MCP4725 PICtail Plus Daughter Board User’s Guide © 2008 Microchip Technology Inc.

MCP4725 PICtail Plus Daughter Board User’s Guide © 2008 Microchip Technology Inc.
MCP4725
PICtail Plus Daughter Board
User’s Guide
© 2008 Microchip Technology Inc.
DS51722A
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
mean that we are guaranteeing the product as “unbreakable.”
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
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, Accuron,
dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro,
PICSTART, PRO MATE, rfPIC and SmartShunt are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
FilterLab, Linear Active Thermistor, MXDEV, MXLAB,
SEEVAL, SmartSensor 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,
ECONOMONITOR, FanSense, In-Circuit Serial
Programming, ICSP, ICEPIC, Mindi, MiWi, MPASM, MPLAB
Certified logo, MPLIB, MPLINK, mTouch, PICkit, PICDEM,
PICDEM.net, PICtail, PIC32 logo, PowerCal, PowerInfo,
PowerMate, PowerTool, REAL ICE, rfLAB, Select Mode, Total
Endurance, UNI/O, WiperLock and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other
countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2008, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
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, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS51722A-page ii
© 2008 Microchip Technology Inc.
MCP4725 PICtail™ Plus DAUGHTER
BOARD USER’S GUIDE
Table of Contents
Preface ........................................................................................................................... 1
Introduction............................................................................................................ 1
Document Layout .................................................................................................. 1
Conventions Used in this Guide ............................................................................ 2
Recommended Reading........................................................................................ 3
The Microchip Web Site ........................................................................................ 3
Customer Support ................................................................................................. 3
Document Revision History ................................................................................... 4
Chapter 1. Quick Start Instructions
1.1 Introduction ..................................................................................................... 5
1.2 Description of the MCP4725 PICtail™ Plus Daughter Board ......................... 5
1.3 Getting Started With Explorer 16 Development Board ................................... 6
1.4 Getting Started with PICkit™ Serial Analyzer .............................................. 14
1.5 Examples of The MCP4725 Programming using the
PICkit™ Serial Analyzer ......................................................................... 25
1.6 References ................................................................................................... 26
Appendix A. Schematic and Layouts
A.1 Introduction .................................................................................................. 27
A.2 Board – Schematic ....................................................................................... 28
A.3 Board – Top Layer ....................................................................................... 29
A.4 Board – Top Metal Layer ............................................................................. 30
A.5 Board – Bottom Layer ................................................................................. 31
A.6 Board – Bottom Metal Layer ........................................................................ 32
Appendix B. Bill Of Materials (BOM)
Worldwide Sales and Service .................................................................................... 34
© 2008 Microchip Technology Inc.
DS51722A-page iii
MCP4725 PICtail™ Plus Daughter Board User’s Guide
NOTES:
DS51722A-page iv
© 2008 Microchip Technology Inc.
MCP4725 PICtail™ Plus DAUGHTER
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
MCP4725 PICtail™ Plus Daughter 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 MCP4725 PICtail™ Plus Daughter Board as
a development tool to emulate and debug firmware on a target board. The manual layout is as follows:
• Chapter 1. “Quick Start Instructions” – this chapter provides an overview of the
MCP4725 PICtail™ Plus Daughter Board and instructions on how to program the
DAC register and EEPROM of the MCP4725 device.
• Appendix A. “Schematics and Board Layouts” – shows the schematic and layout diagrams for the MCP4725 PICtail™ Plus Daughter Board.
• Appendix B. “Bill Of Materials (BOM)” – lists the parts used to build the
MCP4725 PICtail™ Plus Daughter Board.
© 2008 Microchip Technology Inc.
DS51722A-page 1
MCP4725 PICtail™ Plus Daughter Board User’s Guide
CONVENTIONS USED IN THIS GUIDE
This manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description
Arial font:
Italic characters
Represents
Referenced books
Emphasized text
A window
A dialog
A menu selection
A field name in a window or
dialog
A menu path
MPLAB® IDE User’s Guide
...is the only compiler...
the Output window
the Settings dialog
select Enable Programmer
“Save project before build”
A dialog button
A tab
A number in verilog format,
where N is the total number of
digits, R is the radix and n is a
digit.
