MCP1726
Evaluation Board
User’s Guide
© 2006 Microchip Technology Inc.
DS51550B
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
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Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
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Information contained in this publication regarding device
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and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
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PRO MATE, PowerSmart, rfPIC and SmartShunt are
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ECONOMONITOR, FanSense, FlexROM, fuzzyLAB,
In-Circuit Serial Programming, ICSP, ICEPIC, Linear Active
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© 2006, Microchip Technology Incorporated, Printed in the
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Printed on recycled paper.
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manufacture of development systems is ISO 9001:2000 certified.
DS51550B-page ii
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION BOARD
USER’S GUIDE
Table of Contents
Preface ........................................................................................................................... 1
Chapter 1. Product Overview ....................................................................................... 5
1.1 Introduction ..................................................................................................... 5
1.2 What is the MCP1726 1A LDO Evaluation Board? ........................................ 6
1.3 What the MCP1726 1A LDO Evaluation Board Kit includes .......................... 6
Chapter 2. Installation and Operation ......................................................................... 7
2.1 Introduction ..................................................................................................... 7
2.2 Features ......................................................................................................... 7
2.3 Getting Started ............................................................................................... 7
2.4 Testing Circuit 1 of the MCP1726 Evaluation Board ...................................... 8
2.5 Testing Circuit 2 of the MCP1726 Evaluation Board .................................... 10
Appendix A. Schematics and Layouts ...................................................................... 13
A.1 Introduction .................................................................................................. 13
A.2 Board Schematic ...................................................................................... 14
A.3 Board - Outline ......................................................................................... 15
A.4 Board - Top Layer
.................................................................................... 16
A.5 Board - Bottom Layer ............................................................................... 17
Appendix B. Bill Of Materials (BOM) ......................................................................... 19
Worldwide Sales and Service .................................................................................... 20
© 2006 Microchip Technology Inc.
DS51550B-page iii
MCP1726 Evaluation Board User’s Guide
NOTES:
DS51550B-page iv
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION
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.
INTRODUCTION
This chapter contains general information that will be useful to know before using the
MCP1726 Evaluation 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 MCP1726 Evaluation Board as a development tool. The manual layout is as follows:
• Chapter 1. “Product Overview” – Important information about the MCP1726
Evaluation Board.
• Chapter 2. “Installation and Operation” – Includes instructions on how to get
started with this evaluation board and a description of the evaluation board
operation.
• Appendix A. “Schematics and Layouts” – Shows the schematic and layout
diagrams for the MCP1726 Evaluation Board.
• Appendix B. “Bill Of Materials (BOM)” – Lists the parts used to build the
MCP1726 Evaluation Board.
© 2006 Microchip Technology Inc.
DS51550B-page 1
MCP1726 Evaluation Board User’s Guide
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Arial font:
Italic characters
Represents
Examples
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
File>Save
Press <Enter>, <F1>
var_name [,
var_name...]
void main (void)
{ ...
}
RECOMMENDED READING
This user's guide describes how to use MCP1726 Evaluation Board. The following
Microchip documents are available and recommended as supplemental reference
resources.
MCP1726 Data Sheet, “1A, Low-Voltage, Low Quiescent Current LDO Regulator”
(DS21936)
This data sheet provides detailed information regarding the MCP1726 product family.
DS51550B-page 2
© 2006 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
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
Development Systems Information Line
Customers should contact their distributor, representative or field application engineer
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 B (August 2006)
• Add disclaimer to Bill of Materials regarding RoHS-Compliant part numbers.
Revision A (April 2005
• Initial Release of this Document.
© 2006 Microchip Technology Inc.
DS51550B-page 3
MCP1726 Evaluation Board User’s Guide
NOTES:
DS51550B-page 4
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION
BOARD USER’S GUIDE
Chapter 1. Product Overview
1.1
INTRODUCTION
The MCP1726 1A LDO Evaluation Board is used to evaluate the Microchip MCP1726
1A, low voltage, low-quiescent current, Low-Dropout (LDO) regulator. This evaluation
board contains two circuits, one for the 8-pin DFN package and one for the 8-pin SOIC
package. Each circuit allows the user to evaluate the adjustable or fixed-voltage
version of the part.
