I Did it at last. It took me some months to complete this simple-looking circuit.

I had 6 3-wire 120mm fans in stock and did not know how to use them. Now i have already order some more

I wanted to have a PWM rpm fan controller along with rpm feedback from the fan. Believe me, when you PWM the fan you get in troubles doing it.

The i 'altered' the original idea a little bit more, and converted the PWM generator into a simple variable power supply:
http://pcbheaven.com/circuitpages/PWM_Fan_controller_using_a_555

It did work but it was just NOT a pure PWM fan controller.

No more talking. I present to you my PWM masterpiece:
http://pcbheaven.com/circuitpages/Two_Speed_Temperature_Fan_Controller

This is a real PURE PWM fan controller and it does MUCH much more:

1. It uses simple DC 3-wire fans
2. It uses PURE PWM pulses to rotate the fan
3. It can achieve speeds as low as 600rpm without staling
4. The fan sends rpm feedback to the controller
5. The feedback can be used for rpm indication (easily)
6. The feedback IS used to check the speed of the fan. If the speed is NOT within the +-10rpm limit, the controller automatically micro-adjust the duty cycle of the PWM

I spent an enormous amount of time to make it work and feel prod of it. Looks easy but believe me, it is not.

Thank you, and sorry for this rather pointless message. I just feel the flame inside me burning

 

Kammenos, nice project! Clever indeed!

Please, read the third commandment and if you could remove your joke at bottom page, I will appreciate it very much.
Thank you for your kindness.

Alberto

For what joke you talk about Alberto?

 

About your signature which you think is a credit !!

 

About your signature which you think is a credit !!

Aha THAT


Well, hopefully, if the administrators have no problem with this, neither do i. I understand that religion is a very personal thing, but i really believe that i insult NO believes or religions. Really. Correct me if i'm wrong.

If your comment is made for my own good, then i have to thank you for your concern and i will really think about it.
If the comment is made for pleasing your own vanity, then allow me to call for my "right of speech" and recall the "administration's position" for the subject.

If you DO feel insulted after all, then there is nothing that i could do about it.

 

Left to you Alberto..