A key on the keyboard
Click OK
Click the Power tab
4‘b0010, 2‘hF1
Italic Courier New
Sample source code
Filenames
File paths
Keywords
Command-line options
Bit values
Constants
A variable argument
Square brackets [ ]
Optional arguments
Curly brackets and pipe
character: { | }
Ellipses...
Choice of mutually exclusive
arguments; an OR selection
Replaces repeated text
#define START
autoexec.bat
c:\mcc18\h
_asm, _endasm, static
-Opa+, -Opa0, 1
0xFF, ‘A’
file.o, where file can be
any valid filename
mcc18 [options] file
[options]
errorlevel {0|1}
Initial caps
Quotes
Underlined, italic text with
right angle bracket
Bold characters
N‘Rnnnn
Text in angle brackets < >
Courier New font:
Plain Courier New
Represents code supplied by
user
DS51722A-page 2
Examples
File>Save
Press <Enter>, <F1>
var_name [,
var_name...]
void main (void)
{ ...
}
© 2008 Microchip Technology Inc.
Preface
RECOMMENDED READING
This user's guide describes how to use MCP4725 PICtail™ Plus Daughter Board. The
following Microchip documents are available and recommended as supplemental
reference resources.
PICkit™ Serial Analyzer User’s Guide (DS51647)
Consult this document for instructions on how to use the PICkit Serial Analyzer hardware and software.
MCP4725 Data Sheet, “12-Bit DAC with EEPROM Memory in SOT-23-6”
(DS22039)
This data sheet provides detailed information regarding the MCP4725 product family.
MCP4725 SOT-23 Evaluation Board User’s Guide (DS51669)
PIC24FJ128GA010 Family Data Sheet (DS39747)
Explore 16 Development Board User’s Guide (DS51589)
AN1079, “Using the C3 Compiler and the I2C Peripheral to Interface Serial
EEPROMs with dsPIC33F” (DS01079)
PICkit™ Serial Analyze User’s Guide (DS51647)
THE MICROCHIP WEB SITE
Microchip provides online support via our web site at www.microchip.com. This web
site is used as a means to make files and information easily available to customers.
Accessible by using your favorite Internet browser, the web site contains the following
information:
• Product Support – Data sheets and errata, application notes and sample
programs, design resources, user’s guides and hardware support documents,
latest software releases and archived software
• General Technical Support – Frequently Asked Questions (FAQs), technical
support requests, online discussion groups, Microchip consultant program
member listing
• Business of Microchip – Product selector and ordering guides, latest Microchip
press releases, listing of seminars and events, listings of Microchip sales offices,
distributors and factory representatives
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Customers should contact their distributor, representative or field application engineer
(FAE) for support. Local sales offices are also available to help customers. A listing of
sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://support.microchip.com
© 2008 Microchip Technology Inc.
DS51722A-page 3
MCP4725 PICtail™ Plus Daughter Board User’s Guide
DOCUMENT REVISION HISTORY
Revision A (March 2008)
• Initial Release of this Document.
DS51722A-page 4
© 2008 Microchip Technology Inc.
MCP4725 PICtail™ Plus DAUGHTER
BOARD USER’S GUIDE
Chapter 1. Quick Start Instructions
1.1
INTRODUCTION
The following sections provide an overview of the MCP4725 PICtail™ Plus Daughter
Board and demonstrate how to use (a) the MCP4725 device in a 16-bit MCU environment and (b) evaluate the MCP4725 device features using the PICkit™ Serial Analyzer
(P/N: DV164122). The MCP4725 PICtail™ Plus Daughter Board is designed to work
with both the Explorer 16 Development Board (P/N: DV164033) and the PICkit™ Serial
Analyzer (P/N: DV164122).
The following topics are covered:
• Description of the MCP4725 PICtail™ Plus Daughter Board
• How to use the MCP4725 PICtail™ Plus Daughter Board with the Explorer 16
Starter Kit
• How to use MCP4725 PICtail™ Plus Daughter Board with the PICkit™ Serial
Analyzer
1.2
DESCRIPTION OF THE MCP4725 PICtail™ Plus DAUGHTER BOARD
The MCP4725 PICtail™ Plus Daughter Board (P/N MCP4725DM-PTPLS) contains an
MCP4725 12-bit Digital-to-Analog Converter (DAC). This daughter board has the following two interfaces:
• Explorer 16 Starter Kit (P/N: DV164033) for 16-bit MCU environment
• PICkit™ Serial Analyzer (P/N: DV164122) for reading and writing the DAC
register and observing the DAC output
The user can connect this daughter board to one of the above tools and perform their
own experiments.