This chapter also covers the following topics:
3
VOUT
VIN
VADJ
SHDN CDELAY
4
GND PWRGD
MCP1726_DFN
TP9
6
JP4
5
2
R8
806Ω
PGND
3
+VIN1
7
+VIN1
PGND
SHDN1
8
C6
0.01 µF
3
C5
R10
10 µF
100 kΩ
1
JP6
PGND
VOUT1
Power Good
VOUT2
Power Good
JP5
R7
499Ω
R6
806Ω
PGND
TP12
TP7
R9
10 kΩ
VIN
TP11
PGND
2
TP8
C4
10 µF
U2
1
TP6
+VIN1
+VIN1
TP5
• What is the MCP1726 1A LDO Evaluation Board?
• What the MCP1726 1A LDO Evaluation Board Kit includes
TP10
1
2
D2
+VIN2
PGND
2
R1
10 kΩ
TP2
C1
4.7 µF
TP3
PGND
SHDN1
U1
1
TP1
+VIN2
3
VIN
VOUT
VIN
VADJ
SHDN CDELAY
4
GND PWRGD
8
6
JP1
5
2
MCP1726_SOIC8
+VIN2
R5
806Ω
PGND
3
+VIN2
7
C3
1000 pF
3
R2
100 kΩ
1
C2
4.7 µF
R3
806Ω
PGND
1
PGND
JP2
JP3
R4
499Ω
TP4
2
D1
FIGURE 1-1:
MCP1726 Evaluation Board Schematic.
© 2006 Microchip Technology Inc.
DS51550B-page 5
MCP1726 Evaluation Board User’s Guide
1.2
WHAT IS THE MCP1726 1A LDO EVALUATION BOARD?
The MCP1726 1A LDO Evaluation Board allows the user to evaluate both the fixed and
adjustable versions of the part in the 8-pin SOIC and 8-lead 3X3 DFN packages. An
on-board potentiometer allows the user to easily set the output voltage of the adjustable
voltage version of the device. Status LEDs indicate when input voltage is applied and
when the Power Good (PWRGD) output is in a high condition (output voltage is in
regulation).
Connection terminals are provided for the input voltage, output voltage, ground, power
good and shutdown.
1.3
WHAT THE MCP1726 1A LDO EVALUATION BOARD KIT INCLUDES
This MCP1726 1A LDO Evaluation Board Kit includes:
• The MCP1726 1A LDO Evaluation Board
• Analog and Interface Products Demonstration Boards CD-ROM (DS21912)
- MCP1726 1A LDO Evaluation Board User’s Guide (DS51550)
DS51550B-page 6
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION
BOARD USER’S GUIDE
Chapter 2. Installation and Operation
2.1
INTRODUCTION
The MCP1726 Evaluation Board demonstrates Microchip’s 1A Low-Quiescent Current,
Low-Dropout (LDO) regulator.The evaluation board contains two independent circuits
that allow the user to evaluate the MCP1726 in the 8-pin SOIC and the 8-pin 3X3 DFN
packages. The evaluation board uses a potentiometer to adjust the output voltage of
the MCP1726 device across its entire output voltage range. The evaluation board also
allows for fixed-output voltage versions of the device to be used by simply connecting
the pins of a jumper connector.
2.2
FEATURES
The MCP1726 Evaluation Board has the following features:
•
•
•
•
•
•
•
•
2.3
Input Voltage Range: 2.3V to 6.0V
Adjustable Output Voltage via a Potentiometer
Output Voltage Shutdown via the SHDN Input
Overcurrent Protection (device feature)
Overtemperature Protection (device feature)
Input Undervoltage Lockout (UVLO) Protection (device feature)
Input Power and Power Good Indication (LED)
Power Good Delay Adjust Capability
GETTING STARTED
The MCP1726 Evaluation Board is fully assembled and tested over its input voltage,
output voltage and output current operating range. This board requires the use of an
external input voltage source (+2.3V to +6.0V) and an external load (electronic or
resistive). The Printed Circuit Board (PCB) design provides cooling for the MCP1726
devices. When the devices are operating with high power dissipation (over 1.0W at
room ambient), additional cooling may be required to keep the devices from going into
overtemperature shutdown.
