MCP3907T-I/SS - Microchip Technology

MCP3907

Energy Meter

Reference Design

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Analog-for-the-Digital Age, Application Maestro, CodeGuard,

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ECONOMONIT OR, FanSense , HI-TIDE, In-Circuit Seria l

Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Cert ified

logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code

Generation, PICC, PICC-18, PICDEM, PIC DEM .net, PICkit,

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ISBN:

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Microchip received ISO/TS-16949:2002 certification for its worldwide

headquarters, design and wafer fabrication facilities in Chandler and

Tempe, Arizona; Gresham, Oregon and design centers in California

and India. The Company’s quality system processes and procedures

are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping

devices, Serial EEPROMs, microperiph erals, nonvolatile memory and

analog products. In addition, Microchip’s quality system for the design

and manufacture of development systems is ISO 9001:2000 certified.

Trademarks

The Microchip name and logo, the Microchip logo, dsPIC,

KEELOQ, KEELOQ logo , MPLAB, PIC, PICmicro, PI C START,

PIC32 logo, rfPIC and UNI/O are registered tr ademark s of

Microchip Technology Incorporat ed in the U.S.A. and other

countries.

FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,

MXDEV, MXLAB, SEEVAL and The Embedded Control

Solutions Company are registered trademarks of Microchip

Technology Incorporated in the U.S.A.

Analog-for-the-Digital Age, Application Maestro, CodeGuard,

dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,

ECONOMONIT OR, FanSense , HI-TIDE, In-Circuit Seria l

Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Cert ified

logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code

Generation, PICC, PICC-18, PICDEM, PIC DEM .net, PICkit,

PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance,

TSHARC, UniWinDriver, WiperLock and ZENA are

trademarks of Microchip Technology Incorporat ed in the

U.S.A. and other countries.

SQTP is a service mark of Microchip T echnology Incorporated

in the U.S.A.

All other trademarks mentioned herein are property of their

respective companies.

Printed on recycled paper.

ISBN: 978-1-60932-450-6

Microchip received ISO/TS-16949:2002 certification for its worldwide

headquarters, design and wafer fabrication facilities in Chandler and

Tempe, Arizona; Gresham, Oregon and design centers in California

and India. The Company’s quality system processes and procedures

are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping

devices, Serial EEPROMs, microperiph erals, nonvolatile memory and

analog products. In addition, Microchip’s quality system for the design

and manufacture of development systems is ISO 9001:2000 certified.

MCP3907 ENERGY METER

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 What is the MCP3907 Energy Meter Reference Design? ..............................9

1.3 What the M CP3907 Energy Meter Reference Design Kit Includes ................9

Chapter 2. Installation and Operation

2.1 Introduction ...................................................................................................11

2.2 Fea tures ....... ....... ....... ...... ....... ....... ...... .. ....... ....... ...... ....... ....... ...... ....... ...... . 12

2.3 Ge tting St a rt ed .. .. ....... ...... ....... ....... ...... ....... ...... ....... ....... .. ....... ...... ....... ...... . 12

2.4 MCP3907 Energy Meter Reference Design Overview ...... ...........................13

2.5 Fr o n t si d e of th e P CB – D e ta il e d De scrip t io n ........... ........... ....... ...... ....... ..... 15

2.6 Bac k S id e of the P C B – D e ta il e d Des c rip tion ........... ....... ...... ....... .. ....... ...... . 16

Appendix A. Schema tic and Layouts

A.1 Introduction ..................................................................................................17

A.2 Schematics and PCB Layout ........................... .................. .. .. .................. .. ..17

A.3 Bo a rd – Sc h ematic ....... ....... ...... ....... ...... ... ...... ....... ....... ...... ....... ...... ....... ..... 18

A.4 Board – Top Silk and Pads ..........................................................................19

A.5 Bo a rd – T o p La y er ....... ....... ...... ....... ...... ....... ....... ...... ....... ....... ...... ....... ...... . 19

A.6 Board – Bottom Silk and Pads .......... ...........................................................20

A.7 Bo a rd – Bo ttom La y e r ......... ...... .. ....... ....... ...... ....... ....... ...... ....... ...... ....... ..... 20

Appendix B. Bill of Materials (BOM)

Worldwide Sales and Service ....................................................................................24

MCP3907 Energ y Meter Reference De sign

NOTES:

MCP3907 ENERGY METER

REFERENCE DESIGN

Preface

INTRODUCTION

This chapter contains general information that will be useful to know before using the

MCP3907 Energy Meter Reference Design. Items discussed in this chapter include:

• Document Lay out

• Conventions Used in this Guide

• Recommended Reading

• The Microchip Web Site

• Customer Support

• Document Rev isio n Histor y

DOCUMENT LAYOUT

This document describes how to use the MCP3907 Energy Meter Reference Design

as a development tool to emulate and debug firmware on a target board. The manual

layout is as follows:

•Chapter 1. “Product Overview” – Important information about the MCP3907

Energy Meter Reference Design.

