Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Problem with DC motor circuit

Status
Not open for further replies.

krishnan.asish

Newbie level 2
Joined
Jan 26, 2012
Messages
2
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,304
Iam using a PIC17F877A micro-controller to drive two DC motors (which I got from identical small toy cars) via L293D h-bridge.
I don't know about the specifications of the motors as they are from quite old toys (about 1.5 years old). So the main problem is that the DC motors need a little manual rotation to make it start rotating again and it has a tendency to stop especially when the direction of the motor is made to change according to the code which designed. Also when I used another code (speed regulation via PWM signals) the motor didn't start rotating .It just produced a 'whir' sound and require the initial manual rotation. Iam using a 9V supply to drive the motors via the h-bridge. A single motor runs more faster as if it gets more voltage or power than when I connected two motors to the h-bridge. Can somebody help me with these problems?
 

My guess is that the motors need more current than you supply to rotate. The driver is specified for max 600mA and drop approximately 3V at that current.
What was the battery voltage in the toys? Have you measured the start current of a motor at that voltage.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top