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 Design? ................................................................................. 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 Started ............................................................................................. 15
Appendix A. Schematic and Layouts
A.1 Introduction .................................................................................................. 19
A.2 Board – Schematic ....................................................................................... 20
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 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 online help.
Select the Help menu, and then Topics to open a list of available online help files.
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 Reference Design as a development tool to evaluate the MCP1640 device’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 documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Represents
Examples
Arial font:
Italic characters
Initial caps
Quotes
Underlined, italic text with
right angle bracket
Bold characters
N‘Rnnnn
Text in angle brackets < >
Courier New font:
Plain Courier New
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
Represents code supplied by
user
DS51999A-page 6
File>Save
Press <Enter>, <F1>
#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}
var_name [,
var_name...]
void main (void)
{ ...
}
© 2011 Microchip Technology Inc.
Preface
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 Boost Regulator
with True Output Disconnect or Input/Output Bypass Option” (DS22234)
THE MICROCHIP WEB SITE
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CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
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•
•
•
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Field Application Engineer (FAE)
Technical Support
Customers should contact their distributor, representative or field application engineer
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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.
DS51999A-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
INPUT BOOST CONVERTER
REFERENCE DESIGN
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.
TABLE 1-1:
PART NUMBER SELECTION
PWM/PFM
Mode
PWM
Mode
True Output
Disconnect
Shutdown
Option
Input to Output
Bypass
Shutdown
Option
MCP1640
X
—
X
—
MCP1640B
—
X
X
—
MCP1640C
X
—
—
X
MCP1640D
—
X
—
X
Part Number
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
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:
- IOUT > 100 mA @ 1.2V VIN, 3.3V VOUT
- IOUT > 350 mA @ 2.4V VIN, 3.3V VOUT
- IOUT > 350 mA @ 3.3V VIN, 5.0V VOUT
• Low Start-up Voltage: 0.65V, typical 3.3V VOUT @ 1 mA
• Low Operating Input Voltage: 0.35V, typical 3.3VOUT @ 1 mA
• Adjustable Output Voltage Range: 2.0V to 5.5V
• Maximum Input Voltage ≤ VOUT < 5.5V
• 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 Bypass Option (MCP1640C/D)
• Shutdown Current (All States): < 1 µA
• Low Noise, Anti-Ringing Control
• Overtemperature Protection
L1
4.7 µH
VIN
1.5V
SW V
OUT
VIN
Alkaline
+
-
FIGURE 1-1:
DS51999A-page 10
CIN
4.7 µF
VOUT
3.3V @ 100 mA
536 KΩ
VFB
EN
COUT
10 µF
309 KΩ
GND
Typical MCP1640 Single Cell Input Boost Converter.
© 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 (RT and RB on Figure 1-2), a lower/higher
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 output, the board is capable of a maximum of 50 mA 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 (VOUT High). At start-up, MCP1640
starts as the current generator for the Output Capacitor (COUT). Because at this time,
the internal N-MOS switch is OFF, a Start-up Resistor (RStart), connected in parallel with
the N-MOS switch, should be used.
LBoost
Two Cells Input
CIN
VOUT High > 6V
N-MOS
Switch
RStart
SW
VIN
RT
COUT
Load
FB
VOUT
RB
EN GND
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 INCLUDE?
The MCP1640 Input Boost Converter kit includes:
• MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design, 102-00386
• Important Information Sheet
© 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.
MCP1640 12V/50 mA TWO CELLS
INPUT BOOST CONVERTER
REFERENCE DESIGN
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
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
80.0
Efficiency (%)
75.0
70.0
65.0
60.0
VIN = 2.4V
55.0
VIN = 3.0V
50.0
50 0
45.0
40.0
10
Maximu
um Load Current (mA)
FIGURE 2-1:
3.0V Input.
20
30
40
Load Current (mA)
50
Efficiency vs. Load Current for 12V Output at 2.4V and
80
70
60
50
40
30
20
10
0
2
2.4
2.8
3.2
3.6
Input Voltage (V)
FIGURE 2-2:
DS51999A-page 14
Maximum Load Current vs. Input Voltage at 12V Output.
© 2011 Microchip Technology Inc.
Installation and Operation
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:
• VIN for positive power
• 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 VOUT and is referenced to GND. The minimum output
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
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:
Set 3.0V
PWR Supply
FIGURE 2-3:
Setup Circuit.
240R/0.5W
1. Connect the power at VIN and GND terminals of the board.
2. Set the power supply to 3.0V.
3. Connect a voltmeter and a 240Ω/0.5W resistor between VOUT and GND
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 (VOUT = 12V).
V-meter
R
MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design
© 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 VOUT pin (this output is unregulated).