•Chapter 2. “Installati on and Operation” – Includes instructions on how to get

started with this board, with a detailed description of each block.

•Appendix A. “Schematic and Layouts” – Shows the schematic and layout

diagrams for the MCP3907 Energy Meter Reference Design.

•Appendix B. “Bill of Materials (BOM)” – Lists the part s used to build the

MCP3907 Energy Meter Reference Design.

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 th e

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.

MCP3907 Energ y Meter Reference De sign

CONVENTIONS USED IN THIS GUIDE

This manu al us es the followi ng docum entatio n conv en tion s:

DOCUMENTATION CONVENTIONS

Description Represents Examples

Arial font:

Italic characters Referenced books MPLAB® IDE User’s Guide

Emphasized text ...is the only compile r...

Initial caps A window the Output window

A dialog the Settings dialog

A menu selection select Enable Programmer

Quotes A field name in a window or

dialog “Save project before build”

Underlined, italic text with

right angle bracket A menu path File>Save

Bold characters A dialog button Click OK

A tab Click the Power tab

N‘Rnnnn A number in verilo g forma t,

where N is the tota l number of

digit s, R is th e radi x and n is a

digit.

4‘b0010, 2‘hF1

Text i n angl e brackets < > A key on the keybo ard Press <Ent er> , <F1>

Courier New font:

Plain Courie r New Sample source code #define START

Filenames autoexec.bat

File paths c:\mcc18\h

Keywords _asm, _endasm, static

Command-line options -Opa+, -Opa-

Bit values 0, 1

Constants 0xFF, ‘A’

Italic Courier New A variable argument file.o, where file ca n be

any val id filena me

Square brackets [ ] Optional arguments mcc18 [options] file

[options]

Curly brackets and pipe

character: { | } Choice of mutually exclusive

arguments; an OR selection errorlevel {0|1}

Ellipses... Replaces repeated text var_name [,

var_name...]

Represents code supplied by

user void main (void)

{ ...

}

Preface

RECOMMENDED READING

This user's guide describes how to use MCP3907 Energy Meter Reference Design.

Other useful documents are listed below . The following Microchip documents are avail-

able and recommended as supplemental reference resources.

MCP3905A/05L/06A Data Sheet – “Energy Metering ICs with Active Real Power

Pulse Output” (DS22011)

MCP3907 Data Sheet – “Prec ision Energy Mete ring IC with Active Power Output,

SPI Interface and Internal Oscillator” (DS22256)

MCP3909 Dat a Sheet – “Energy Metering IC with SPI Interface and Active Power

Pulse Output”(DS22025)

This data sheet provides detailed information regarding the MCP3907 device.

AN994 – “IEC Compliant Active Energy Meter Design using the MCP3905A/06A”

(DS00994)

This application note documents the design decisions associated with MCP3907

Energy Meter Reference Design. The design decisions for the MCP3905A/06A and

MCP3909 are applicable to the MCP3907 device.

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 rele ases, 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.

DOCUMENT REVISION HISTORY

Revision A (August 2010)

• Initial Release of this Document.

MCP3907 Energ y Meter Reference De sign

NOTES:

MCP3907 ENERGY METER

REFERENCE DESIGN

Chapter 1. Product Overview

1.1 INTRODUCTION

This chapter provides an overview of the MCP3907 Energy Meter Reference Design

and covers the following topics:

• What is the MCP3907 Energy Meter Reference Design?

• What the MCP3907 Energy Meter Reference Design Kit Includes

1.2 WHAT IS THE MCP3 907 ENERGY METE R REFERENCE DESIGN?

The MCP3907 Energy Meter Reference Design is a device energy metering IC that

supplies real power information via a pulse output. The MCP3907 Energy Meter Ref-

erence Design device includes an internal oscillator for low cost meter designs. An

external 3.58 MHz crystal is not required.

