MCP1650 Multiple
White LED Demo Board
User’s Guide
© 2005 Microchip Technology Inc.
DS51586A
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DS51586A-page ii
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Table of Contents
Preface ........................................................................................................................... 1
Chapter 1. Product Overview
1.1 Introduction ..................................................................................................... 5
1.2 What is the MCP1650 Multiple White LED Demo Board? .............................. 6
1.3 What the MCP1650 Multiple White LED Demo Board 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 Assembly ................................................................................ 15
A.4 Board – Top Metal Layer .......................................................................... 15
A.5 Board – Bottom Metal Layer ...................................................................... 16
Appendix B. Bill Of Materials (BOM)
Appendix C. Demo Board Firmware
C.1 Device Firmware .......................................................................................... 19
Worldwide Sales and Service .................................................................................... 20
© 2005 Microchip Technology Inc.
DS51586A-page iii
MCP1650 Multiple White LED Demo Board User’s Guide
NOTES:
DS51586A-page iv
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO 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 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
MCP1650 Multiple White LED Demo Board. 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 MCP1650 Multiple White LED Demo Board.
The manual layout is as follows:
• Chapter 1. “Product Overview” – Important information about the MCP1650
Multiple White LED Demo Board.
• Chapter 2. “Installation and Operation” – Includes a detailed description of
each function, as well as instructions on how to get started with this board.
• Appendix A. “Schematic and Layouts” – Shows the schematic and layout
diagrams for the MCP1650 Multiple White LED Demo Board.
• Appendix B. “Bill Of Materials (BOM)” – Lists the parts to build the MCP1650
Multiple White LED Demo Board.
• Appendix C. “Demo Board Firmware” – Provides information about the
application firmware and where the source code can be obtained.
© 2005 Microchip Technology Inc.
DS51586A-page 1
MCP1650 Multiple White LED Demo Board User’s Guide
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Arial font:
Italic characters
Initial caps
Quotes
Underlined, italic text with
right angle bracket
Bold characters
‘bnnnn
Text in angle brackets < >
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0xnnnn
Square brackets [ ]
Curly brackets and pipe
character: { | }
Ellipses...
Represents
Examples
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A window
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A field name in a window or
dialog
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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 binary number where n is a
digit
A key on the keyboard
Click OK
Click the Power tab
‘b00100, ‘b10
File>Save
Press <Enter>, <F1>
Sample source code
Filenames
File paths
Keywords
Command-line options
Bit values
A variable argument
#define START
autoexec.bat
c:\mcc18\h
_asm, _endasm, static
-Opa+, -Opa0, 1
file.o, where file can be
any valid filename
A hexadecimal number where 0xFFFF, 0x007A
n is a hexadecimal digit
Optional arguments
mcc18 [options] file
[options]
Choice of mutually exclusive errorlevel {0|1}
arguments; an OR selection
Replaces repeated text
var_name [,
var_name...]
Represents code supplied by void main (void)
user
{ ...
}
RECOMMENDED READING
This user's guide describes how to use MCP1650 Multiple White LED Demo Board.
The following Microchip documents are available and recommended as supplemental
reference resources.
MCP1650 Data Sheet, “750 kHz Boost Controller” (DS21876)
This data sheet provides detailed information regarding the MCP1650 product family.
DS51586A-page 2
© 2005 Microchip Technology Inc.
Preface
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
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CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
•
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Development Systems Information Line
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
DOCUMENT REVISION HISTORY
Revision A (November 2005)
• Initial Release of this Document.
© 2005 Microchip Technology Inc.
DS51586A-page 3
MCP1650 Multiple White LED Demo Board User’s Guide
NOTES:
DS51586A-page 4
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Chapter 1. Product Overview
1.1
INTRODUCTION
The number of applications that utilize white LEDs has steadily increased due to the
extended usage of Liquid Crystal Displays (LCDs) in automotive and cellular telephone
displays, PDAs, handheld electronic games and computer monitors. In order to view
the information on these displays, a light source is needed. Typically, this light source
has been provided by Cold Cathode Flourescent Tubes (CCFT). New product designs
are using White or Blue LEDs as the backlighting source. The MCP1650 is an excellent
choice for driving nine white LEDs with an efficiency of 80%. The peak intensity is set
by the feedback (FB) to the MCP1650. Dimming is accomplished by pulse-width
modulating the shutdown pin of the device.
