Hi, i would like to know the OP296 input resistance. I was wondering if the OP296 works as a transimpedance amplifier with a 1M feedback resistance (so i need that value). any advice?.
And the same question for ADA4528.
How were you going to use input resistance? It's generally of limited usefulness
and for a voltage follower, the input resistance is bootstrapped by the open loop gain
at that frequency. For error calculations, input bias current can be used.
I would not do a new design with the OP296 which came out in 1995. I would use the next generation,
the worst case input bias current of the OP296 is +-50nA, which you have to add or deduct from the current of your source (a photodiode, for example). Say, your photodiode sources 500nA then you expect 0.5V at the output of your opamp. In a worst case situation you will only get 0.45V or even 0.55V.
The input offset current is not included in the calculation.