Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Trumpkin on February 10, 2009, 10:32:12 AM

Title: MOSFETs instead of relays?
Post by: Trumpkin on February 10, 2009, 10:32:12 AM

In the "Build Your Own Butler Robot" tutorial couldn't you use Power MOSFETs instead of relays? It seems like MOSFETs would be a lot smaller and cheaper than relays.

Title: Re: MOSFETs instead of relays?
Post by: MaltiK on February 10, 2009, 02:26:10 PM

MOSFETS capable of driving the motors he used were, as he mentioned, beyond his budget.

Also I dont know if you can connect MOSFETS directly to the output of the phidgets like what he did with the relays, I am not sure but I think you need a middleman, an MCU.

Title: Re: MOSFETs instead of relays?
Post by: Trumpkin on February 10, 2009, 02:37:59 PM

Wouldn't this H-bridge work? http://www.societyofrobots.com/schematics_h-bridgedes.shtml

Title: Re: MOSFETs instead of relays?
Post by: MaltiK on February 10, 2009, 02:41:25 PM

I always found it wierd that due to the small size of MOSFETs, it would be really hard for me atleast, to accept the fact that they can power motors with as high a current stall as 25amps...