This chapter covers the following topics:
• What is the MCP1650 Multiple White LED Demo Board?
• What the MCP1650 Multiple White LED Demo Board Kit includes?
Input Voltage:
2.7V - 4.5V supplied by
3 Alkaline Batteries
Boost Power Train
including MCP1650
On/Off and Dimming
Features provided by
PIC10F202
Momentary Switch
FIGURE 1-1:
© 2005 Microchip Technology Inc.
MCP1650 Multiple White LED Demo Board Block Diagram.
DS51586A-page 5
MCP1650 Multiple White LED Demo Board User’s Guide
1.2
WHAT IS THE MCP1650 MULTIPLE WHITE LED DEMO BOARD?
The MCP1650 Multiple White LED Demo Board demonstrates the use of a conventional boost topology in a LED application. The board also serves as a platform to
evaluate the MCP1650 boost controller.
Since designers are tasked with improving efficiency, lowering cost and decreasing
size, white LEDs are now being used. Powering white LEDs, which have a forward drop
(VF) of 3.6V, typically becomes more difficult when the application requires multiple
LEDs. It also requires the output current to be maintained constant with the degrading
battery life and temperature variation. In the MCP1650 Multiple White LED Demo
Board, a solution using the MCP1650 is discussed and shown to be greater than 80%
efficient and also controls the intensity of the LEDs through the PIC10F microcontroller.
The intensity of the LEDs can be controlled through a momentary switch.
The MCP1650 Multiple White LED Demo Board demonstrates the use of the PIC10F
microcontroller in controlling the intensity of the nine white LEDs connected in series.
The board also serves the purpose of evaluating the MCP1650 device.
The design of the demo board is done with boost controller IC MCP1650, which is
capable of generating an output voltage of over 100V. The MCP1650 family has numerous features that include soft-start operation, peak inductor current monitoring, scalable external MOSFET, a shutdown pin for external control, low battery detect and a
power good output. The MCP1650 can be configured in either, the conventional boost
topology (Figure 1-1), a boot-strapped boost topology or a SEPIC topology. The output
voltage of the boost converter is determined by the number of LEDs being driven and
accordingly, the external MOSFET, Schottky diode and the output capacitor need to be
selected.
The feedback voltage (VFB) for the MCP1650 is 1.22V. This is only 4% of the total output voltage when powering nine white LEDs. When the voltage developed across the
sense resistor (RSENSE) is below the internal reference voltage, the internal oscillator
is gated on and the external N-channel MOSFET is pulsed on and off to transfer energy
from the source to the load. This continues until the voltage across RSENSE is above
the 1.22V threshold, gating off the internal oscillator.
1.3
WHAT THE MCP1650 MULTIPLE WHITE LED DEMO BOARD KIT INCLUDES
This MCP1650 Multiple White LED Demo Board kit includes:
• MCP1650 Multiple White LED Demo Board
• MCP1650 Multiple White LED Demo Board User’s Guide
DS51586A-page 6
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Chapter 2. Installation and Operation
2.1
INTRODUCTION
The MCP1650 Multiple White LED Demo Board uses the MCP1650 IC to power the
nine white LEDs which are connected in series. A PIC10F202 microcontroller in a
SOT-23 6 pin package is used to provide the PWM signal to the MCP1650. It also
accepts a push button input that allows the user to adjust the white LED's to three
different intensities of 100%, 50% and 25%.
The PIC10F202 microcontroller is programmable, allowing the user to modify or
develop their own firmware routines to further evaluate the MCP1650 in this
application.
2.2
FEATURES
The MCP1650 Multiple White LED Demo Board has the following features:
• Programmed MCP1650 White LED intensity control via the PIC10F202
• Nine white LEDs connected in series
• PIC10F202 is used to generate the PWM signal which controls the intensity of the
LEDs
• Push button selection for three levels of intensity control
• Includes one battery holder for three AA batteries (batteries not included)
© 2005 Microchip Technology Inc.
DS51586A-page 7
MCP1650 Multiple White LED Demo Board User’s Guide
2.3
GETTING STARTED
The MCP1650 Multiple White LED Demo Board comes fully assembled and tested.
The board requires three AA batteries as a power source for the application.
2.3.1
Powering the MCP1650 Multiple White LED Demo Board
Insert three AA batteries into the battery pack provided on the bottom of the board. As
soon as the system powers up, the internal program of the PIC10F202 will initialize and
remain in a low-power Sleep mode (<0.1 µA) until the S1 button is pressed by the user.
