Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: jaden845 on July 16, 2012, 06:43:20 AM

Title: Advice on choosing a motor controller chip please
Post by: jaden845 on July 16, 2012, 06:43:20 AM
Hi.

I am beginning to build my first robot and am looking to build a motor controller circuit using the H-Bridge configuration. I shall be using the PIC18F4520 http://docs-europe.electrocomponents.com/webdocs/0806/0900766b80806cf6.pdf (http://docs-europe.electrocomponents.com/webdocs/0806/0900766b80806cf6.pdf) along with a 9V battery and 2x DC motors rated at 9V with a caster wheel at the front of the robot.

Could anyone please advise me of a reasonably straightforwards motor controller chip that would work with my microcontroller and the H-Bridge configuration?

Thanks
Title: Re: Advice on choosing a motor controller chip please
Post by: pterrus on July 16, 2012, 01:55:06 PM
The L293D has worked well for me and is really easy to set up.
Title: Re: Advice on choosing a motor controller chip please
Post by: jaden845 on July 16, 2012, 03:21:04 PM
Ok thanks JR I shall give one a try and let you know how I do!
Title: Re: Advice on choosing a motor controller chip please
Post by: Soeren on July 16, 2012, 06:52:57 PM
Hi,

The L293D (600mA max) has got a high voltage drop (up to 3.6V), so you may end up with as little as 5.4V for the motors (with a fresh battery).

Try the FAN8200 series (Fairchild) instead, if the current is below 650mA. It comes in four variants:
FAN8200 = 650mA max.
FAN8200MTC = 550mA max.
FAN8200D = 400mA max.
FAN8200MP = 350mA max.
(Each will drive 2 separate DC motors)

If your motors need more current, you need something else of course, but there's so many motor driver chips that it wold be pointless mentioning any without knowing the current your motor takes when loaded.
Title: Re: Advice on choosing a motor controller chip please
Post by: jaden845 on July 17, 2012, 07:01:06 AM
Soeren,

Thanks for your input. I shall decide on the motors to use and bear that in mind.