The MCP1726 Evaluation Board contains two circuits to evaluate; one for the SOIC
package and one for the 3X3 DFN package. These circuits are powered independently
of each other through separate connectors/test points. The circuitry for evaluating the
3X3 DFN package has inputs labeled VIN1 and SHDN1, and outputs labeled PWRGD1
and VOUT1. The circuitry for evaluating the SOIC package has inputs labeled VIN2
and SHDN2, and outputs labeled PWRGD2 and VOUT2. The ground connections for
the board are all common to each other and are labeled as GND. There are a total of
four connection points for ground.
All of the connections to the MCP1726 Evaluation Board are made through
surface-mount test points. These test points can be removed with a soldering iron if you
wish to solder wires directly to the pads that are provided on the board.
© 2006 Microchip Technology Inc.
DS51550B-page 7
MCP1726 Evaluation Board User’s Guide
2.4
TESTING CIRCUIT 1 OF THE MCP1726 EVALUATION BOARD
2.4.1
Power Input and Output Connections
Powering the MCP1726 Evaluation Board
1. Apply the input voltage to test points TP7 (VIN1) and TP8 (GND). Connect the
positive side of the input source (+) to test point TP7 (VIN1). Connect the
negative, or return, side (–) of the input source to the test point TP8 (GND).
These two test points are located on the upper left side of the board. The power
supply input voltage must be in the specified operating range for the board to
operate correctly. The UVLO feature of the MCP1726 prevents the device from
operating when the input voltage is too low (see data sheet for UVLO thresholds).
2. When input voltage is applied and is above the input UVLO threshold, the LDO
output will turn on automatically. The SHDN1 input has been pulled up to VIN1
which turns the device on. The LDO output can be turned off by pulling the
SHDN1 input (TP9) low (short SHDN1 to GND).
3. When input voltage is applied, the red portion of the D2 LED will illuminate. As
long as input voltage is present, the red portion of this LED will be on.
Applying the load to the MCP1726 Evaluation Board
1. To apply a load to VOUT1 of the MCP1726 Evaluation Board, the positive-side
of the load (+) should be connected to test point TP12 (VOUT1). The negative
side of the load (–) should be connected to test point TP10 (GND).
2. The maximum output current of the MCP1726 is 1.0A. If the output load exceeds
this level, the MCP1726 will go into current limit at 1.7A. If, during the overload
condition, the device junction temperature exceeds the overtemperature limit of
150°C, the output of the LDO will turn off and wait for the junction temperature to
cool down before turning the LDO output back on. Circuit 1 of the MCP1726 Evaluation Board evaluates the 3X3 DFN package. When operating at room ambient,
this circuit will go into overtemperature shutdown when the power dissipation in
the device reaches about 2.1W.
2.4.2
Adjusting the Output Voltage of the LDO
The MCP1726 Evaluation Board comes with the output voltage preset to 2.5V. To
adjust the output voltage (VOUT1) of circuit 1, the potentiometer, R10, is used. R10 is
a top-side adjust potentiometer. If the desired output voltage is higher than 2.5V, raise
the input voltage to a level that is higher than your desired output voltage. Use a small
flathead screwdriver to adjust the R10 potentiometer and monitor the VOUT1 (TP12)
voltage. If your desired output voltage is less than 2.5V, the input voltage of the LDO
must be set to a minimum of 2.3V, as this is the minimum input voltage of the LDO. The
output voltage of the LDO can then be adjusted using the R10 potentiometer.
The potentiometer will allow you to adjust the output voltage over the full range of 0.8V
to 5.0V. If you would like to use fixed resistor values to set the output voltage of the
LDO, the potentiometer can be removed and the pads for the potentiometer can be
used to solder your fixed value resistors into the circuit.
DS51550B-page 8
© 2006 Microchip Technology Inc.
Installation and Operation
2.4.3
Power Present and Power Good (PWRGD1) Indication
The MCP1726 Evaluation Board has one dual status LED. The dual LED (D2) contains
a red LED and a green LED. The red portion of the LED illuminates to indicate that input
voltage is present.