The MCP3907 Energy Meter Reference Design is used as a reference design for single

phase residential meters. The MCP3907 Energy Meter Reference Design includes all

the necessary PCB circuits and PCB layout tips required for IEC energy meter

compliance.

1.3 WHAT THE MCP3907 ENERGY METER REFERENCE DESIGN KIT INCLUDES

This MCP3907 Energy Meter Reference Design kit includes:

• MCP3907 Energy Meter Reference Design, 102-00129

• Important Informati on She et

MCP3907 Energ y Meter Reference De sign

NOTES:

MCP3907 ENERGY METER

REFERENCE DESIGN

Chapter 2. Installation and Operation

2.1 INTRODUCTION

The MCP3907 Energy Meter Reference Design is a complete stand-alone

single-phase residential meter design for energy meter manufacturers. This energy

meter design does not require a crystal for a lower cost meter design. This design also

serves as the design of the analog front end (AFE) for advanced meter products. The

design includes a low cost DC power supply circuit and the necessary protection for

IEC62053-21 EMC testing and IEC62053-21 accuracy.

FIGURE 2-1: MCP3907 Stand-Alone Energy Meter and Microcontroller-Based Energy-Using

MCP3907 AFE Design.

For more detailed information regarding design decisions and approach to IEC

compliance using the circuitry in this board, please refer to AN994 application note

(DS00994).

current sensing

element

1000 imp/KWh

Class 1 Meter

5(40)a

current sensing

element

Class 1 Met er 5(40)a

POWER = 1432 kW

ENERGY = 43213 kWh

01/05/2010

15:23:23

ANALOG

DIGITAL

PIC

MCU

MCP3907 Stand-Alone Mechanical Counter

Energy Meter Micro contr oll er- based LCD Energy Meter

MCP3907

Reference Design

MCP3907

MCP3907 Energ y Meter Reference De sign

2.2 FEATURES

The MCP3907 Energy Meter Reference Design has the following features:

• Protection for IEC62053-21 Energy Meter EMC Immunity Tests

• On-board DC power supply

• Resistor divider circuit for single-point meter calibration

• Connections for current sensing shunt or other current sensing element

• Connection for voltage sensing and power supply biasing

• Connec tio ns for mechan ic al co unte r and ca li brati on outpu t

• Low noise PCB layout for small signal conversion, and IEC accuracy compliance

for small sh unt val ue s

• Low cost design

2.3 GETTING STARTED

The MCP3907 Energy Meter Reference Design is a complete stand-alone energy

meter compliant to IEC62053-21, IEC1036 and other legacy IEC energy meter

specifications. This meter can be manufactured by performing the two steps detailed in

this document. For the external connections, the following terms are used:

• “Phase” – refers to the hot or line side of the power supply lines

• “Neutral” – refers to the return wire or low side of the power supply lines

2.3.1 S tep 1: External Connections

Connections are made to the phase and neutral wire for voltage detection and AC/DC

power supply . The MCP3907 Energy Meter Reference Design is designed to be biased

to the phase or hot side of a 2-wire power supply system.

Step 1a – Connect JP4 to the phase power supply line connection

Step 1b – Connect JP3 to the neutral line

Step 1c – Connect JP1 and JP2 across the shunt

Step 1d – Connect JP5 and JP6 to the mechanical counter

Installation and Op eration

2.3.2 S tep 2: Calibration of the Frequency Output Using the Voltage

Divider Calibr ation Circuit

Each meter must be calibrated using the voltage divider circuit going into channel 1 of

the MCP3907 device. A known power is supplied to the meter (e.g 1000W), aiming the

output frequency of 1000 imp/kWh as a goal. The resistor divider is then successively

lowered until the output frequency is matched. For more detailed information regarding

meter calibration and the PCB design approach used with the circuitry described in this

document, please refer to AN994 application note.

FIGURE 2-2: Picture of Complete Stand-Alone MCP3907 Energy Meter

Reference Design.

2.4 MCP3907 ENER GY METER REFERENCE DESIGN OVERVIEW

This reference design can be used as either a complete stand-alone mechanical

counter energy meter, or as the analog front-end design in advanced microcontroller

based meter designs.

The analog front-end (AFE) design limits the overall meter accuracy. A low-noise,

proven AFE circuit and layout is still required for a high accuracy meter . For both meter

types the current sense input, voltage sense input, calibration scheme, jumper

selection and power supply, the design blocks described here should apply.