The board has test points for SDL, SDA, and VOUT. By connecting an oscilloscope to
these test points (to SCL, SDA, VOUT) or Digital Multimeter to VOUT, the user can examine the data communications through the I2C™ bus line and observe the resulting DAC
output (VOUT). Refer to Appendix A. “Schematic and Layouts”
1.2.1
I2C Address Bits and A0 Address Bit Selection
The I2C device code and address bits of the MCP4725 device are:
• Device Code: ‘1100’
• A2, A1, A0 Address Bits: ‘00X’, where X is for the A0 bit which is determined by
the logic state of the A0 pin
Note that the first two address bits (A2 and A1) are programmed at factory during
device production and A0 bit is programmed by the user during applications. The A2
and A1 address bits of the MCP4725 device used for the MCP4725 PICtail™ Plus
Daughter Board are programmed at the factory to ‘00’. The JMP1 connector on the
MCP4725 PICtail™ Plus Daughter Board selects the A0 bit. The following conditions
show the A0 bit selection:
• A0 bit = ‘1’ if JMP1 is connected to VDD
• A0 bit = ‘0’ if JMP1 is connected to VSS (Default setting)
• Address bits A2, A1 = ‘00’
© 2008 Microchip Technology Inc.
DS51722A-page 5
MCP4725 PICtail™ Plus Daughter Board User’s Guide
Based on the above information, the combined device code and address bits for the
I2C Serial Communication are:
• 1100-001W/R: if JMP1 is connected to VDD
• 1100-000W/R: if JMP1 is connected to VSS
• Where W/R is write(“0”) or read (‘1’) bit.
FIGURE 1-1:
Board.
1.3
Front and Back Views of the MCP4725 PICtail™ Plus Daughter
GETTING STARTED WITH EXPLORER 16 DEVELOPMENT BOARD
Figure 1-2 shows the MCP4725 PICtail™ Plus Daughter Board with the Explorer 16
Development Board. When they are connected, the user can program the 16-bit
PIC24FJ128 MCU on the Explorer 16 Starter Kit. The Explorer 16 Development Board
sends I2C serial communication commands to the MCP4725 PICtail™ Plus Daughter
Board for the MCP4725 DAC output. The Explorer 16 MCU firmware for this MCP4725
PICtail™ Plus Daughter Board writes to the DAC input register continuously in 1 LSB
increments. The user can see the DAC output (VOUT) changes using an oscilloscope.
Also, a buzzer on the MCP4725 PICtail™ Plus Daughter Board makes sounds driven
by the DAC output (VOUT).
DS51722A-page 6
© 2008 Microchip Technology Inc.
Quick Start Instructions
1.3.1
Connecting to the Explorer 16 Starter Kit
1. Connect the MCP4725 PICtail™ Plus Daughter Board to the J5 socket on the
Explorer 16 Development Board as shown in Figure 1-2.
MCP4725
PICtail Plus
Daughter
Board
Explorer 16 Development Board (P/N DV164033)
FIGURE 1-2:
Connecting the MCP4725 PICtail™ Plus Daughter Board to the
Explorer 16 Development Board.
1.3.2
Programming the PIC24FJ128 MCU
The Explorer 16 Development Board contains the PIC24FJ128 MCU. The user can
download the firmware to the MCU using the MPLAB ICD2 programmer. Refer to
Chapter 2 of the Explorer 16 Development Board User’s Guide (DS51589) for details
on the programming of the Explorer 16 Development Board.
1.3.2.1
THE PIC24FJ128 MCU FIRMWARE FOR THE MCP4725 PICtail™ Plus
DAUGHTER BOARD
The original firmware for the Explorer 16 Development Board is modified for the
MCP4725 PICtail™ Plus Daughter Board demonstration. The firmware uses most of
the original codes for the Explorer 16 Development Board except the I2C peripheral
control routines for the PIC24FJ128 MCU.