The green portion of the LED (D2) is used for power good (PWRGD) indication. During
normal operation, if the LDO output is in regulation, the green portion of D2 is
illuminated to provide indication that power is good. If the output voltage of the LDO
falls below the power good threshold limit (below 92% (typical) of the nominal output
voltage regulation value) for any reason (input voltage too low, overtemperature, output
short circuit), the green portion of the LED will turn off. The green portion of the LED is
driven off of the PWRGD1 output.
The power good output (PWRGD1) can be monitored by connecting to TP11. The
power good output of the MCP1726 device is an open-drain output. On the MCP1726
Evaluation Board, the PWRGD1 output can be pulled up to either the LDO input or
output voltage. This can be done through jumpers JP6 and JP5, respectively. To pull
the PWRGD1 output up to the input voltage of the LDO, populate jumper JP6 (place
one of the black shorting tabs on the jumper) and make sure that jumper JP5 is not
populated. To pull the PWRGD1 output up to the output voltage, populate jumper JP5
and make sure that jumper JP6 is not populated. Upon shipment, the board is
configured to have PWRGD1 pulled up to the input voltage. Because the PWRGD1
output is driving the green portion of the D2 LED, the voltage at the PWRGD1 test point
will be clamped to the forward voltage of the LED. If you want to have the PWRGD1
voltage be pulled all the way up to the input or output voltage, remove the D2 LED.
2.4.4
Power Good Time Delay
The MCP1726 device has a power good time delay feature that allows the user to set
the time delay from when the output voltage is in regulation to when the power good
output (PWRGD) goes high. This feature is implemented by the CDELAY pin on the
device (see data sheet for more details). Circuit 1 of the MCP1726 Evaluation Board is
populated with a 0.01 µF capacitor (C6) for the CDELAY pin capacitor. This gives a
typical delay time of 30 ms.
2.4.5
Input and Output Capacitors
The input and output capacitors (C4 and C5, respectively) for Circuit 1 of the MCP1726
Evaluation Board are populated with 10 µF, 6.3V ceramic capacitors. The pads for
these devices have been constructed in such a manner that 0805, 1206 and 1210 size
surface-mount capacitors can be used. This allows the user to populate the board with
capacitors of various values and voltage ratings that mimic their application.
2.4.6
Testing Fixed-Output Voltage Devices
As stated earlier, the MCP1726 Evaluation Board is designed to handle either the
adjustable or fixed-output voltage version of the device (board comes populated with
the adjustable output voltage version). When testing a fixed-output voltage version of
the device, jumper JP4 should be populated (use the additional black jumper top that
is provided). This will connect pin 7 of U2 to the VOUT1 output (for the fixed-output
voltage devices, pins 7 and 8 of the MCP1726 are both VOUT) which is necessary for
proper operation.
© 2006 Microchip Technology Inc.
DS51550B-page 9
MCP1726 Evaluation Board User’s Guide
2.5
TESTING CIRCUIT 2 OF THE MCP1726 EVALUATION BOARD
2.5.1
Power Input and Output Connections
Powering the MCP1726 Evaluation Board
Apply the input voltage to test points TP1 (VIN2) and TP2 (GND). Connect the
positive-side of the input source (+) to test point TP1 (VIN2). Connect the negative, or
return, side (–) of the input source to the test point TP2 (GND). These two test points
are located on the lower-left side of the board. The power supply input voltage must be
in the specified operating range for the board to operate correctly. The UVLO feature
of the MCP1726 prevents the device from operating when the input voltage is too low
(see data sheet for UVLO thresholds).
When input voltage is applied and is above the input UVLO threshold, the LDO output
will turn on automatically. The SHDN2 input has been pulled up to VIN2 which turns the
device on. The LDO output can be turned off by pulling the SHDN2 input (TP3) low
(short SHDN2 to GND).
When input voltage is applied, the red portion of the D1 LED will illuminate. As long as
input voltage is present, the red portion of this LED will be on.
Applying the load to the MCP1726 Evaluation Board
To apply a load to VOUT2 of the MCP1726 Evaluation Board, the positive-side of the
load (+) should be connected to test point TP6 (VOUT2). The negative-side of the load
(–) should be connected to test point TP4 (GND).