This design keeps all of the major components on the back side of the PCB. This

minimizes any environmental side effect when a meter case experiences failure. Only

the necessary components for calibration, jumper selection and external connections

are placed on the front side of the board. Keeping the larger DC power supply compo-

nents on the back side of the board is also necessary, for installation in some meter

cases with PCB stand-offs.

MCP3907 Energ y Meter Reference De sign

The major components on the front side of the MCP3907 Energy Meter Reference

Design are listed below this paragraph. See descriptions in Section 2.5 “Front side of

the PCB – Detailed Description”:

• Shunts for Gain and FC selection (J11–J15)

• Calibration Jumpers (J1–J10)

• Output Connections for Mechanical Counter and Calibration (JP5-JP7)

• Connection to Current Sensing Element (JP1, JP2)

• Connection to Voltage or Phase Line and Ground Reference Point (JP3, JP4)

The major components on the back side of the MCP3907 Energy Meter Reference

Design are listed below. See descriptions in Section 2.6 “Back Side of the PCB –

Detaile d Description”.

• MCP3907 Device (U1)

• DC Power Supply (C17, C16, U2, C18, D2)

• Metal Oxide Varistor (MOV1)

• Optical Isolator(U3)

• The Analog Ground Plane, Power Supply Ground Plane, Moat

The following two sections give an overview of the blocks and their functionality. For

more detailed information regarding design decisions and approach to IEC1036

compliance please refer to AN994 application note – “IEC Compliant Active Energy

Meter Design using the MCP3905A/06A”. For a more detailed circuit schematic, refer

to Appendix A. “Schematic and Layouts” and Appendix B. “Bill of Materials

(BOM)”.

FIGURE 2-3: MCP3907 Energy Meter Reference Design Block Diagram.

Calibration

Jumpers (J1-J10)

Shun t s for Gain,

FC and HPF selection

(J11-J15)

Output Conn.

Current Conn .

(JP1,JP2)

FRONT

Power Supply

Ground Plan e

Analog

Ground Plane

Power Supply

Ground Plane

Analog

Ground Plan e

BACK

DC Power

Supply

MCP3907 (U1)

Opto.

Isolator (U3)

MOV1

(JP5-JP7)

Installation and Op eration

2.5 FRONT SIDE OF THE PCB – DETAILED DESCRIPTION

2.5.1 Shunts for Gain and FC selection (J11–J15)

Positions for both logic “high” and logic “low” are here for all gains and frequency con-

stant selections. The logic “high” positions are labeled J1H, and the “low” positions are

labeled J1L, as an example for Jumper 1. Do not short both the “high” and the “low”

positions for any of the jumpers.

2.5.2 Calibration Jumpers (J1–J10)

Calibration resistors for each of these jumper locations are located directly beneath the

associated jumper. When a shorting resistor or a jumper is in place, the associated

calibr ati on resi stor is shorte n ed and bypasse d.

2.5.3 Output Connections for Mechanical Counter and Calibration

(JP5-JP7)

JP5 and JP6 are the differential output drive for the mechanical counter.

JP7 is the calibration or microcontroller output that is connected to HFOUT on the

MCP3907 devices. An LED is supplied to assist in any optical calibration schemes.

2.5.4 Connection to Current Sensing Element (JP1, JP2)

These two connections lead directly through LRC filtering into Channel 0 of the

MCP3907 device. The schematic in Appendix A. “Schematic and Layouts” use s a

low cost shunt as current sensing element. The shunt resistance should be placed in

parallel with these two connections, between JP1 and JP2.

2.5.5 Connection to Voltage or Phase Line and Ground Reference

Point (JP3, JP4)

These two connections feed the DC power supply circuitry described in

Section 2.6.2 “DC Power Supply (C17, C16, U2, C18, D2)”. JP4 is connected to the

ground of the PCB, and JP3 to the high side of the DC power supply circuitry. JP3 is

also connected to the resistor divider that feeds the analog input of Channel 1 of the

MCP3907 device. This is the measuring voltage channel, connected to the differential

input in a single-ended fashion. See Section A.3 “Board – Schematic” for further

details.