The MCP1650 Multiple White LED Demo Board does not need a power switch or power
jumper because of the “Stand-by” or “Sleep” mode of the PIC10F202 microcontroller
and low shutdown current of the MCP1650. Upon entering Sleep mode, the system
requires less than 0.1 µA (typ) of current. So, with three AA batteries used in the application, the system's power requirements in Sleep mode are minimal.
FIGURE 2-1:
DS51586A-page 8
Setup Configuration Diagram.
© 2005 Microchip Technology Inc.
Installation and Operation
2.3.2
Activating Application and Changing the LED Intensity
1. To activate the LEDs, press the push button momentary switch S1. The LEDs
turn on at full intensity level when the push button is pressed, changing intensity
when the push button is pressed again. There are 3 levels of 100%, 50% and
25% LED intensities (plus the “OFF” state). The input is fused for overcurrent
protection. The intensity of the LEDs are controlled via the SHDN input pin of
MCP1650. A pulse width modulated (PWM) signal is generated by the
PIC10F202 and routed to the SHDN pin of the MCP1650. The MCP1650 is
actually pulsed, and the duty cycle of the PWM waveform is varied depending on
the intensity required. The narrow pulses create a low intensity while wider
pulses create a high intensity.
2. The LEDs will be turned off, and the system will enter Sleep mode, when the
LEDs are at 25% intensity state and the push button is pressed. Subsequent
push button presses will cycle the LEDs as described in step1.
2.3.3
Evaluating the Application
The best way to evaluate the MCP1650 Multiple White LED Demo Board is to analyze
the circuit. Measure voltages and currents with a DVM and probe the board with an
oscilloscope.
The firmware program in the PIC10F202 can also be edited to modify the operation of
the application. For example, the subroutine written to generate the different pulse
widths can be changed to suit the needs of various applications with different
intensities.
Typical Example
Let’s consider a practical application for driving nine white LEDs with the MCP1650
using a three-cell Li-Ion input.
Input voltage:
2.7V to 4.5V
Output voltage:
32.4V (9*VF)
Output current:
15 mA
Switching Frequency:
750 kHz
Duty Cycle:
80% for VIN < 3.8V
Duty Cycle:
56% for VIN > 3.8V
RSENSE is determined by the following equation:
VFB
RSENSE = -----------I OUT
2.3.4
Inductor Selection
Since a high boost ratio is needed, the boost regulator will operate in Discontinuous
Current mode. Therefore, the energy going into the inductor every switching cycle must
be greater than the energy needed to supply the load for that switching cycle. The conservative efficiency estimate of 80% was chosen to provide margin so that the boost
regulator will operate in Discontinuous Current mode.
P OUT = VOUT × I OUT
P OUT = 32.4V × 15mA
POUT = 0.486 watts
© 2005 Microchip Technology Inc.
DS51586A-page 9
MCP1650 Multiple White LED Demo Board User’s Guide
POUT
PIN = -----------------------Efficiency
0.486w
PIN = ----------------80%
PIN = 0.608 watts
The equation for the energy flowing into the inductor is given below. The power in the inductor is
equal to the inductor energy times the switching frequency (FSW).
2
1
Energy = --- × L × I PK
2
Power = Energy × FSW
The peak inductor current is:
V IN
I PK = -------- × T ON
L
Using a standard inductor value of 4.7 µH, the power in the inductor is calculated.
TON = (1/FSW) * Duty Cycle
IPK (2.7V) = 0.612A
Energy (2.7V) = 0.880 µ-Joules
Power (2.7V) = 0.66W
There is a second operating point that needs to be addressed when VIN is 3.8V and the
duty cycle is 56%.
TON = (1/FSW) * Duty Cycle
IPK (3.8V) = 0.603A
Energy (3.8V) = 0.854 µ-Joules
Power (3.8V) = 0.640W
For both operating points, the inductor power is close to the necessary maximum input
power, forcing the converter to operate in Continuous Current mode. Therefore, a
4.7 µH inductor is too large and the peak input current needs to be increased. A 3.3 µH
inductor is selected.
TON = (1/FSW) * Duty Cycle
IPK (2.7V) = 0.872A
Energy (2.7V) = 1.256 µ-Joules
Power (2.8V) = 0.942W
IPK (3.8V) = 0.859A
Energy (3.8V) = 1.219 µ-Joules
Power (3.8V) = 0.914W
Now that the inductor energy is greater than the maximum required input energy, the
converter will operate in Discontinuous Current mode.
