Corsair Power Supply CX600 - Page 1
Forum section: electronics / projects

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: January 27, 2019, 01:39:10 pm
content: I am trying to repair a Cosrair power supply which first started having problems starting up then stopped working completely. There is no output and the fan does not spin up when the green wire is connected to GND. There are no obvious signs of the smoke being let loose or other physical damage. The capacitors have been replaced and the opti-isolators checked. I have also replaced the TL431. So far there is still no life from it.There is another IC in a 16-pin DIP package that I can't identify. The markings were read even under a microscope with difficulty and appear to be as follows:SitronixST95429-PG14 (or ST9S429-PG14 - see below)FL OM6 (or FL 0M6)T4288I am unable to find any information on it. A search turns up the usual mix of false/broken datasheet links and a possible alternative search term of ST9S429-PG14, but no datasheet information for either reference. There are a few links to components beginning with ST90* but nothing relevant.Does anyone have information about this part? Possibly ST95429-PG14 or ST9S429-PG14?

author: mvs
author_rank: Frequent Contributor
timestamp: January 28, 2019, 07:08:31 am
content: Quote from: WaveyDipole on January 27, 2019, 01:39:10 pmST9S429-PG14 has DIP-14 package, not DIP-16. It is psu supervisor ic compatible with S3515http://www.unisonic.com.tw/datasheet/S3515.pdf

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: January 28, 2019, 01:41:09 pm
content: My apologies. It is indeed a 14-pin dip. Must have got cross-eyed or something when I counted them!The link to the datasheet on the S3515 gives me something to work from and I have found quite a bit more useful information by searching on that part number, so thanks for the information.

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: January 29, 2019, 04:30:58 pm
content: Hmmm.. I found 5v on the VCC input but nothing much else of interest around that IC. I also pulled the PFC daughterboard out to have a look at. It has a CM6800TX 16-pin dip chip on it and an 8 pin CM03X on the reverse. I powered the board with the typical 15v and measured +7.495 on the Vref pin. I also have a 376kHz ramp on RAMP1 using the oscilloscope. However, there seems to be nothing on RAMP2, PFC OUT and PWM OUT. But then, with the board being out of circuit, I'm not sure whether it needs external signals.I'm had a search but I'm struggling to find a datasheet for the CM03X chip. I found the IC for sale on Alibaba, Aliexpress and Kynix, but once again, datasheet links (where available) were broken. Other search links seem to point to ceramic capacitors....Can anyone help with a datasheet reference to the CM03X chip?Can anyone confirm what signals I should be seeing on the 6800 chip?

author: Appocalypse_br
author_rank: Contributor
timestamp: April 24, 2019, 06:40:42 pm
content: Hi i have the cm03x is a triple mosfet enclosure, the cm6800 is probably the fault, just replace it.I am from BRASIL corsair psu repair specialist. Good luck.

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: May 01, 2019, 07:12:35 pm
content: Thanks. I have now replaced the CM6800 but still no sign of life from the PSU unfortunately.

author: Appocalypse_br
author_rank: Contributor
timestamp: October 03, 2019, 07:22:16 pm
content: Check if the transistor from de opto is switching, from 16v to 14v there is your enable, check all the low value resistors and ceramic caps, should solve your problem.

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: May 30, 2020, 05:18:12 pm
content: I've had this sitting on the shelf for months and finally got around to having another look and I have managed to get it working! However, there is still a problem.I had already replaced the three optos before I shelved the repair, but I checked the voltages as you suggested anyway and found only residual voltages of around 0.5 to 1.5v. In fact pretty much the entire circuit seemed rather dead. There was close to 400v across the large smoothing capacitor after the rectifier and up to the MOSFETS but that was about all. Nothing at the MOSFET gates to drive them. There was a large resistor which was rather tight to get and while de-soldering this, I accidentally de-soldered the wrong pin. Turns out it was one of the input transformer legs and that joint may have been the problem! The resistor turned out to be perfectly fine so I put it back and re-flowed the joint I disturbed in error. After that, the supply worked. Could have been the transformer leg, or could have been the resistor joints I suppose.The caveat is that the supply fan comes on immediately without shorting the green wire to ground but runs quite slowly and quietly. Otherwise, the 12V, 5V and 3.3V lines measure spot on. I am not sure whether it can deliver the full load current but am not sure how to test?