First version ready to be built:2 x 35W Manual Control
Buck converter based, 2 channels, up to 35W per channel with small heatsink on MOSFET. Superior to basic PWM drive, and much more powerful than regular linear drive.
Goes all the way from off to full speed.
Design based on commonly available components.Diagram:PCB Layout:PCB Back side - Negative (300 DPI)PCB Back side - Positive (300 DPI)Materials needed
4 x 1N4148 (D2, D3, D5, D6)
2 x 1N5822 (D1, D4)
2 x 3nF (C3, C6)
2 x 20K Potentiometer Lin (R3, R4)
2 x 100R (R1, R2)
2 x 100uH/3A (L1, L2)
3 x 470uF/50V or 220uF/25V (C1, C2, C4)
8 x 3 pin fan socket
2 x MTP50P03HDL (or similar TO220 low voltage high amp MOSFET p-channel) (Q1, Q2)
2 x NE555 (IC1, IC2)
1 x Molex power socket (optional)
Plus some circuit board and the optional heatsinks for mosfets (TO220 small size)
All needed components are available at e.g. www.digikey.com
I can add links if interested.Built and tested (1 channel for testing)Load testing 1 channel:
(with 12 fans)
Have fun and feel welcome to ask for any questions, and let me know if you find any mistakes post a picture if you build one
Note: It is possible to take the RPM (tachometer) output from 1 fan on each channel and plug it into the motherboard for monitoring, if anyone is interested I can post a wiring diagram.
Edit: added DPI on the Layout)Edited by jvjessen - 6/28/12 at 9:49pm