MCP73871
Demo Board
with Voltage Proportional
Current Control
User’s Guide
© 2009 Microchip Technology Inc.
DS51812B
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•
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•
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•
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DS51812B-page 2
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL CURRENT
CONTROL USER’S GUIDE
Table of Contents
Preface ........................................................................................................................... 1
Introduction............................................................................................................ 1
Document Layout .................................................................................................. 1
Conventions Used in this Guide ............................................................................ 2
Recommended Reading........................................................................................ 3
The Microchip Web Site ........................................................................................ 3
Customer Support ................................................................................................. 3
Document Revision History ................................................................................... 3
Chapter 1. Product Overview
1.1 Introduction ..................................................................................................... 5
1.2 What is the MCP73871 Demo Board with Voltage Proportional Current
Control? .................................................................................................... 6
1.3 What the MCP73871 Demo Board with Voltage Proportional Current Control
kit Includes? .............................................................................................. 6
Chapter 2. Installation and Operation
2.1 Introduction ..................................................................................................... 7
2.2 Features ......................................................................................................... 7
2.3 Getting Started ............................................................................................... 8
Appendix A. Schematic and Layouts
A.1 Introduction .................................................................................................. 13
A.2 Board – Schematic ....................................................................................... 14
A.3 Board – Top Silk and Pads .......................................................................... 15
A.4 Board – Top Metal Layer ............................................................................. 16
A.5 Board – Bottom Layer .................................................................................. 17
Appendix B. Bill of Materials (BOM)
Worldwide Sales and Service .................................................................................... 20
© 2009 Microchip Technology Inc.
DS51812B-page 3
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
NOTES:
DS51812B-page 4
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL
CURRENT CONTROL 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 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 page 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® IDE on-line help.
Select the Help menu, and then Topics to open a list of available on-line help files.
INTRODUCTION
This chapter contains general information that will be useful to know before using the
MCP73871 Demo Board with Voltage Proportional Current Control. 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 MCP73871 Demo Board with Voltage
Proportional Current Control as a linear Li-Ion battery charge controller that can share
a load. The manual layout is as follows:
• Chapter 1. “Product Overview” – Important information about the MCP73871
Demo Board with Voltage Proportional Current Control.
• Chapter 2. “Installation and Operation” – Includes instructions on how to get
started with this user’s guide and a description of the user’s guide.
• Appendix A. “Schematic and Layouts” – Shows the schematic and layout
diagrams for the MCP73871 Demo Board with Voltage Proportional Current
Control.
• Appendix B. “Bill of Materials (BOM)” – Lists the parts used to build the
MCP73871 Demo Board with Voltage Proportional Current Control.
© 2009 Microchip Technology Inc.
DS51812B-page 5
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Arial font:
Italic characters
Represents
Referenced books
Emphasized text
A window
A dialog
A menu selection
A field name in a window or
dialog
A menu path
MPLAB® IDE User’s Guide
...is the only compiler...
the Output window
the Settings dialog
select Enable Programmer
“Save project before build”
A dialog button
A tab
A number in verilog format,
where N is the total number of
digits, R is the radix and n is a
digit.
A key on the keyboard
Click OK
Click the Power tab
4‘b0010, 2‘hF1
Italic Courier New
Sample source code
Filenames
File paths
Keywords
Command-line options
Bit values
Constants
A variable argument
Square brackets [ ]
Optional arguments
Curly brackets and pipe
character: { | }
Ellipses...
Choice of mutually exclusive
arguments; an OR selection
Replaces repeated text
#define START
autoexec.bat
c:\mcc18\h
_asm, _endasm, static
-Opa+, -Opa0, 1
0xFF, ‘A’
file.o, where file can be
any valid filename
mcc18 [options] file
[options]
errorlevel {0|1}
Initial caps
Quotes
Underlined, italic text with
right angle bracket
Bold characters
N‘Rnnnn
Text in angle brackets < >
Courier New font:
Plain Courier New
Represents code supplied by
user
DS51812B-page 6
Examples
File>Save
Press <Enter>, <F1>
var_name [,
var_name...]
void main (void)
{ ...
