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?