Other Parts Discussed in Thread: OPA1652, OPA1662
Hi.
I have problems with the bias voltage of a buffer circuit.
I can´t manage to make the bias Vin/2. My supply is 5V. And I have tried to adjust R2 with a higher value,
but even with 5V out of the voltage divider the bias voltage won´t go over 2.1V. (See att.)
What is wrong with the circuit? Why is the input current so high? According to the datasheet the input bias current should be around 2pA.
I also tried with a input impedance of 470k (R3), but I still couldn´t get it over 2.2V.
Are there any problems with attenuating the output back to the voltage devider? I thought that would work as a virtual ground with sink/source capability.