MCP3907 Energ y Meter Reference De sign

2.6 BACK SIDE OF THE PCB – DETAILED DESCRIPTION

2.6.1 MCP3907 Device (U1)

The MCP3907 device is located on the right hand side of the back side of the board,

where the analog ground plane exists. The MCP3907 device has appropriate bypass

capacitors on VDD coming from the DC power supply circuitry. The MCP3907 device

has all its input logic pins connected to user selectable jumpers, with one exception,

the HPF pin. For this system the HPF is turned on with this pin connected to VDD; the

device is in AC mode only. The REVP connection is not connected in this reference

design, and this pin should be left floating. The other three output pins (FOUT0, FOUT1,

HFOUT) are connected to nodes JP5, JP6 and JP7, described in this document.

2.6.2 DC Power Supply (C17, C16, U2, C18, D2)

The DC power supply is created from a half-wave Zener diode-limited AC signal,

feeding a 7805 +5V regulator. C17 and C16 divide the AC signal coming directly from

the line (designed in this document for 220V), and Zener diode D2 limits the peak

voltage to 15V. For more information regarding this power supply design see

application note AN994 – “IEC Compliant Active Energy Meter Design using the

MCP3905A/06A” (DS00994).

2.6.3 Metal Oxide Varistor (MOV1)

A Metal Oxide Varistor (MOV) is included in this design to suppress any high voltage

transients coming through the power lines.

2.6.4 Optical Isolator(U3)

An optical isolator is included in the MCP3907 Energy Meter Reference Design as an

additional level of protection for other circuitry used in advanced meter designs (PIC®

microcontroller, DSP or otherwise). It is connected to the HFOUT frequency output of

the MCP3907 device. Depending on the meter design, this optical isolator may not be

required. This design is a direct-connect meter that has the entire PCB referenced to

the line side of the power supply, therefore any other circuitry would either need to be

biased to the same point or isolated using this scheme. A pull-up resistor is required on

the output of the optical isolator to allow the HF logic signal to appear.

2.6.5 The Analog Ground Plane, Power Supply Ground Plane, Moat

The MCP3907 energy meter reference design PCB is designed for low-noise

performance and immunity to external influences, as required by IEC62053-21 and

legacy IEC energy meter specifications, such as IEC61036. The DC power supply and

digital outputs are connected to the power supply ground plane (front side, on the right

of the board). The lower noise analog ground plane, including the MCP3907

connections, is on the opposite side of the board, separated by a moat between the two

ground planes. An inductive choke connects the two grounds. For further information

regarding low-noise PCB design for IEC compliance, see AN994 – “IEC Compliant

Active Energy Meter Design using the MCP3905A/06A”.

MCP3907 ENERGY METER

REFERENCE DESIGN

Appendix A. Schematic and Layouts

A.1 INTRODUCTION

This appendix contains the following schematics and layouts for the MCP3907 Energy

Meter Reference Design:

• Board – Schematic

• Board – Top Silk and Pads

• Board – Top Layer

• Board – Bottom Silk and Pads

• Board – Bottom Layer

A.2 SCHEMATICS AND PCB LAYOUT

The layer order is shown in Figure A-1.

FIGURE A-1: Layer Order.

Top Layer

Bottom Layer

MCP3907 Energ y Meter Reference De sign

A.3 BOARD – SCHEMATIC

Schematic and Layou ts

A.4 BOARD – TOP SILK AND P ADS

A.5 BOARD – TOP LAYER

MCP3907 Energ y Meter Reference De sign

A.6 BOARD – BOTTOM SILK AND PADS

A.7 BOARD – BOTTOM LAYER

MCP3907 ENERGY METER

REFERENCE DESIGN

Appendix B. Bill of Materials (BOM)

TABLE B-1: BILL OF MATERIALS (BOM)

