Soft start of DC-DC converter on STM32G474

[DmytroAnishchenko]

Hello. I created a DC-DC converter on a G4 series microcontroller. I use hardware FMAC, current mode as the regulator. My question concerns the overregulation of the output voltage level when the converter starts. I have a hardware power-off button on board, namely the physical disconnection of the battery from the converter, as well as a clock switch for the user, which directly turns on and off the conversion process, and the user configures some parameters. Soft start is not implemented in software. The situation is as follows, the first start of the converter after turning it on with the power button goes through overregulation, which I can confirm with oscillograms. But all subsequent starts are accompanied by a short-term overregulation of the output voltage level. Please, anyone who wants to help me, respond, I will provide all the necessary information upon request. I want to reset the oscillograms in the next post.

[DmytroAnishchenko]

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On the oscillograms, the blue ray is the output voltage, the purple is the inverse sawtooth generated by the DAC, which is compared with the choke current (current mode) in the built-in comparator. The first oscillogram is the first start after turning on the device - there is no overshoot, a characteristic increase in the amplitudes of both signals. The second oscillogram clearly shows the overshoot.

I performed some manipulations with the involved peripherals, but without result. My last suspicion concerns the FMAC module. I tried to reset the settings and reconfigure, when restarting - without result. Resetting the FMAC, I tried to reset the twisted PID channels by the previous conversion. So far, these are my thoughts.