}
© 2009 Microchip Technology Inc.
Preface
RECOMMENDED READING
This user's guide describes how to use MCP73871 Demo Board with Voltage
Proportional Current Control. Other useful documents are listed below. The following
Microchip documents are available and recommended as supplemental reference
resources.
• MCP73871 Data Sheet - “Stand-Alone System Load Sharing and Li-Ion /
Li-Polymer Battery Charge Management Controller”, DS22090
This data sheet provides detailed information regarding the MCP73871 product family.
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
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://support.microchip.com.
© 2009 Microchip Technology Inc.
DS51812B-page 7
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
DOCUMENT REVISION HISTORY
Revision B (November 2009)
Initial Release of this Document.
• Updated Section 2.2 “Features” with information on the Voltage Proportional
Current Control Input Voltage.
• Added footnote to Table 2-1.
• Updated Section 2.3.3 “Voltage Proportional Charge Control (VPCC)
Function”.
• Added Section 2.3.3.1 “Example”.
Revision A (April 2009)
• Initial Release of this Document.
DS51812B-page 8
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL
CURRENT CONTROL USER’S GUIDE
Chapter 1. Product Overview
1.1
INTRODUCTION
The MCP73871 Demo Board with Voltage Proportional Current Control is designed to
demonstrate Microchip's stand-alone linear Li-Ion battery charger with system power
path and load sharing management control solution. The MCP73871 integrates the
required elements to meet design challenges when developing new Li-Ion / Li-Polymer
batteries powered products.
The MCP73871 requires minimum external components to power the system load and
charge single cell Li-Ion batteries independently. When input power is absent or
insufficient, the Li-Ion battery becomes the primary power source and supports the
required system load current. The MCP73871 Demo Board with Voltage Proportional
Current Control feature added is developed to assist engineers in reducing product
design cycle and time by utilizing Microchip’s favorite stand-alone Li-Ion battery
charger and system load sharing management controller.
This chapter provides an overview of the MCP73871 Demo Board with Voltage
Proportional Current Control and covers the following topics:
• What is the MCP73871 Demo Board with Voltage Proportional Current Control?
• What the MCP73871 Demo Board with Voltage Proportional Current Control Kit
includes?
AC-DC Adapter
or USB Port
MCP73871
18, 19
10 μF
330 kΩ
OUT
470Ω
6
470Ω
7
470Ω
8 STAT1
LBO
2
3
Low Hi
110 kΩ
IN
4
Low Hi
9
Low Hi
17
Low Hi
PG
STAT2
OUT
VBAT
VBAT_SENSE
THERM
1, 20
System
Load
4.7 μF
14, 15, 16
4.7 μF
5
NTC
VPCC
SEL
PROG2
PROG1
TE
PROG3
CE
VSS
13
12
RPROG1
Single-Cell
Li-Ion
Battery
10 kΩ
RPROG3
10,11 (EP)
FIGURE 1-1:
MCP73871 With System Power Path and Voltage Proportional Current Control
(VPCC) Management Typical Application.
© 2009 Microchip Technology Inc.
DS51812B-page 9
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
1.2
WHAT IS THE MCP73871 DEMO BOARD WITH VOLTAGE PROPORTIONAL
CURRENT CONTROL?
The MCP73871 Demo Board with Voltage Proportional Current Control demonstrates
the features of Microchip’s MCP73871 “Stand-Alone System Load Sharing and Li-Ion
/ Li-Poly Battery Charge Management Controller”.The MCP73871 Demo Board with
Voltage Proportional Current Control is designed to deliver minimum 1.5A total current
to system load and to a single cell Li-Ion battery at 4.2V preset voltage regulation (4.1V,
4.35V and 4.4V options are also available for MCP73871). The MCP73871 Demo
Board with Voltage Proportional Current Control has one dip switch (S1) with four poles
to control input current limits, enable charge timer and enable charging. The first switch
decides the input power source between AC-DC wall adapter and USB port (AC/USB).
