Electronics PWM fan controller article

all i can say is. my rheobus now works! thanks to cpemma!!! i copied your circuit and added a LED. though my voltage rating is just 10v, it'll be fine for me. but, im wondering how i can amplfy voltage? i want it to reach 11.5v or 11.7v

 

Which circuit?

 

this one:

 

You'll only get about 10.3v max output with a 317, for a bit more use my emitter-follower circuit (to 11.3v) or for even more (11.8+) macromans low-drop-out regulator. For the full monty, the diobus. :dude:

Link in Useful Links

 

which useful links man? here or at cpemma.co.uk?

 

Hehe, I think he means his Useful Links thread here http://forums.bit-tech.net/showthread.php?s=&threadid=4589

The links at his site aren't specifically called "useful", although they do have their uses

 

macroman, is using a PWM. MIC IC are not available here. can you post the emitter follower circuit?

 

http://www.cpemma.co.uk/ef.html

 

Thanks, CrazyJester, 76 posts, like your new avatar, though mad matador came to mind

 

It's Jester from the Puppet Master and its sequels, my actual "Crazy Jester" is nowhere to be found... probably on a backup disk in a pile somewhere I might find it, or recreate it, or just leave this on here for a while

 

thanks guys!

 

btw, if i were to put a LED here:



where should it be? it gona eat up voltage right?

 

You'd want to put it across the fan. The only thing is that an led's brightness doesn't scale well with voltage... It depends what you want the led to indicate

 

Across the fan as CrazyJester says (with a suitable series resistor calculated on a 11.3v max, eg 390R for a 3.7v blue @ 20mA), but to get a decent dim as you turn the wick down try this idea..

The extra 20mA led juice is negligible compared to a typical fan.