Other Parts Discussed in Thread: LM3481, CSD19538Q3A, CSD17577Q3A
Hello, I have implemented PMP20183 for the most part copying the schematic and layout except for modifying the R2,R100 and R3 according to post "PMP20183: PMP20183 Voltage modification" on these forums to 6.34k, to lower the overall output voltage. However, I am reaching an issue hitting the target voltage, from what appears to be excessive current draw. Essentially, the LM3481 drives the FET for a few ms, the 12V power supply voltage goes down, eventually triggering the UVLO. It then takes some time to recover. The overall output voltage is around 100V, well below the expected. The thing is the overall circuit is only drawing ~150mA, so it's not overloading my power supply, so I figured it might just need more capacitors (not listed on the design) for burst current, however adding a a few more 22uFcaps, and then a 1000uF cap to the supply and near the inductor seems to make the driver run for longer, but then the overall current becomes something like 0.5A, the final output voltage only reaching something like 110V. I also tried increasing the input voltage, and at ~12.5V the current spikes up again and blows the mosfet. Kind of tearing my hair out about this, so any help would be great!
I attached some waveform, yellow is output voltage, blue is the drive signal. Isense voltage seems below 200mV.