The maximum output current of the MCP1726 is 1.0A. If the output load exceeds this
level, the MCP1726 will go into current limit at 1.7A. If, during the overload condition,
the device junction temperature exceeds the overtemperature limit of 150°C, the output
of the LDO will turn off and wait for the junction temperature to cool down before turning
the LDO output back on. Circuit 2 of the MCP1726 Evaluation Board evaluates the
SOIC package. When operating at room ambient, this circuit will go into
overtemperature shutdown when the power dissipation in the device reaches about
1.3W.
2.5.2
Adjusting the Output Voltage of the LDO
The MCP1726 Evaluation Board comes with the output voltage preset to 2.5V. To
adjust the output voltage (VOUT2) of circuit 2, the potentiometer (R2) is used. R2 is a
top-side adjust potentiometer. If the desired output voltage is higher than 2.5V, raise the
input voltage to a level that is higher than your desired output voltage. Use a small flat
head screw driver to adjust the R2 potentiometer and monitor the VOUT2 (TP6)
voltage. If your desired output voltage is less than 2.5V, the input voltage of the LDO
must be set to a minimum of 2.3V, as this is the minimum input voltage of the LDO. The
output voltage of the LDO can then be adjusted using the R2 potentiometer.
The potentiometer will allow you to adjust the output voltage over the full range of 0.8V
to 5.0V. If you would like to use fixed resistor values to set the output voltage of the
LDO, the potentiometer can be removed and the pads for the potentiometer can be
used to solder your fixed-value resistors into the circuit.
DS51550B-page 10
© 2006 Microchip Technology Inc.
Installation and Operation
2.5.3
Power Present and Power Good (PWRGD2) Indication
The MCP1726 Evaluation Board has one dual-status LED. The dual LED (D1) contains
a red LED and a green LED. The red portion of the LED illuminates to indicate that input
voltage is present.
The green portion of the LED (D1) is used for power good (PWRGD) indication. During
normal operation, if the LDO output is in regulation, the green portion of D1 is
illuminated to provide indication that power is good. If the output voltage of the LDO
falls below the power good threshold limit (below 92% (typical) of the nominal output
voltage regulation value) for any reason (input voltage too low, overtemperature, output
short circuit), the green portion of the LED will turn off. The green portion of the LED is
driven off of the PWRGD2 output.
The power good output (PWRGD2) can be monitored by connecting to TP5. The power
good output of the MCP1726 device is an open-drain output. On the MCP1726
Evaluation Board, the PWRGD2 output can be pulled up to either the LDO input or
output voltage. This can be accomplished through jumpers JP2 and JP3, respectively.
To pull the PWRGD2 output up to the input voltage of the LDO, populate jumper JP2
(place one of the black shorting tabs on the jumper) and make sure that jumper JP3 is
not populated. To pull the PWRGD2 output up to the output voltage, populate jumper
JP3 and make sure that jumper JP2 is not populated. Upon shipment, the board is
configured to have PWRGD2 pulled up to the input voltage. Because the PWRGD2
output is driving the green portion of the D1 LED, the voltage at the PWRGD2 test point
will be clamped to the forward voltage of the LED. If you want to have the PWRGD2
voltage be pulled all the way up to the input or output voltage, remove the D1 LED.
2.5.4
Power Good Time Delay
The MCP1726 device has a power good time delay feature that allows the user to set
the time delay from when the output voltage is in regulation to when the power good
output (PWRGD) goes high. This feature is implemented by the CDELAY pin on the
device (see data sheet for more details). Circuit 2 of the MCP1726 Evaluation Board is
populated with a 1000 pF capacitor (C3) for the CDELAY pin capacitor. This gives a
typical delay time of 3 ms.
2.5.5
Input and Output Capacitors
The input and output capacitors (C1 and C2, respectively) for Circuit 2 of the MCP1726
Evaluation Board are populated with 4.7μF, 6.3V ceramic capacitors. The pads for
these devices have been constructed in such a manner that 0805, 1206 and 1210 size
surface-mount capacitors can be used. This allows the user to populate the board with
capacitors of various values and voltage ratings that mimic their application.