The following four routines are added or modified from the original Explorer 16 Development Board firmware.
•
•
•
•
PIC24ExplDemo_MCP4725_Main.c
MCP4725_i2C_Func.c
Banner_MCP4725.c
i2C_MCP4725.h
The user can modify the above routines for their own application.
The source code is compiled by using Microchip’s C30 Compiler and the hex code is
programmed to the MCU using the MPLAB ICD 2. Figure 1-3 shows connection of the
MPLAB ICD 2 and the Explorer 16 Development Board. Figure 1-4 shows the MPLAB
IDE programming environment.
© 2008 Microchip Technology Inc.
DS51722A-page 7
MCP4725 PICtail™ Plus Daughter Board User’s Guide
1.3.2.2
FIRMWARE FLOW CHART FOR THE MCP4725 DAUGHTER BOARD
Figure 1-5 shows the flow chart of the firmware. Once the MCU firmware is programmed, the user can observe the following events:
1. VOUT changes as the MCU rewrites the DAC codes. See Figure 1-6 for the VOUT
waveform.
2. Audible sounds (Buzzer) if JP4 is connected.
3. I2C data communication (SDA and SCL) waveform over the I2C bus line. See
Figure 1-6 and Figure 1-7.
1.3.3
DAC Output (VOUT)
The MCU sends write commands for EEPROM and DAC input register.
The MCU writes EEPROM only once, but writes continuously the DAC input register.
The EEPROM is written for the VOUT = VDD/2, and the DAC input register is continuously written for the VOUT to be ramp: The DAC input code is written from “000h” to
“FFFh” with 1 LSB increment. When it reaches “FFFh”, resets to “000h” and repeats the
writing from “000h” to “FFFh” with 1 LSB again.
The user can observe the VOUT at the VOUT test pin using a digital voltmeter or
oscilloscope. Figure 1-7 shows the I2C clock (SCL) and data (SDA) signals, and DAC
output waveform.
The DAC input register is written with fast mode write command which does not affect
the EEPROM. The user can confirm the data written in EEPROM (VOUT = VDD/2) by
disconnecting the MCP4725 PICtail™ Plus Daughter Board from the Explorer 16
Development Board. When the board is first powered, the MCP4725 device loads the
EEPROM data to the DAC input register by itself and then outputs an analog voltage
determined by the EEPROM data.
1.3.4
Audible Buzzer
The MCP4725 PICtail™ Plus Daughter Board includes a buzzer. This buzzer is directly
connected to the VOUT. The user can disable the buzzer by disconnecting JP4. The
buzzer sounds also can be adjusted by VR1.
DS51722A-page 8
© 2008 Microchip Technology Inc.
Quick Start Instructions
Explorer 16 Development Board
(P/N DV164033)
MCP4725 PICtail Plus
Daughter Board
(P/N MCP4725DM-PTPLS)
FIGURE 1-3:
MPLAB ICD2 connection to Explorer 16 Development Board with the MCP4725
PICtail™ Plus Daughter Board for programming.
© 2008 Microchip Technology Inc.
DS51722A-page 9
MCP4725 PICtail™ Plus Daughter Board User’s Guide
FIGURE 1-4:
DS51722A-page 10
MPLAB IDE Programming Environment.
© 2008 Microchip Technology Inc.
Quick Start Instructions
POWER-UP
(9V)
START
SEND I2C WRITE COMMAND
TO WRITE EEPROM DATA FOR
VOUT = VDD/2
TURN ON LEDS (D4, D6, D8, D10)
DATA = 0
SEND I2C WRITE COMMAND FOR DAC INPUT REGISTER
DAC INPUT REGISTER DATA = DATA + 1 LSB
(VOUT = RAMP FROM 0V TO VDD)
YES
DAC INPUT DATA == 4096 LSB ?
FIGURE 1-5:
NO
Flow Chart for the MCP4725 PICtail™ Plus Daughter Board Firmware.
© 2008 Microchip Technology Inc.
