I’m posting here as well as emailing RealDigital, but thought maybe some folks might have some experience.
Board: RFSoC4x2, PYNQ: v3.0.1, FW: custom, based of RFSoC-MTS
Recently, I have not been able to boot up my RFSoC4x2. When the board is powered off, after I flip the power on switch, I only see the VIO, SEQ_OK, RF_LDO LEDs come on. The fan stays off, and I hear no sounds (clicking, etc.). The LEDs also don’t pulse or cycle or anything. I have tried a separate microSD card with PYNQ v3.0.1 flashed, but no luck. My guess is it’s something wrong with the board (see the attached schematic). I have probed the C664, C665 caps, and the voltage for VCCp12V0 is at 8.92V, so sagging. Probing the C659, C660 caps (VCCp12V0_FILTERED), I find these at 12.21V, so normal operating voltage. My guess then is the IC54 chip (LM25069PMM-1/NOPB) isn’t operating correctly, since its GATE OUT pin must not be fully switching the Q19 (CSD18510Q5B) MOSFET. Also, since VCCp12V0_FILTERED is at 12.21V, I don’t expect it has to do with my power supply.
My worry is that during operation, I may have accidentally shorted something on the back of the board. However, during data taking, I found nothing suspicious, and when I was finished, I powered down the board. Only when I tried to power it on again did this start to happen. I should also say that I’ve sometimes had the board not boot up on me, normally if I switch the board back on too quickly during a power-cycle (I find I need to wait like 20 seconds or more). But I’ve never had it fail to boot more than once in a row.
Has anyone had something similar before? Any ideas of how to debug?
