How to Use a 555 Timer for PWM

[pzentrady]

i need to use PWM and i want to make it myself from 555timer.But i don't know how to make it if somebody there know please tell me about it

 

[smokyLED]

here's an example of a pwm to contorl a motor, http://www.dprg.org/tutorials/2005-11a/

otherwise the 555 datasheet might be useful, http://www.fairchildsemi.com/ds/NE%2FNE555.pdf

 

[reuben1]

ahhh!!!    thanks!  that's a better circuit than i the one i have,  I'll use that to drive the little power transistors that drive the really big ones that run the 15hp forklift motor that i installed in a subaru wagon to make a HE car.    RT

 

[indulis]

One thing that will happen when using a 555 as PWM is that the switching frequency will change with line and load.

 

[reuben1]

I did notice that,  the circuit i have runs at several hundred Hz with a lot of frequency change along with the pulse width change,  i ran a tape recorder motor with it, it ran fine from 0 to full speed, then put a  speaker on it to hear what it's doing.  I'll try this one and see if it does better.

 

[smokyLED]

you should post of picture of the 15hp motor installed in ur car