DS51722A-page 11
MCP4725 PICtail™ Plus Daughter Board User’s Guide
I2C
Clock Signal
(SCL)
I 2C
Data Signal
(SDA)
(a) Write DAC Input Register and EEPROM
(DAC Code = 1000-0000-0000)
V DD • Dn
• 800(hex)- = 2.5V
Expected DAC Output = ----------------------- = 5-----------------------------4096
4096
I2C
Clock Signal
(SCL)
I2C
Data Signal
(SDA)
(b) Fast Write Command
(DAC Code = 0110-1101-1001)
V DD • Dn
• 6D9(hex)- = 2.1398V
- = 5-------------------------------Expected DAC Output = ----------------------4096
4096
FIGURE 1-6:
DS51722A-page 12
I2C Write Command Waveforms for the MCP4725.
© 2008 Microchip Technology Inc.
Quick Start Instructions
I2C
Clock Signal
(SCL)
A
A
I 2C
Data Signal
(SDA)
VOUT
at VOUT Pin
A
: Zoomed area for SCL and SDA signals.
Write Data (Dn) = 1111 - 01101111 (binary)
V DD • Dn
V OUT = ----------------------- = 4.823V
4096
FIGURE 1-7:
for VDD = 5V
I2C SCL, SDA, and VOUT Waveforms while incrementing the DAC code by 1 LSB.
© 2008 Microchip Technology Inc.
DS51722A-page 13
MCP4725 PICtail™ Plus Daughter Board User’s Guide
1.4
GETTING STARTED WITH PICKIT™ SERIAL ANALYZER
The user can use the MCP4725 PICtail™ Plus Daughter Board with the PICkit™ Serial
Analyzer by setting up as shown in Figure 1-8.
The following describes how to use them together:
1. Connect the MCP4725 PICtail™ Plus Daughter Board’s J2 pin socket to the
PICkit™ Serial Analyzer.
2. Connect a Digital Voltmeter to VOUT pin and VSS.
MCP4725 PICtail Plus Daughter Board
PICkit Serial Analyzer
Analog Output Voltage (VOUT)
Connected to Voltmeter
USB Cable: Connected between the PICkit Serial analyzer and Personal Computer.
FIGURE 1-8:
DS51722A-page 14
MCP4725 PICtail™ Plus Daughter Board with the PICkit™ Serial Analyzer.
© 2008 Microchip Technology Inc.
Quick Start Instructions
1.4.1
PICkit™ Serial Analyzer PC Software Set-Up for the MCP4725
Daughter Board
The following steps describe how to set and use the PICkit™ Serial Analyzer PC
Graphic User Interface (GUI) to control the MCP4725 PICtail™ Plus Daughter Board.
1. Install the PICkit™ Serial Analyzer software onto your personal computer (PC).
2. Connect the USB cable between the PICkit™ Serial Analyzer and your PC.
3. Run the PICkit™ Serial PC Software: It will open up to the following graphic user
interface (GUI). Click the Next button and follow the instructions:
4. Select the Communication Mode type: I2C Master, and click the Next button.
© 2008 Microchip Technology Inc.
DS51722A-page 15
MCP4725 PICtail™ Plus Daughter Board User’s Guide
5. Select 100 kHz or 400 kHz. Either one will be fine. Click the Next button.
Note:
The MCP4725 device supports the I2C bus data rate up to 3.4 MHz, but the
current version of the PICkit™ Serial Analyzer supports the I2C bus data
rate up to 400 kHz only.
6. Select No on Enable Pull-ups, and click the Next button.
Note:
DS51722A-page 16
The MCP4725 PICtail™ Plus Daughter Board has its own pull-up resistors,
therefore, you don’t need additional pull-up resistors from the PICkit™
Serial Analyzer.
© 2008 Microchip Technology Inc.
Quick Start Instructions
7. Select the VDD voltage of the MCP4725 PICtail™ Plus Daughter Board and click
the Next button.
Case 1: When you use VDD from the PICkit™ Serial Analyzer:
If you choose PICkit™ Serial will power my device and 5 Volts as shown
below, the the MCP4725 PICtail™ Plus Daughter Board is powered by the
5V DC from the PICkit™ Serial Analyer through the JP1 jumper. In this case,
make sure that the JP1 jumper on the MCP4725 PICtail™ Plus Daughter Board
is connected.
Case 2: When you use your own VDD:
You can also provide your own VDD voltage by applying a VDD voltage at TP1. In
this case, make sure that the JP1 jumper is disconnected.