DS51586A-page 10
© 2005 Microchip Technology Inc.
Installation and Operation
When selecting the MOSFET, a low RDSon logic-level N-channel is recommended.
Since the input voltage ranges from 2.7V to 4.5V, the MOSFET must have a turn-on
voltage as low as 2.7V. Ideally, the MOSFET would have RDSon as low as possible and,
therefore, help increase the overall efficiency of the regulator. However, a lower RDSon
typically results in higher gate charge, leading to slower transition times in the
MOSFET, thereby causing increased switching losses. The MOSFET’s drain-to-source
breakdown voltage must be rated to handle the boost output voltage plus margin. There
is a very limited selection for MOSFET's with a drain to source rating greater than 30V
with a gate-to-source voltage less than 5V. By using a 1:1 coupled inductor for the boost
converter, the MOSFET drain-to-source voltage rating is cut in half.
The boost diode requires very fast turn-on and turn-off characteristics because it
switches at the switching frequency of the converter. Schottky diodes are recommended because they are capable of this switching characteristic and have a low
forward drop. As with the MOSFET, the Schottky diode must be rated to handle the
boost output voltage plus margin.
The input and output capacitor size depends on the respective voltages of the
converter. While low value parts are desired because of cost and size, they typically
result in higher ripple voltages. The capacitors should be chosen to provide an
appropriate ripple voltage for the intended application. Ceramic or low effective series
resistance (ESR) tantalum capacitors are appropriate for most applications.
2.3.5
Firmware
The PIC10F202 comes with preprogrammed firmware to operate the system as
described above. The firmware flow diagram is shown in Appendix C. “Demo Board
Firmware”.
There is an initialization routine at the beginning of the program. The program initially
checks for the key press and goes into Sleep mode if there is no key press. The device
will come out of Sleep mode on pin change. The OPTION register is configured to
wake-up on port pin change.
The GPIO port is configured to set GP0 (PWM to the MCP1650) as an output and GP3
(Push Button) as inputs. There are three different subroutines for the three different
intensities provided. Every time the key is pressed, the variable key buffer is incremented to store the next value of the key and move to the respective subroutine in a
cyclic order.
The effect of key de-bounce is accomplished by providing a delay which checks for the
prerequisite time and recognizes only a valid key press. There is a key press check in
each of the subroutine which recognizes the key press and goes to the next subroutine
for a valid key press.
2.3.5.1
PROGRAMMING
Header J1 is provided for in circuit programming. This is an optional feature since the
demo board comes preprogrammed with firmware to operate the system. The
PIC10F202 can be reprogrammed with the Baseline Flash Microcontroller Programmer
(BFMP).
© 2005 Microchip Technology Inc.
DS51586A-page 11
MCP1650 Multiple White LED Demo Board User’s Guide
NOTES:
DS51586A-page 12
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Appendix A. Schematic and Layouts
A.1
INTRODUCTION
This appendix contains the following schematics and layouts for the MCP1650 Multiple
White LED Demo Board:
•
•
•
•
Board – Schematic
Board – Assembly Drawing
Board – Top Metal Layer
Board – Bottom Metal Layer
© 2005 Microchip Technology Inc.
DS51586A-page 13
MCP1650 Multiple White LED Demo Board User’s Guide
A.2
BOARD – SCHEMATIC
DS51586A-page 14
© 2005 Microchip Technology Inc.
Schematic and Layouts
A.3
BOARD – TOP ASSEMBLY
A.4
BOARD – TOP METAL LAYER
© 2005 Microchip Technology Inc.
DS51586A-page 15
MCP1650 Multiple White LED Demo Board User’s Guide
A.5
BOARD – BOTTOM METAL LAYER
DS51586A-page 16
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Appendix B. Bill Of Materials (BOM)
TABLE B-1:
Qty
BILL OF MATERIALS (BOM)
Reference
Description
Manufacturer
Part Number
1
CIN
CAP 47UF 6.3V CERAMIC X5R 1210
Panasonic - ECG
ECJ-4YB0J476M
1
COUT
CAP CER 1UF 50V X7R 10% 1206
TDK Corporation
C3216X7R1H105K
2
C1, C2
CAP .10UF 50V CERAMIC X7R 1206
Yageo America
CC1206KRX7R9BB104
1
D1
MBRS2040LT3
ON Semiconductors
MBRS2040LT3
1
F1
PolySwitch Resettable Fuses
Raychem® Corp.
