Other Parts Discussed in Thread: TLV314
Below is LM258 SCH. We can see, if it work, LM258 U1 is output 0.5V. But actually it output 0.53V. When remove R492, it output=0.5V normally.
Keeping R392 in the board, I let U2 , U3 and U4 change the Gain resistance from 3KΩ / 15KΩ to 10KΩ / 50KΩ. After that U1 output 0.5V normally. May I know why?