© 2008 Microchip Technology Inc.
DS51722A-page 17
MCP4725 PICtail™ Plus Daughter Board User’s Guide
8. Click the OK button. You have made all of the PICkit™ Serial Analyzer Configuration Set-ups. You are now ready to program the MCP4725 PICtail™ Plus
Daughter Board using the PICkit™ Serial Analyzer.
DS51722A-page 18
© 2008 Microchip Technology Inc.
Quick Start Instructions
1.4.2
Creating Script Files
In order to make a communication between the PICkit™ Serial Analyzer and the
MCP4725 PICtail™ Plus Daughter Board, it needs a script file. The following procedure
shows how to create script files and how to use them.
1. Select Communication -----> Script ---> Script Builder.
© 2008 Microchip Technology Inc.
DS51722A-page 19
MCP4725 PICtail™ Plus Daughter Board User’s Guide
1.4.2.1
CREATING SCRIPT FILES TO PROGRAM DAC REGISTER
1. Click on WriteBlockAddrA8 in “Example I2C Scripts” column.
This will fill in the spaces under Script Detail column.
Modifying the Script Details Parameters:
2. Under the Script Detail column, select the item in the parameter box.
3. Right click the mouse button and an option box appears to the right of your
selection. This gives you the options that are available for the parameter
selected.
4. Select the desired option.
5. Keep the parameters in the same order as shown below:
1.
2.
3.
Choose this box and right
click the mouse button for
options available.
You can also change the
values or delete the boxes.
Make sure the listed
parameters in the “Script
Detail” should be in the
exact order as shown here.
4. Change the parameter value.
Script Detail
I2CSTART
I2CWRTBYT
03
C0
0F
FF
I2CSTOP
Note:
*
*
-----------> This means there are three bytes to send
-----------> 1st Write Byte: Address byte = 1100-0000
-----------> 2nd Write Byte: 0000-1111
-----------> 3rd Write Byte: 1111-1111
*
All 7 parameters above must be listed in order. The parameters with * are
not modifyable. Address bits A2, A1, A0 = 1, 1, 0 if both JMP2 and JMP3
are tied to VDD. You can choose any data you want for the 2nd and 3rd write
bytes. If you use the above write data, the MCP4725 device will output:
V DD ⋅ FFF(hex)(V)
- = V DD ( V )
V OUT = -----------------------------------------------4096
DS51722A-page 20
© 2008 Microchip Technology Inc.
Quick Start Instructions
1st Write Byte
2nd Write Byte
3rd Write Byte
1.4.2.2
SAVING THE SCRIPT FILE AND PROGRAMMING DAC REGISTER
(FAST MODE)
1. Change 2nd and 3rd data bytes you want in the Script Detail.
2. Type in any script name (i.e., MCP4725_Write) in the space below the Script
Name menu.
3. Click Save Script button.
4. Click Execute Script button.
Note:
At this point, the PICkit™ Serial transmits the Fast Write Command to the
MCP4725 device. The saved file name will appear in Users I2C Scripts
column and can be reused any time by selecting the file name.
5. The device provides analog output voltage (VOUT) at the VOUT terminal on the
MCP4725 PICtail™ Plus Daughter Board.
6. VOUT can be monitored by using a voltmeter.
Note:
© 2008 Microchip Technology Inc.
When you click on the “Execute Script” menu, the “Busy” LED on the PICkit
Serial Analyzer will momentarily turn on and then turn off. If the LED
remains ON, a communications problem has occurred. Remove the PICkit
Serial Analyzer from the personal computer and recheck the parameter
value in the order of the parameters under the Script Detail column. Try
again until the “Busy” LED goes OFF after executing the write command.
DS51722A-page 21
MCP4725 PICtail™ Plus Daughter Board User’s Guide
1.4.2.3
CREATING SCRIPT FILE TO PROGRAM DAC REGISTER AND
EEPROM
1. Get a new script file by selecting the WriteAddrA8 from the “Example I2C
Scripts” column.
