dc motor and back emf

Thread Starter


Joined Jul 25, 2007
I have just build a motor controller using PWM and containing a back emf feedback. The motor used is a typical toy motor which operate with a 6V supply. when applying 6V under no load, i found that the Back emf is only 0.9V.

Can someone explain why this value? I would have expected a value of more than 2V for the back emf