Here is one circuit that could be adapted for what you need.
see
http://www.bit-tech.net/article/51/
It's Pulse Width Modulated circuit is more efficient that a regular transistor circuit and it's produces less heat.
Best regards
frenchnew
Quote:
|
Originally Posted by DeadEye
Having done searches with Google and through many forums I have come to the conclusion that what I am suggesting here hasnt been done. Please correct me if I am wrong.
High power fans are not able to be connected to mobo headers due to their lack of current handling abilities, usually 0.5A max. So fans then have to be connected to molex connector via adaptor for supply.
The problem with this is although the speed can be monitored by wiring back to the mobo fan connector, it now lacks speed control by software like Speedfan or similar.
Would it not be possible to make a small circuit that adds pass transistor or FET output stage that is controlled by the mobo header but is powered from the molex.
To me this has to work. Can some one draw us a circuit for this?
Thanks
|