2. Modify the Script Detail column as shown below:
Script Detail
I2CSTART
I2CWRTBYT
04
C0
60
80
00
I2CSTOP
-----------> This means Master will send four bytes
-----------> 1st Write Byte: Address byte = 1100-0000
-----------> 2nd Write Byte: 0110-0000
-----------> 3rd Write Byte: 1000-0000
-----------> 4th Write Byte: 0000-0000
V DD ⋅ Dn
5V ⋅ 800 ( hex ) = 2.5V
Now the device will output VOUT = ---------------------- = ---------------------------------4096
4096
3. Type in the script name (i.e., MCP4725_EEWrite) in the space below the Script
Name menu.
4. Click the Execute Script button.
1st Write Byte
4 Bytes to Send
2nd Write Byte
3rd Write Byte
4th Write Byte
DS51722A-page 22
© 2008 Microchip Technology Inc.
Quick Start Instructions
1.4.3
Verifying the EEPROM Data
One of the important features of the MCP4725 device is non-volatile memory. When
the device is first powered up, it outputs an analog voltage corresponding to the data
in the EEPROM. The user can confirm this feature using the following procedures:
1. Program the EEPROM memory. Refer to Section 1.4.2.2 “Saving the Script
File and Programming DAC Register (Fast Mode)”.
2. Remove power (VDD) from the MCP4725 PICtail™ Plus Daughter Board, or
remove the daughter board from the Explorer 16 Development Board.
3. Connect power (VDD) to the MCP4725 device.
4. You can confirm the VOUT voltage by using a digital multimeter.
1.4.4
Reading the DAC Register Data using the PICkit™ Serial
Analyzer
You can read back the DAC code stored in the DAC register with the following steps:
1. Create a read command script file name as shown below and execute it.
2. The results (DAC code) will appear on the PICkit™ Serial Transactions page.
Requesting
3 Bytes
Written Data
using a Write Command
Reading Data
using a Read Command
© 2008 Microchip Technology Inc.
DS51722A-page 23
MCP4725 PICtail™ Plus Daughter Board User’s Guide
1.4.4.1
READING BOTH THE DAC REGISTER AND EEPROM DATA:
The following script file can read both DAC input register and EEPROM.
1. Modify the script file as shown below and save it. Click on Execute Script button.
2. The results (DAC code and EEPROM data) will appear on the PICkit™ Serial
Transactions page.
Requesting
5 Bytes
Written Data
using a Write Command
DAC
Register Data
EEPROM Data
Reading Data
using a Read Command
DS51722A-page 24
© 2008 Microchip Technology Inc.
Quick Start Instructions
1.5
EXAMPLES OF THE MCP4725 PROGRAMMING USING THE PICKIT™
SERIAL ANALYZER
1
1
0
Device Code
0
A2
A1
A0
R/W
Address Byte
* Address Byte: A2 = A1 = 0 for Default Samples
A0 = 0 if A0 pin is Grounded
= 1 if A0 pin is tied to Vdd
Example:
Write Mode: 0XC0 for (A2 = A1 = A0)
0XC2 for (A2 = A1 = 0, A0 = Tied to VDD)
Read Mode: 0XC1 for (A2 = A1 = A0)
0XC3 for (A2 = A1 = 0, A0 = Tied to VDD)
FIGURE 1-9:
MCP4725 Device Address Bytes.
11
V REF × Dn
× 2 - = 2.5V
DAC Output = ------------------------- = 5V
-------------------4096
4096
Start
0xC0 ACK
0 0 PD1 PD0 D11 D10 D9 D8 ACK D8 D7 D6 D5 D4 D3 D2
Address Byte:
when A2 = A1 = A0 = 0
0x08
D1 D0 ACK STOP
0x00
11
= 2
FIGURE 1-10:
Fast Mode Write Command for VOUT = 2.5V when VREF = 5V.
© 2008 Microchip Technology Inc.
DS51722A-page 25
MCP4725 PICtail™ Plus Daughter Board User’s Guide
11
V REF × Dn
5V × 2 - = 2.5V
DAC Output = ------------------------- = -------------------4096
4096
Start 0xC0 ACK
0 1
When A2=A1=A0 = 0
1
x
x
PD1 PD0
x
ACK D11 D10 D9 D8 D7 D6 D5 D4 ACK
0x08 = 211
0x60
D3 D2 D1 D0 x
x
x
x
ACK STOP
0x00
FIGURE 1-11:
DS51722A-page 26
Write Command for EEPROM and DAC Register for VOUT = VDD/2.
