3 Amp PWM DC Motor Controller

3 Amp PWM DC Motor Controller Published in issue 367, July/August 2007

This circuit is intended for motion control applications, a common occurrence in robotics! This affordable PWM DC Motor controller can control any PMDC motor specified at 12V to 30V and 3Amps max. Motor direction is controlled with a slide switch and motor speed, with an ordinary potentiometer.

The circuit diagram in Figure1 shows ICs type LMD18200 and SG3525 at the heart of the circuit. The SG3525 is a pulsewidth modulator control circuit and the LMD18200, an H-Bridge to enable the motor to be run in both directions.

Components

Relevant productsResistorsR1 = 10k

R2,R4 = 18k

R3 = 2k2

R5 = 330

R6 = 2k7

R7 = 1k5

P1 = 10k potentiometer

P2 = 100k preset

CapacitorsC1,C2,C4,C5,C7, C9, C10 = 100nF

C3 = 18nF

C5 = 22F 63F

C6,C8 = 100F 63V

SemiconductorsD1,D2 = LED

IC1 = SG3525AN

IC2 = LMD18200

IC3 = L7805ACV

MiscellaneousK1,K2,K3 = 2-way PCB terminal block, lead pitch 5mm

S1 = slide switch

PCB, ref. 060339-1 from www.thepcbshop.com