2.5.6
Testing Fixed-Output Voltage Devices
As stated earlier, the MCP1726 Evaluation Board is designed to handle either the
adjustable or fixed-output voltage version of the device (board comes populated with
the adjustable output voltage version). When testing a fixed-output voltage version of
the device, jumper JP1 should be populated (use the additional black jumper top that
is provided). This will connect pin 7 of U1 to the VOUT2 output (for the fixed-output
voltage devices, pins 7 and 8 of the MCP1726 are both VOUT), which is necessary for
proper operation.
© 2006 Microchip Technology Inc.
DS51550B-page 11
MCP1726 Evaluation Board User’s Guide
NOTES:
DS51550B-page 12
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION
BOARD USER’S GUIDE
Appendix A. Schematics and Layouts
A.1
INTRODUCTION
This appendix contains the following schematics and layouts for the MCP1726
Evaluation Board.
•
•
•
•
Board Schematic
Board Outline
Board – Top Layer
Board – Bottom Layer
© 2006 Microchip Technology Inc.
DS51550B-page 13
MCP1726 Evaluation Board User’s Guide
BOARD SCHEMATIC
DS51550B-page 14
MCP1726_SOIC
MCP1726_DFN
MCP1726 LDO Fixed and Adjustable Output Eval Board
A.2
© 2006 Microchip Technology Inc.
Schematics and Layouts
A.3
BOARD - OUTLINE
© 2006 Microchip Technology Inc.
DS51550B-page 15
MCP1726 Evaluation Board User’s Guide
A.4
BOARD - TOP LAYER
DS51550B-page 16
© 2006 Microchip Technology Inc.
Schematics and Layouts
A.5
BOARD - BOTTOM LAYER
© 2006 Microchip Technology Inc.
DS51550B-page 17
MCP1726 Evaluation Board User’s Guide
NOTES:
DS51550B-page 18
© 2006 Microchip Technology Inc.
MCP1726 EVALUATION
BOARD USER’S GUIDE
Appendix B. Bill Of Materials (BOM)
TABLE B-1:
Qty
4
2
1
2
1
2
6
2
2
4
2
12
1
BILL OF MATERIALS
Reference
C1, C2
C3
C4, C5
C6
D1, D2
JP1, JP2, JP3,
JP4, JP5, JP6
R1, R9
R2, R10
R3, R5, R6, R8
R4, R7
TP1, TP2, TP3,
TP4, TP5, TP6,
TP7, TP8, TP9,
TP10, TP11,
TP12
U1
(BOM)
Description
Jumper Shorting Posts
CAP 4.7UF 6.3V CERAMIC X5R 0805
CAP 1000PF 50V CERAMIC 0603 SMD
CAP 10UF 6.3V CERAMIC X5R 0805
CAP 10000PF 50V CERAMIC 0603 SMD
LED Dual Green/Red Clear SOT-23
Connector Header 2POS .100 VERT TIN
RES 10.0K Ohm 1/16W 1% 0603 SMD
TRIMPOT 100K Ohm 4mm Top Adj SMD
RES 806 Ohm 1/16W 1% 0603 SMD
RES 499 Ohm 1/16W 1% 0603 SMD
SMT Test Point/Connector
Manufacturer
Part Number
Sullens
Panasonic® Corp.
Panasonic Corp.
Panasonic Corp.
Kemet®
Lumex®
Opto/Components
Molex®/Waldom®
STC02SYAN
ECJ-2FB0J475M
ECJ1VB1H102K
ECJ-2FB0J106M
C0603C103K5RACTU
SSL-LX15IGC-RP-TR
Panasonic
Bourns®
Panasonic
Panasonic
Keystone
Electronics®
ERJ-3EKF1002V
3214W-1-104E
ERJ-3EKF8060V
ERJ-3EKF4990V
5016
22-03-2021
1A Low Quiescent Current LDO, AdjustMicrochip
MCP1726-ADJE/SN
able Output, 8-Pin SOIC Package
Techonology Inc.
1
U2
1A Low Quiescent Current LDO, AdjustMicrochip
MCP1726-ADJE/MF
able Output, 3X3 DFN Package
Techonology Inc.
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.
© 2006 Microchip Technology Inc.
DS51550B-page 19
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07/21/06
DS51550B-page 20
© 2006 Microchip Technology Inc.