The second switch of S1 determines the 500 mA high-power USB port or the 100 mA
low-power USB port (High/Low), if the first switch of S1 is enabled (ON). The input
current limit is governed by the USB specification when selecting USB on S1 switch.
The maximum fast current when AC is selected on S1 is programmed by the resistor
RPROG1 at 1A, and the termination current is set at 100 mA by RPROG3
(see Figure 1-1).
The MCP73871 Demo Board with Voltage Proportional Current Control offers three
status LED (for charge status outputs and a power-good indicator).
Note:
Refer to Table 2-1 for charge status outputs and Figure 2-1 for charge
current setups.
The MCP73871 Demo Board with Voltage Proportional Current Control comes with a
factory preset low-battery indicator (LBO) when input is absent. The preset value is
3.2V and STAT1 LED (Green) will turn ON if the battery voltage is below the threshold
voltage.
The MCP73871 Demo Board with Voltage Proportional Current Control is designed to
cover all the features of the MCP73871 device. A thermistor can be added at test points
TP6 and TP7, but resistor R6 must be removed (see the A.2 “Board – Schematic”).
The board layout easily permit to change the two programmable resistors: RPROG1 and
RPROG3.
1.3
WHAT THE MCP73871 DEMO BOARD WITH VOLTAGE PROPORTIONAL
CURRENT CONTROL KIT INCLUDES?
This MCP73871 Demo Board with Voltage Proportional Current Control kit includes:
• One MCP73871 Demo Board with Voltage Proportional Current Control,
102-00244
• Important Information "Read First"
DS51812B-page 10
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL
CURRENT CONTROL USER’S GUIDE
Chapter 2. Installation and Operation
2.1
INTRODUCTION
The MCP73871 Demo Board with Voltage Proportional Current Control demonstrates
Microchip's standalone linear Li-Ion battery charger with system power path and load
sharing management control solution. The system load is also powered by the Li-Ion
battery when the input power is disconnected. A number of device options allow the
MCP73871 to be utilized in a variety of applications. Please refer to the MCP73871
Data Sheet (DS22090) and/or contact local Microchip supports for additional device
options.
Typical applications for the reference design are in Smart Phones, PDA, Portable
Media Players, MP3 Players, Digital Cameras, Handheld Medical devices, Bluetooth
headsets, Ultra-Mobile PC and Portable Communicators.
2.2
FEATURES
The MCP73871 Demo Board with Voltage Proportional Current Control has the
following features:
• Integrated System Load Sharing
• Voltage Proportional Current Control (VPCC) Input voltage: 5.5V with ±0.5V
tolerance (additional information available in the MCP73871 Data Sheet)
• Input Current Limit Control hardware selected (typical 1650 mA, USB-High
maximum 500 mA, and USB-Low maximum 100 mA)
• Three LEDs to indicate charge status, low battery and power good signal
• Preset Li-Ion battery charge voltage: 4.2V ± 0.5%
• Temperature monitoring is disabled by default, but can be enabled to use with a
NTC thermister (tied at TP6 and TP7 and removing R6)
• Factory preset 0.1C preconditioning current of deeply depleted cells
• Factory preset Safety Timer with Timer Enable feature (by S1 switch)
• Constant Current/Constant Voltage (CC/CV) charge algorithm
• Resistor programmed maximum charge current (RPROG1): 1A
• Resistor programmed termination set point (RPROG3): 100 mA
• Automatic Charge Termination
• Automatic Recharge
• Internal Thermal Regulation
• Exposed Pad with extra via underneath for better heat dissipations
© 2009 Microchip Technology Inc.
DS51812B-page 11
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
2.3
GETTING STARTED
The MCP73871 Demo Board with Voltage Proportional Current Control is fully
assembled and tested for charging a single-cell Li-Ion or Li-Polymer battery with or
without system load.
