i know this is a topic which has been discuused earlier but...could you please let me know if its possible to design a pwm contoller for this specification and how the values of the components have to be calculated.
thank you

 

Yes. Google is your friend. But you also don't give enough information to get help.

 

See m planning on bulidin a pwm spped controller for pmdc...planning on using an ic555.. and a power mosfet.., but I am confused on how to callculate the componnet values..the value of the pot etc!
Ps:resistance can also be( roh*l)/A

 

Here is a starter circuit, to increase the current use a bigger mosfet

http://www.google.co.uk/imgres?imgu...C21VUfH2BsOyPOSygKAB&ved=0CEEQ9QEwBQ&dur=1785

 

Here is a starter circuit, to increase the current use a bigger mosfet

http://www.google.co.uk/imgres?imgu...C21VUfH2BsOyPOSygKAB&ved=0CEEQ9QEwBQ&dur=1785

@Dodgydave, good for a starter circuit, but one bad thing about that circuit is, as the duty cycle (speed) is changed the frequency of the 555 also changes.

One our moderators here, Bill Marsden shows a more stable PWM circuit that is not much more complicated. Figure 5.3 in this link shows a very good stable circuit. And a good tutorial for PWM.
http://forum.allaboutcircuits.com/showpost.php?p=117641&postcount=6

 

Thanks a lot guys! For taking time out to answer ll check them out