L298 H-Bridge PCB Project

April 1998, by Jim Brown
August 2002, page format revised, links update by NCC
July 2004, additional graphics provided by Bob Jordan

Project Summary

The goal of this project is to create a carrier board for an L298 H-Bridge with 1000mf cap, 12 diodes, a terminal block for power and two motors, and a header for interfacing with a microcontroller. The board is based on a simple L298 H-Bridge design by Clay Timmons.

Note that the board can be made using just the bottom artwork. The top artwork is informational only and contains text explaining diode orientation and pinouts.

Photo of assembled v1.1 L298 H-Bridge Board

Color image of v1.0 PCB artwork

Flipped v1.0 PCB artwork (click image for larger view)

Component placement (click image for larger view)

Schematic Diagram

 MOTOR & POWER HEADER                                  TO CPU HEADER
                                  +--------+
 Motor power+ -+-+-+-+-+----------|        |----------- in 1
               | | | | | 1000mf   |  L298  |----------- in 2
               _ _ _ _ +--|(---+  |        |----------- enable a
               ^ ^ ^ ^         |  |        |----------- in 3
    Gnd * -----|-|-|-|-+-+-+-+-+--|        |----------- in 4
               | | | | | | | |    |        |----------- enable b
               | | | | v v v v    |        |----------- curr sense a
               | | | | - - - -    |        |----------- curr sense b
               | | | | | | | |    |        |
  Motor 1 ---+-+-|-|-|-+-|-|-|----|        |-----+----- +5
          +)(+   | | |   | | |    |        |     +)(+
          +------+-|-|---+-|-|----|        |--------+-- Gnd *
                   | |     | |    |        |
  Motor 2 ---+-----+-|-----+-|----|        |
          +)(+       |       |    |        |
          +----------+-------+----|        |
                                  +--------+
 
 * Grounds are connected.

 You use in1 & in2 for direction and enablea for pwm for motor 1
 You use in3 & in4 for direction and enableb for pwm for motor 2

The Details

• L298 v1.0 PCB data file for Protel EasyTrax
• L298 v1.1 PCB date file for Protel EasyTrax
• L298 PCB Artwork - PDF format
• L298 PCB Artwork - Postscript format

For more information, see the DPRG tutorial entitled, H-Bridge Theory of Operation.

Copyright © 1998 Dallas Person Robotics Group

The L298 H-Bridge PCB artwork is licensed under version 2 or later of the GNU GPL. This means everyone has the freedom to use this design for any purpose, to study it, to copy it, to distribute it, and to change or improve it, provided such changes are also made freely available to everyone.