DS51999A-page 16 © 2011 Microchip Technology Inc.

Installation and Operation

FIGURE 2-5: MCP1640 12V/50 mA Two Cells Input Boost Converter
Reference Design Test Points (SWH, SWL), Inductor (I
Waveforms for 60 mA Load and 2.4V Input in Continuous mode.

) and Load Current (I

L

OUT

)

2.2.3 How Does the MCP1640 12V/50 mA Two Cells Input Boost
Converter Reference Design Works?

The board was designed to boost low voltage from two alkaline cells or NiCd/NiMH
cells to high voltage. The topology used in this reference design is adapting a
low-voltage boost converter into a high-voltage boost converter using a single inductor,
instead of using a flyback topology that requires a more expensive flyback transformer.
Another advantage is that the switching voltage spikes are kept below the safe value,
6V, for MCP1640 device’s SW pin.

The converter is configured as nonsynchronous; an external diode, D, is connected
between the inductor and the high-voltage output (V

The two sense resistors, R

and RB, set the output (V

T

following equation:

EQUATION 2-1:

V

OUT

R

=

T

⎛⎞

R

------------ -1–

×

B

⎝⎠

V

FB

Where:

VFB=1.21V

= Reference voltage of the FB pin

V

FB

V

= 12.0V

OUT

R

= Resisto r’s value is selected by the designer

B

).

OUT

) at 12.0V according to the

OUT

Note: The reference board is tested up to 24V output with a maximum load of

20 mA. The internal error amplifier is a transconductance type; its gain is
not related to the feedback resistors’ values.

© 2011 Microchip Technology Inc. DS51999A-page 17

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

Attention should be paid to the values of the sense resistors. When testing the board
for other output voltage, a potential issue with higher value resistors is environmental
contamination, which can create a leakage current path on the PCB. This will affect the
feedback voltage and the output voltage regulation. Engineers should use resistors that
are larger than 1 MΩ with precaution. In normal humidity conditions, the V
leakage is very low and the resistors’ values will not affect the stability of the system.

When the board is powered up, the internal MCP1640 device’s start-up logic circuitry
turns the internal rectifying switch on until the output capacitor, connected at the V
pin (C
switch limits the maximum current. Because at start-up, the external n-channel MOS
(Q) transi stor i s OFF, a start-up res istor (R
MCP1640 starts switching, and the external N-MOS is turned on, cascading the
internal N-MOS switch of the MCP1640 to work with high voltage, more than 6V.

Notice that the MCP1640 is working internally as a synchronous rectifier and delivers
on its output (Pin 5) a part of the total output power. This output is unregulated because
the sense resistors, R
MCP1640 gets its start-up bias from V
comes from the output. The C
of MCP1640. This voltage is used to supply the internal blocks after start-up (including
the compensation circuitry). In case of instability, a few mA loads may be required (R
is not populated on the board; for 12V output, use a 2k or 3k resistor). On the output of
MCP1640 (VO test point), a maximum 5 mA load can be connected. Exceeding the
load produces unregulated board V

The board works well in Discontinuous mode. However, once entered into Continuous
mode, V

There is no undervoltage lockout feature for the MCP1640 family of devices. The
device will start up at the lowest voltage possible and run down to the lowest voltage
possible.

), is charged to a value close to the input voltage. During start-up, the rectifying

L

) is bypassing it and the CL cap is supplied.

S

and RB, are connected to the high output voltage. The

T

goes out of regulation.

OUT

capacitor is mandatory, because it smooths the output

L

. Once the ou tput exceeds the input, bias

IN

.

OUT

FB

input

OUT

L

Note: Because this configuration is an nonsynchronous converter, the MCP1640

device’s features, true disconnect output and short-circuit protection, will be
lost for this reference board. In case of a short circuit, inductor L, and diode
D, can be broken. Notice that the MCP1640 will not be affected.

DS51999A-page 18 © 2011 Microchip Technology Inc.

