for pwm generation 555 or schmitt trigger

[aruna1]

which is good for generating pwm for motor control?
555 timer or 7414 schmitt trigger ic? and why?
thanks

 

[mneary]

555 hands down. Its thresholds are more tightly controlled than 7414.

You can get circuits on the net for 555 (best place to start is the App notes at National).

 

[QuietMan]

555 Schmitt Trigger

 

[smanches]

555 as a sawtooth generator.
Any comparator to generate it into a PWM signal.

A 555 by itself is not frequency stable when varying it for PWM.