2.3.1
Power Input and Output Connection
2.3.1.1
POWERING THE MCP73871 DEMO BOARD WITH VOLTAGE
PROPORTIONAL CURRENT CONTROL
1. Connect the positive battery terminal to VBAT+ (TP4) and negative battery
terminal to GND (TP1 or TP5).
2. Connect the 5V – 6V DC power supply Negative Terminal to GND (TP1 or TP5).
3. Connect the 5V – 6V DC power supply Positive Terminal to VDD (TP2).
4. Connect positive of load to OUT (TP3) on the board and negative of load to GND
(TP1 or TP5). The system load can be a power resistor or E-Load.
5. The maximum current that system load requires should not violate the
specification of Li-Ion battery manufacturer (typical at 1C or less) or 1A for safety
and performance concerns.
6. You should initiate the battery charging cycle when turning CE switch of S1 OFF.
Turning the CE switch ON disables the Li-Ion battery charger function.
7. The S1 switch #1 in OFF position (SEL - “AC-DC”) allows maximum input current
of 1.8A to support both system load and Li-Ion battery charger at 1000 mA fast
charge current rate.
8. The S1 switch #1 in ON position (SEL - “USB”) limits the input current to meet
USB specifications.
9. If switch SEL is in ON position (PROG2), the user has two options for switch #2:
- OFF - limits the total input current to 500 mA
- ON - for maximum input current at 100 mA.
Note 1:
For setup/configuration follow the information in Table 2-2.
2:
Fast Charge Current and Termination Current can be easily programmed
with various resistors based on Figure 2-1.
3:
The Li-Ion battery pack can be replaced with test circuit or electronic load
that can sink current with DC power supply. Refer to Figure 2-2 for
details.
10. If DC power is removed, the load should be supported by the Li-Ion battery.
2.3.2
Programming Resistors
The resistors that connected at RPROG1 and RPROG3 pins select the maximum charge
current in constant current mode from ac-dc adapter and termination current,
respectively. The relationship between fast charge current and value of RPROG1
resistor is illustrated in Figure 2-1. The correspondence of RPROG1 on MCP73871
Demo Board with Voltage Proportional Current Control is R1. The default value is 1 kΩ,
which sets the maximum charge current at 1A.
For RPROG3, the correspondent resistor is R2. A 10 kΩ resistor sets the charge
termination current at 100 mA and a 100 kΩ value results a 10 mA termination point.
Read carefully the additional information on the schematic in A.2 “Board – Schematic”. The boards comes with R2 =10 kΩ.
DS51812B-page 12
© 2009 Microchip Technology Inc.
Installation and Operation
Charge Current (mA)
1000
900
800
700
600
500
400
300
200
100
0
1
1
3
5
7
9
11
13
15
17
19
Programming Resistor (kΩ)
FIGURE 2-1:
(RPROG1).
MCP73871 Charge Current (IOUT) vs. Programming Resistor
Amp
Meter
0V – 5V
Power
Source
Volt
Meter
R
5Ω
10W
© 2009 Microchip Technology Inc.
Microchip
Battery
Charge
Management
Controller
100 μF
GND
FIGURE 2-2:
VBAT+
VBAT-
Simulated Battery Load.
DS51812B-page 13
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
5V DC
Power Supply
min 2A
Resistive Load
or
E-Load
Battery or
Battery
Emulation
Circuit
FIGURE 2-3:
MCP73871 Top Board and Application Circuit.
TABLE 2-1:
MCP73871 CHARGE STATUS OUTPUTS
STAT1 (Green)
STAT2 (Red)
PG (Blue)
Shutdown
Charge Cycle State
OFF
OFF
OFF
Standby
OFF
OFF
ON
Charge in Progress
ON
OFF
ON
Charge Complete (EOC)
OFF
ON
ON
Temperature Fault
ON
ON
ON
Timer Fault
ON
ON
ON
Low Battery Indicator (LBO)
ON
OFF
OFF
No Battery Present
OFF
OFF
ON
No Input Power
OFF
OFF
OFF
Note:
TABLE 2-2:
LED Status Outputs are given for the battery connected at VBAT and GND.
