IRF510 and DC Motor

Thread Starter


Joined Nov 6, 2009
I built a 555 based circuit to turn a 12 volt DC motor on and off cyclically.
The 555 circuit is running perfectly now (thanks to a lot of help from this site) but I a having some problems with the IRF510 that I am using. Instead of turning on and off, the motors goes fast and slow. Any ideas why this would happen?

The circuit I built is shown in the attachment. The only thing I don't have is D1 (1N4148) and I swapped the relay for the IRF510.

Thanks for taking the time to read.