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 VIN) and Continuous
mode waveforms (60 mA load at 2.4V VIN, where the inductor peak current is close to
the maximum input peak current limit of the MCP1640 device, 800 mA). Once the
800 mA limit is reached, VOUT value is decreasing (goes out of regulation). The mean
value of the inductor current (IL) is equal for a boost converter with the input current
(except the current consumption of MCP1640).
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 (IL) and Load Current (IOUT)
Waveforms for 60 mA Load and 2.4V Input in Continuous mode.
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 (VOUT).
The two sense resistors, RT and RB, set the output (VOUT) at 12.0V according to the
following equation:
EQUATION 2-1:
V OUT
R T = R B × ⎛ ------------- – 1⎞
⎝ V FB
⎠
Where:
Note:
© 2011 Microchip Technology Inc.
VFB
=
1.21V
VFB
=
Reference voltage of the FB pin
VOUT
=
12.0V
RB
=
Resistor’s value is selected by the designer
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.
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 VFB input
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 VOUT
pin (CL), is charged to a value close to the input voltage. During start-up, the rectifying
switch limits the maximum current. Because at start-up, the external n-channel MOS
(Q) transistor is OFF, a start-up resistor (RS) is bypassing it and the CL cap is supplied.
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, RT and RB, are connected to the high output voltage. The
MCP1640 gets its start-up bias from VIN. Once the output exceeds the input, bias
comes from the output. The CL capacitor is mandatory, because it smooths the output
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 (RL
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 VOUT.
The board works well in Discontinuous mode. However, once entered into Continuous
mode, VOUT goes out of regulation.
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.
Note:
DS51999A-page 18
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.
© 2011 Microchip Technology Inc.
MCP1640 12V/50 mA TWO CELLS
INPUT BOOST CONVERTER
REFERENCE DESIGN
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
© 2011 Microchip Technology Inc.
DS51999A-page 19
MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design
BOARD – SCHEMATIC
MCP1640
VOUT
Notes:
* Do not populate in case of instability,
use 2k or 3k resistors
CIN
10µ
L
4μ7
VIN
2
1
2µ2
10µ
COUT
VOUT
A.2
DS51999A-page 20
© 2011 Microchip Technology Inc.
Schematic and Layouts
A.3
BOARD – TOP SILK AND PADS
© 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.
Schematic and Layouts
A.5
BOARD – BOTTOM COPPER AND PADS
© 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 Materials
TABLE B-1:
Qty
BILL OF MATERIALS (BOM)(1)
Reference
Description
Manufacturer
®
Part Number
1
CIN
CAP. CER 10 µF 6.3V X5R 20% 0603
TDK Corporation
C1608X5R0J106M
1
COUT
CAP. CER 10 µF 16V X5R 0805
TDK Corporation
C2012X5R1C106M
1
CL
CAP. CER 2.2 µF 6.3V X5R 20% 0603
TDK Corporation
C1608X5R0J225M
1
D
SCHOTTKY RECT. 40V 0.5A SOD323
NXP Semiconductors
PMEG4005AEA,115
®
90121-0122
0
J1, J2
DO NOT POPULATE
CONN. HEADER 2POS .100" R/A TIN
Molex
1
L
INDUCTOR POWER 4.7 µH 1.1A SMD
TDK Corporation
1
PCB
RoHS-compliant bare PCB, MCP1640
12V/50 mA Two Cells Input Boost
Converter Reference Design
1
Q
MOSFET N-CH 30V 2.2A SSOT3
Fairchild Semiconductor® FDN337N
1
RE
RES. 1.0M OHM 1/10W 5% 0603 SMD
Panasonic® – ECG
ERJ-3GEYJ105V
YAGEO®
RC0603JR-07300RL
—
VLS3015ET-4R7M
104-00386
1
RS
RES. 300 OHM 1/10W 5% 0603 SMD
0
RL
DO NOT POPULATE
RES. 1.0k OHM 1/10W 5% 0603 SMD
Panasonic – ECG
ERJ-3GEYJ102V
1
RB
RES. 180k OHM 1/10W .5% 0603 SMD
YAGEO
RT0603DRD07180KL
1
RT
RESISTOR 1.60M OHM 1/10W 1% 0603 Panasonic – ECG
1
U1
MCP1640 PWM Synchronous Boost
Converter – SOT23-6
Microchip Technology Inc. MCP1640BT-I/CHY
4
VIN, VOUT,
GND(s)
PC TEST POINT TIN SMD
Harwin PLC.
4
Note 1:
—
3M – SJ5382TRANS – FEET, STICK ON, 3M
PK144
ERJ-3EKF1604V
S1751-46R
SJ5382TRANS
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.
© 2011 Microchip Technology Inc.
DS51999A-page 25
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DS51999A-page 26
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08/02/11
© 2011 Microchip Technology Inc.