MCP73871 DEMO BOARD DIP SWITCH CONFIGURATION
Switch # / Name
State / Function
OFF
Observations
ON
1 / SEL
AC-DC Adapter
Power from USB
—
2 / PROG2
USB maximum 500 mA
USB max 100 mA
Only if SEL is ON
3 / TE
Timer Enable OFF
Timer Enable activated
Factory preset at 4h, 6h and 8h
4 / CE
Charge is enabled
Charge function OFF
CE = Chip Enable
DS51812B-page 14
© 2009 Microchip Technology Inc.
Installation and Operation
2.3.3
Voltage Proportional Charge Control (VPCC) Function
If the input voltage drops to a preset value, determined by the threshold established at
the VPCC input (1.23V at pin #2), due to a limited amount of input current or input
source impedance, the battery charging current is reduced. The VPCC control tries to
reach a steady state condition where the system load has priority and the battery is
charged with the remaining current. Therefore, if the system demands more current
that the input can provide, the MCP73871 changes its status and the battery is able to
supplement the input current to the system load.
The VPCC function sustains the system load as its highest priority. It does this by
reducing the noncritical charge current while maintaining the maximum power output
of the adapter. Further demand from the system is supported by the battery, if possible.
The VPCC feature functions are identical for USB port or AC-DC adapter inputs. This
feature can be disabled by removing resistor R7 and replacing R8 with a zero ohms
0603 resistor.
The demo board is designed to operate with 5.5V with +/-0.5V tolerance input voltage,
by setting accordingly the voltage on VPCC pin by R7 and R8 resistors (see
A.2 “Board – Schematic”). Additional information on the configuration of the VPCC
function is available in the MCP73871 Data Sheet.
2.3.3.1
EXAMPLE
A system is designed with a 5.0V rated DC power supply with ±0.5V tolerance. The
worst condition of 4.5V is selected, which is used to calculate the VPCC supply voltage
with divider. The voltage divider equation is shown below:
R7
VPCC = --------------------- × V DDmin
R7 + R8
110k
1.23V = -------------------------- × 4.5V
110k + R8
R8 = 292.43k Ω
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
VBAT
VVPCC
IIN
3.5
4
4.5
Input Voltage (V)
5
Input Current (A)
Battery Volatge (V)
VPCC pin Voltage (V)
The calculated R8 equals to 292.43 kΩ when 110 kΩ is selected for R7. The 294 kΩ
resistor is selected for R8 to build the voltage divider for VPCC pin.
Figure 2-4 illustrates the influence of various input voltages.
5.5
FIGURE 2-4:
Input and Output Parameters when Input Voltage is Variable,
from 2.5V to 5.5V. See the Influence of VPCC Pin.
© 2009 Microchip Technology Inc.
DS51812B-page 15
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
2.3.4
Temperature Monitoring Option
The MCP73871 device monitors continuously the battery temperature during a charge
cycle by measuring the voltage between the THERM and VSS pins. An internal current
source provides the bias for most common 10 kΩ negative-temperature coefficient
thermistors (NTC). The MCP73871 device compares the voltage at the THERM pin to
factory set thresholds of 1.24V and 0.25V, typically. Once a voltage outside the
thresholds is detected during a charge cycle, the MCP73871 device immediately
suspends the charge cycle, by turning off the charge and holding the timer value. The
charge cycle resumes when the voltage at the THERM pin returns to the normal range.
To activate this feature, remove R6 resistor and connect a 10 kΩ NTC thermistor to TP6
and TP7 test points.
