I found a confusing phenomenon that I found when using STM32G431CBU6 OPAMP3 works in Timer controlled mode.
At first,I let the OPAMP3 works in FOLLOWER,the TIM8 channel6 to trigger the change of VIN_P and VIN_P_SEC. This is the settings of the STM32cubeMX.
When the input is VIN_P, the output is equal to the input.But when the input is VIN_P_SEC,the output is twice the input. This is the oscilloscope waveform.The yellow is the signal input in the VIN_P and VIN_P_SEC,the blue one is the output.
Therefore, I suspect that VIN_P_SEC perhaps in PGA mode. So I switched the FOLLOWER mode to PGA mode.This is the settings of the STM32cubeMX.
In this mode, when the input is VIN_P, the output is twice as much as the input and VIN_PSEC is also twice as much as the output. This is the oscilloscope waveform.The yellow is the signal input in the VIN_P and VIN_P_SEC,the blue one is the output.
I can't explain this phenomenon. I would be grateful if anyone could help me solve this problem.
