OP296 input resistance

Mateo,

   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,

ADA4096-2.

Harry

Hello,

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.

Best regards,

Reinhard

This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

Thank you,
EZ Admin