Cooler Master RS-400-PSAR-13

[everell]

Recently acquired this clean good looking Cooler Master power supply. The 5VSB works OK, but the power supply is otherwise dead. Not even a fan twitch. Fuse not blown and no evidence of any burnt or blasted components. So.............

This is a half bridge SMPS. First place I looked was the two outputs of the pwm chip, a 2012 "chip of the year". Nothing. Very seldom that I get a pwm chip that does not put out something! Used a digital voltmeter to check the Vcc pin, reading 0.2 volts. Not enough to get a signal output! From the 5vsb, a 10 ohm resistor, then a steering diode, and then the Vcc pin. So I measured the resistance from the Vcc pin to ground. Only 24 ohms. Lifted one side of the diode and removed two filter capacitors from Vcc pin to ground. Still 24 ohms. So I removed the pwm chip and there it was, 24 ohms from the Vcc pin to the ground pin on the pwm chip.

This should be a simple fix. Just replace the pwm chip. Right??? I have traced the pins on several "chip of the year" series, 2002, 2003, 2005, and 2012. But so far I have never found a substitute chip on the market (Digikey, Mouser, or ebay). Has anyone found a direct replacement? Hate to toss a clean power supply over something as simple as this.

[Dan81]

Re: Cooler Master RS-400-PSAR-13

It's a Deer, just so you know. Try harvesting a 2005 chip from another Deer (or a 2003, that works too) and it should come back to life.

[momaka]

Re: Cooler Master RS-400-PSAR-13

Oh Deer!
I wonder what happened to that PWM chip. Did the 5VSB overshoot so badly that it killed it? Or perhaps the 12V rail?

Funny thing is, I have an Allied PSU here that is almost exactly identical to yours (only the heatsinks are a bit taller and different shape) - it has a blown fuse and blown BJTs. Uses the same 2012 "chip of the year" IC. I sure pray mine hasn't blown too.

That said, I think what Dan81 suggested may be the easiest option. Other options would be to make a small PCB with an SG6105 or ATX2005 chip and wire the pins accordingly to the board (probably won't match what the "2012" chip has).