5
1
4
0.8
3
Cell Temperature / 10
2
0.6
0.4
ICharge
1
0.2
0
0
25
50
75
100
125
Charge Current (A)
Battery Volatge (V)
Cell Temperature / 10
(°C)
VBAT
0
150
Time (min)
FIGURE 2-5:
MCP73871 Charge Profile in Constant Voltage Mode for a
900 mAh Li-Ion Cell.
DS51812B-page 16
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL
CURRENT CONTROL USER’S GUIDE
Appendix A. Schematic and Layouts
A.1
INTRODUCTION
This appendix contains the following schematics and layouts for the MCP73871 Demo
Board with Voltage Proportional Current Control:
•
•
•
•
Board – Schematic
Board – Top Silk and Pads
Board – Top Metal Layer
Board – Bottom Layer
© 2009 Microchip Technology Inc.
DS51812B-page 17
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
BOARD – SCHEMATIC
M
A.2
DS51812B-page 18
© 2009 Microchip Technology Inc.
Schematic and Layouts
A.3
BOARD – TOP SILK AND PADS
© 2009 Microchip Technology Inc.
DS51812B-page 19
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
A.4
BOARD – TOP METAL LAYER
DS51812B-page 20
© 2009 Microchip Technology Inc.
Schematic and Layouts
A.5
BOARD – BOTTOM LAYER
© 2009 Microchip Technology Inc.
DS51812B-page 21
MCP73871 Demo Board with Voltage Proportional Current Control User’s Guide
NOTES:
DS51812B-page 22
© 2009 Microchip Technology Inc.
MCP73871 DEMO BOARD WITH
VOLTAGE PROPORTIONAL
CURRENT CONTROL USER’S GUIDE
Appendix B. Bill of Materials (BOM)
TABLE B-1:
Qty
BILL OF MATERIALS (BOM)
Reference
Description
Manufacturer
Part Number
3
C1, C2, C3
CAP CERAMIC 4.7 uF 10 X5R 0603
Taiyo Yuden®
LMK107BJ475KA-T
1
LED1
True Green Water Clear 0603 SMD
LED
Para Light USA
L-C191LGCT-U1
1
LED2
Super Red Water Clear 0603 SMD
LED
Para Light USA
L-C191KRCT-U1
1
LED3
Blue Water Clear 0603 SMD LED
Para Light USA
L-C191LBCT-U1
1
PCB
RoHS Compliant Bare PCB,
MCP73871 Demo Board w/ Voltage
Proportional Current Control
Advanced Circuits
104-00244
4
R1, R3, R4, R5
RES 1K OHM 1/10W 1% 0603 SMD
Panasonic® - ECG
ERJ-3EKF1001V
2
R2, R6
RES 10K OHM 1/10W 1% 0603 SMD Panasonic - ECG
ERJ-3EKF1002V
5
R7, R9, R10,
R11, R12
RES 110K OHM 1/10W 1% 0603
SMD
Panasonic - ECG
ERJ-3EKF1103V
1
R8
RES 330K OHM 1/10W 5% 0603
SMD
Panasonic - ECG
ERJ-3GEYJ334V
1
S1
SWITCH DIP TAPE SEALED 4POS
SMD
C&K Components
SDA04H0SB
5
TP1, TP2, TP3,
TP4, TP5
PC Test Point Compact SMT
Keystone
Electronics®
5016
1
U1
Stand-Alone System Load Sharing
and Li-Ion / Li-Polymer Battery
Charge Management Controller
Microchip
Technology Inc.
MCP73871-2CCI/ML
4
Bump
BUMPON HEMISPHERE .44X.20
WHITE
3M
SJ5003-9-ND
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.
© 2009 Microchip Technology Inc.
DS51812B-page 23
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
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EUROPE
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Tel: 65-6334-8870
Fax: 65-6334-8850
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Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
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Tel: 886-3-6578-300
Fax: 886-3-6578-370
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
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Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
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Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
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Fax: 44-118-921-5820
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Tel: 86-756-3210040
Fax: 86-756-3210049
03/26/09
DS51812B-page 24
© 2009 Microchip Technology Inc.