Can anyone recommend an integrator op amp?

[ElecTec]

Hi,

I'm building an integrator using an op-amp to integrate 15 volt 65nS pulses at a repetition rate of 100Khz using a 20uS time constant.

Can anyone recommend a suitable op-amp for this application. It needs to have very low input bias current to minimise d.c. drift and have sufficient bandwidth. The cost is not important but it needs to be readily available.

Many Thanks.

Paul.

 

[berkeman]

No opamp is going to respond to 65ns pulses. Can you say more about what you are trying to do? We may still be able to suggest some ways to accomplish what you want.

 

[ElecTec]

Hi,

Thanks for replying to my query.

The input pulse is gaussian in shape and 65nS wide. Taking this as approximating to half a sine wave I calculated the periodic time to be 130nS. This is a frequency of 7.69Mhz and I thought I would be able to get a suitable op amp with that bandwidth and low input current.

Any suggestions?

Regards,

Paul.

 

[edmondng]

how low input bias, is pA standard? just use a regular op amp should work
do a search at digikey compare.
TLC27M2AID has 1pA input bias current, bandwidth 800MHz

 

[unplebeian]

Look for something on TI that has a high GBW (gain bandwidth product)