I did some additional voltage-measurements at PIN 17 (PA7) that is the ADC for Current measuerement.
Here are the results:
Current Voltage at PA7
0.000 A 0.0000 V
0.104 A 0.0001 V
0.203 A 0.0066 V
0.501 A 0.0404 V
1.003 A 0.0991 V
2.000 A 0.2167 V
5.519 A 0.6309 V
Looks like there is a problem with the OpAmp SGM8582 rather than with the ADC of the STM32.
What do you think?