Microchip Technology dsPICDEM 1.1 Modification Instructions

dsPICDEM™ 1.1

DEVELOPMENT BOARD

3.3V RETROFIT

© 2005 Microchip Technology Inc. 3.3V Retrofit Rev 1.0-page 1

Modification Instructions

1.1 DSPICDEM 1.1 DEVELOPMENT BOARD 3.3 VDC RETROFIT

This retrofit allows the dsPICDEM 1.1 Development Board (DM 300014, PCB
Assembly 02-01719) to be used as a development tool for both dsPIC30F and
dsPIC33F devices. The development board is modified to replace the digital voltage
regulator, remove the analog voltage regulator and replace transceiver chips with
substitute components that support a wider range of operation (2.8–5.5 VDC).

After completing this modification you will be able to interchangeably work with 3.3 VDC
or 5 VDC devices by simply adding or removing the jumper on the voltage regulator
miniature board.

Other development boards that support both dsPIC30F and dsPIC33F devices include:

• dsPICDEM™ 80-Pin Starter Development Board (Part # DM300019)

• Explorer 16 Development Board (Part # DM240001)

If you have, or wish to purchase, one of these boards you probably don’t need to retrofit
your dsPICDEM 1.1 Development Board.

If you do modify an existing dsPICDEM 1.1 Development Board, you are responsible
for maintaining good workmanship practices. To avoid damage to the printed circuit
board, it is strongly recommended that components be removed by first cutting the
leads and then unsoldering the remaining lead remnants.

Contact your sales representative or DSCD marketing for additional information.

Note: The LCD is not currently supported when 3.3 VDC operation is selected.

THE DSPICDEM 1.1 DEVELOPMENT BOARD 90-DAY WARRANTY WILL EXPIRE
IF YOU MODIFY THE BOARD (REGARDLESS OF WHETHER YOU USE THESE
MODIFICATION INSTRUCTIONS OR PERFORM YOUR OWN MODIFICATIONS).

THE MODIFICATION INSTRUCTIONS ARE SUPPLIED BY MICROCHIP "AS IS".
MICROCHIP DOES NOT WARRANT THAT THE OPERATION OF THE
DEVELOPMENT BOARD, ITS FIRMWARE OR SOFTWARE WILL BE ACCURATE,
UNINTERRUPTED OR ERROR-FREE.

It is your responsibility to ensure that the board continues to function properly and any
application you develop meets your specifications.

dsPICDEM™ 1.1 Development Board 3.3V Retrofit

3.3V Retrofit Rev 1.0-page 2 © 2005 Microchip Technology Inc.

1.1.1 What You Need

The following table lists the parts you need for this modification. Except for the
RS422 Transceiver used with the RS-485/RS-422 port, all these parts are contained in
a retrofit kit.

Item

Ref.

Des.

Qty Description Value Mfg Mfg Part #

Parts on dsPICDEM 1.1 Development Board

1 U1,U3 2 IC SMT, Driver, RS232 Xmtr/Rcvr,

16-SOIC(wide)

—

MAXIM MAX3232CDWR

2 U12 1 IC SMT, 3.3V CAN TX/RX, 8P

SOIC (0.150")

—

TI SN65HVD230DR

3U41RS422

(See Note 1)

—

MAXIM MAX3491ECSD

Parts on Regulator Adapter Board

4 VR1 IC Positive Adj Regulator TO-263

—

National
Semi

LM317S

5 J1 1 2 Pin.100, SMT header

—

Samtec

TSM-102-01-S-DV

6 R1 1 Resistor, 1206 412R Rohm MCR18EZHF4120

7 R2 1 Resistor, 1206 249R Rohm MCR18EZHF2490

8 R3 1 Resistor, 1206 294R Rohm MCR18EZHF2940

9 1 PCB Assembly

—— —

10 3 Jumper wire

—— —

1: This part is not supplied in the retrofit kit. The RS422 Transceiver will only need to be

replaced if your application uses this feature with 3.3 VDC operation.

Note: The modification kit does not include a dsPIC33F device. It must purchased

separately.