[SOLVED] HISSSS Noise in stepper motor

[amayilsamy]

I have unipolar stepper motor while its running its generate HISSS noises .... how avoid it??

here I attached my driving circuit.. I'm using chopper driver circuit..

**broken link removed**

Logic supply voltage : 5V

Motor supply : 9.0 V

 

[amayilsamy]

I'm using damping method to avoid the resonance from the stepper motor...