MINISMDC110
Molex
1
J1
CONN HEADER 5POS .100 VERT TIN
1
L1
INDUCTOR SHIELD DUAL 3.3UH SMD Coiltronics
DRQ74-3R3
22-03-2051
9
LED1, LED2,
LED3, LED4,
LED5, LED6,
LED7, LED8,
LED9
LED 5mm Blue/Waterclear Lens
LED Shop
OBWC5.5000-A
1
Q1
FDN337N
Fairchild
FDN337N
2
R1, R2
RES 47.5K OHM 1/10W 1% 0805 SMD
Panasonic - ECG
ERJ-6ENF4752V
1
R3
Resistor 1MOhm 1% 0805 Package
Panasonic - ECG
ERJ-6ENF1004V
1
R4
RES 80.6 OHM 1/8W 1% 1206 SMD
Panasonic - ECG
ERJ-8ENF80R6V
1
S1
Momentary Tact Switches
E-Switch Inc
TL3301NF260QG
®
5016
4
TP1, TP2,
TP3, TP4
SMT Test Point
Keystone Electronics
1
U1
PIC10F202 6-pin SOT-23
Microchip Technology Inc PIC10F202T-I/OT
1
U2
MCP1650 8-pin MSOP
Microchip Technology Inc MCP1650S-E/MS
1
VIN
3 AA Plastic Battery Holder
Keystone Electronics®
© 2005 Microchip Technology Inc.
2464
DS51586A-page 17
MCP1650 Multiple White LED Demo Board User’s Guide
NOTES:
DS51586A-page 18
© 2005 Microchip Technology Inc.
MCP1650 MULTIPLE WHITE LED
DEMO BOARD USER’S GUIDE
Appendix C. Demo Board Firmware
C.1
DEVICE FIRMWARE
For the latest version of the MCP1650 Multiple White LED Demo Board firmware, visit
the Microchip web site at www.microchip.com.
START
Initialize GP0 = 1(Output Port),
Set Option Reg for 250 Hz Freq
Present Key = 0, TMR0 = 0
Wake-up Due
to Key Press
Yes
No
GP0 = 0
Sleep
Check for Key Press
Yes
Increment Key Buffer
Set GP0 = 1
Reset TMR0
No
No
If Present Key = 02
If Present Key = 01
Yes
If Present Key = 03
Yes
Start Timer
No
Yes
Start Timer
No
TMR0 d 1Fh
Start Timer
No
If TMR0 d 0Eh
Yes
If TMR0 d 06h
Yes
Set GP0 = 0
Yes
FIGURE C-1:
© 2005 Microchip Technology Inc.
No
Set GP0 = 0
No
Yes
If TMR0 d 1Fh
Firmware Flowchart – Page 1.
DS51586A-page 19
WORLDWIDE SALES AND SERVICE
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Fax: 61-2-9868-6755
India - Bangalore
Tel: 91-80-2229-0061
Fax: 91-80-2229-0062
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
India - New Delhi
Tel: 91-11-5160-8631
Fax: 91-11-5160-8632
Austria - Wels
Tel: 43-7242-2244-399
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
China - Chengdu
Tel: 86-28-8676-6200
Fax: 86-28-8676-6599
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
China - Fuzhou
Tel: 86-591-8750-3506
Fax: 86-591-8750-3521
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Korea - Gumi
Tel: 82-54-473-4301
Fax: 82-54-473-4302
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
Atlanta
Alpharetta, GA
Tel: 770-640-0034
Fax: 770-640-0307
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Kokomo
Kokomo, IN
Tel: 765-864-8360
Fax: 765-864-8387
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
San Jose
Mountain View, CA
Tel: 650-215-1444
Fax: 650-961-0286
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
China - Shunde
Tel: 86-757-2839-5507
Fax: 86-757-2839-5571
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
China - Xian
Tel: 86-29-8833-7250
Fax: 86-29-8833-7256
Malaysia - Penang
Tel: 60-4-646-8870
Fax: 60-4-646-5086
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
Taiwan - Hsin Chu
Tel: 886-3-572-9526
Fax: 886-3-572-6459
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
10/31/05
DS51586A-page 20
© 2005 Microchip Technology Inc.