Qty Reference Description Manufacturer Part Number

4 C1, C2, C3, C4 CAP 33000PF 50V CERM X7R 0805 Panasonic® – ECG ECJ-2VB1H333K

2 C5, C13 CAPACITOR TANT 10UF 6.3V 20% SMD Kemet® Electronics

Corp. T491A106M006AS

6 C6, C7, C10,

C12, C14, C15 CAP .1UF 16V CERAMIC X7R 0805 Panasonic – ECG ECJ-2VB1C104K

2 C8, C9 CAP 22PF 50V CERAMIC 0402 SMD Panasonic – ECG ECJ-0EC1H220J

1 C11 CAP 220UF 10V ELECT FC RADIAL Panasonic – ECG EEU-FC1A221S

1 C16 01UF INTERFERFE NCE METAL CAP Panasonic – ECG ECQ-U2A103M N

1 C17 47UF/630VDC METAL POLY CAP Panasonic – ECG ECQ-E6474KF

1 C18 CAP 470UF 35V ELECT FC RADIAL Panasonic – ECG EEU-FC1V471

1 D1 LED GREEN DIFFUSED ROUND LONG Panasonic – SSG LN31GPH

1 D2 RECTIFIER GPP 400V 1A DO-41 Diodes Inc 1N4004-T

1 D3 DIODE ZENER 15V 1W 5% DO-41 Diodes Inc 1N4744A-T

10 J1-J10 RES .1 OHM 1/4W 5% 1210 SMD Panasonic – ECG ERJ-14RSJR10U

6J11H, J12H,

J13H, J14H,

J15H, R24

RES 0.0 OHM 1/8W 5% 0805 SMD Panasonic – ECG ERJ-6GEY0R00V

5 J1 1L, J12L, J13L,

J14L, J15L DO NOT POPULATE — —

8 JP1–JP8 PIN RECPT .032/.046 DIA 0328 SER Mill-Max®

Manufacturing Corp. 0328-0-15-15-34-27-

10-0

1 MOV1 Suppresso r s; Clam pi ng Voltage Max. :710 V EPCOS SIOV-S2 0K2 75

1 PCB RoHS Compliant Bare PCB, MCP3907

Energy Meter Reference Design — 104-00129

3 R1, R2, R13 RES 1.2K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ122X

4 R3, R4, R17, R23 RES 1.00K OHM 1/8W 1% 1206 SMD Panasonic – ECG ERJ-8ENF1001V

1 R5 RES 300K OHM 1/2W 5% 2010 SMD Panasonic – ECG ERJ-12ZYJ304U

1 R6 RES 150K OHM 1/4W 5% 1210 SMD Panasonic – ECG ERJ-14YJ154U

1 R7 RES 75K OHM 1/4W 5% 1206 SMD Panasonic – ECG ERJ-8GEYJ753V

1 R8 RES 39K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ393X

1 R9 RES 18K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ183X

1 R10 RES 9.1K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ912X

1 R11 RES 5.1K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ512X

1 R12 RES 2.2K OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ222X

1 R14 RES 560 OHM 1/16W 5% 0402 SMD Panasonic – ECG ERJ-2GEJ561X

2 R15, R16 RES 330K OHM 1/2W 5% 2010 SMD Panasonic – ECG ERJ-12ZYJ334U

1 R18 RES 820 OHM 1/4W 5% 1206 SMD Panasonic – ECG ERJ-8GEYJ821V

2 R19, R20 RES 20 OHM 1/4W 5% 1206 SMD Panasonic – ECG ERJ-8GEYJ200V

Note 1: The componen t s liste d in t his Bi ll of M ateria ls are re presen tati ve of the PC B assem bly. The relea sed BOM

used in manufacturing uses all RoHS-compliant components.

MCP3907 Energ y Meter Reference De sign

1 R21 RES 470 OHM 1W 5% METAL OXIDE Panasonic – ECG ERG-1SJ471

1 R22 RES 10 OHM 1/4W 5% 1206 SMD Panasonic – ECG ERJ-8GEYJ100V

1 R25 RES 4.7K OHM 1/16W 5% 0805 SMD Panasonic – ECG ERJ-2GEJ222X

1 U1 Energy Metering Devi ce Microchi p

Technology Inc. MCP3907

1 U2 IC VOLT REG 5V 100MA 8-SOIC National

Semiconductor®LM78L05ACM

1 U3 1 CHANNEL OPTO COUPLER TRANS DIP NEC PS2501-1

1 Y1 CRYSTAL 3.579545MHZ 17PF HC49/US ECS Inc ECS-35-17-4

2 Z1,Z2 BEAD CORE SINGLE 3.5X9MM AXIAL Panasonic – ECG EXC-ELSA39

2 Z3,Z4 FERRITE 300MA 150 OHM 1806 SMD Steward LI1806C151R -10

TABLE B-1: BILL OF MATERIALS (BOM) (CONTINUED)

Qty Reference Description Manufacturer Part Number

Note 1: The componen t s liste d in t his Bi ll of Materia ls are repres ent ative of the PCB ass embly. The relea sed BO M

used in manufacturing uses all RoHS-compliant components.

NOTES:

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07/15/10