© 2008 Microchip Technology Inc.
MCP4725 PICtail™ Plus DAUGHTER
BOARD USER’S GUIDE
Appendix A. Schematic and Layouts
A.1
INTRODUCTION
This appendix contains the following schematics and layouts for the MCP4725
PICtail™ Plus Daughter Board:
•
•
•
•
Board – Schematic
Board – Top Layer
Board – Top Metal Layer
Board – Bottom Layer
© 2008 Microchip Technology Inc.
DS51722A-page 27
MCP4725 PICtail™ Plus Daughter Board User’s Guide
BOARD – SCHEMATIC
M
A.2
DS51722A-page 28
© 2008 Microchip Technology Inc.
Schematic and Layouts
A.3
BOARD – TOP LAYER
© 2008 Microchip Technology Inc.
DS51722A-page 29
MCP4725 PICtail™ Plus Daughter Board User’s Guide
A.4
BOARD – TOP METAL LAYER
DS51722A-page 30
© 2008 Microchip Technology Inc.
Schematic and Layouts
A.5
BOARD – BOTTOM LAYER
© 2008 Microchip Technology Inc.
DS51722A-page 31
MCP4725 PICtail™ Plus Daughter Board User’s Guide
A.6
BOARD – BOTTOM METAL LAYER
DS51722A-page 32
© 2008 Microchip Technology Inc.
MCP4725 PICtail™ Plus DAUGHTER
BOARD USER’S GUIDE
Appendix B. Bill Of Materials (BOM)
TABLE B-1:
Qty
BILL OF MATERIALS (BOM)
Reference
Description
Manufacturer
Part Number
1
C1
CAP .1UF 16V CERAMIC X7R 0603
Panasonic - ECG
ECJ-1VB1C104K
1
C2
CAP 1.0UF 16V CERAMIC X5R 0603 Panasonic - ECG
ECJ-1VB1C105K
1
J2
DO NOT POPULATE
CONN HEADER 6POS .100 VERT
TIN
Molex/Waldom Electronics
Corp
22-28-4060
1
JMP1
CONN HEADER 3POS .100" STR
TIN
Molex/Waldom Electronics 90120-0123
Corp
3
JMP1, JP1,
JP2
SHUNT LP W/HANDLE 2 POS 30AU
Bag shunts with kit
Tyco Electronics/Amp
2
JP1, JP2
CONN HEADER 2POS .100 VERT
TIN
Molex/Waldom Electronics 22-03-2021
1
PCB
RoHS Compliant Bare PCB,
MCP4725 PICtail Plus Daughter
Board
—
104-00186
1
R1
RES 100 OHM 1/10W 1% 0603 SMD
Panasonic - ECG
ERJ-3EKF1000V
2
R2, R3
RES 10.0K OHM 1/10W 1% 0603
SMD
Panasonic - ECG
ERJ-3EKF1002V
4
R4, R5, R6, R7 RES 0.0 OHM 1/10W 5% 0603 SMD
Yageo Corporation
RC0603JR-070RL
1
SP1
BUZZER PIEZO 3KHZ 24MM PC MT Mallory Sonalert Products
Inc
PK-21N30PQ
5
TP1, TP2, T3
TP4, TP5
PC TEST POINT COMPACT SMT
Keystone Electronics
5016
1
U1
12-Bit Digital-to-Analog Converter
with EEPROM Memory in SOT-23-6
Microchip Technology Inc
MCP4725A0T-E/CH
1
VR1
POT 5.0K OHM THUMBWHEEL
CERM ST
Bourns Inc.
3352T-1-502
Note 1:
881545-2
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.
© 2008 Microchip Technology Inc.
DS51722A-page 33
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://support.microchip.com
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Harbour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-4182-8400
Fax: 91-80-4182-8422
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
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
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
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
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
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Hsin Chu
Tel: 886-3-572-9526
Fax: 886-3-572-6459
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
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
China - Zhuhai
Tel: 86-756-3210040
Fax: 86-756-3210049
01/02/08
DS51722A-page 34
© 2008 Microchip Technology Inc.
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