Appendix A. Schematic and Layouts

A.1 INTRODUCTION

This appendix contains the following schematics and layouts for the MCP1640 12V/50 mA
Two Cells Input Boost Converter Reference Design:

• Board – Schematic

• Board – Top Silk and Pads

• Board – Top Copper and Pads

• Board – Bottom Copper and Pads

MCP1640 12V/50 mA TWO CELLS

INPUT BOOST CONVERTER

REFERENCE DESIGN

© 2011 Microchip Technology Inc. DS51999A-page 19

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

A.2 BOARD – SCHEMATIC

VOUT

OUT

10µ

C

12

VIN

VOUT

2µ2

MCP1640

4μ7L

10µ

CIN

in case of instabili ty,

use 2k o r 3k re sis tors

No te s:

* Do not populate -

DS51999A-page 20 © 2011 Microchip Technology Inc.

A.3 BOARD – TOP SILK AND PADS

Schematic and Layouts

© 2011 Microchip Technology Inc. DS51999A-page 21

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

A.4 BOARD – TOP COPPER AND PADS

DS51999A-page 22 © 2011 Microchip Technology Inc.

A.5 BOARD – BOTTOM COPPER AND PADS

Schematic and Layouts

© 2011 Microchip Technology Inc. DS51999A-page 23

MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design

NOTES:

DS51999A-page 24 © 2011 Microchip Technology Inc.

MCP1640 12V/50 mA TWO CELLS

INPUT BOOST CONVERTER

REFERENCE DESIGN

Appendix B. Bill of Mater ials

TABLE B-1: BILL OF MATERIALS (BOM)

Qty Reference Description Manufacturer Part Nu mber

1C

IN

1C

OUT

1C

L

1 D SCHOTTKY RECT. 40V 0.5A SOD323 NXP Semiconductors PMEG4005AEA,115
0 J1, J2 DO NOT POPULATE

1 L INDUCTOR POWER 4.7 µH 1.1A SMD TDK Corporation VLS3015ET-4R7M
1 PCB RoHS-compliant bare PCB, MCP1640

1 Q MOSFET N-CH 30V 2.2A SSOT3 Fairchild Semiconductor
1R

E

1R

S

0R

L

1R

B

1R

T

1 U1 MCP1640 PWM Synchronous Boost

4V

4 — 3M – SJ5382TRANS – FEET, STICK ON,

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

, V

IN

OUT

GND(s)

BOM, used in manufacturing, uses all RoHS-compliant components.

CAP. CER 10 µF 6.3V X5R 20% 0603 TDK® Corporation C1608X5R0J106M
CAP. CER 10 µF 16V X5R 0805 TDK Corporation C2012X5R1C106M
CAP. CER 2.2 µF 6.3V X5R 20% 0603 TDK Corporation C1608X5R0J225M

CONN. HEADER 2POS .100" R/A TIN

12V/50 mA Two Cells Input Boost
Converter Reference Design

RES. 1.0M OHM 1/10W 5% 0603 SMD Panasonic® – ECG ERJ-3GEYJ105V
RES. 300 OHM 1/10W 5% 0603 SMD YAGEO
DO NOT POPULATE

RES. 1.0k OHM 1/10W 5% 0603 SMD
RES. 180k OHM 1/10W .5% 0603 SMD YAGEO RT0603DRD07180KL
RESISTOR 1.60M OHM 1/10W 1% 0603 Panasonic – ECG ERJ-3EKF1604V

Converter – SOT23-6

,

PC TEST POINT TIN SMD Harwin PLC. S1751-46R

PK144

(1)

®

Molex

— 104-00386

®

Panasonic – ECG ERJ-3GEYJ102V

Microchip Technology Inc. MCP1640BT-I/CHY

3M SJ5382TRANS

90121-0122

®

FDN337N

RC0603JR-07300RL

© 2011 Microchip Technology Inc. DS51999A-page 25

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08/02/11

DS51999A-page 26 © 2011 Microchip Technology Inc.

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