Hello,
I am looking to design a transimpedance amplifier for use with an avalanche photodiode in a battery powered application and was hoping to get some assistance.
I am looking to detect pulsed light in the range of 800nm. I understand that a high speed op-amp would be required due to the nature of light, but am very unsure of what I need. I was looking at the OPA684 due to its slew rate of 820 V/us, but from what I've researched, a low bias current is very beneficial. Having a low bias current op amp reduces voltage offset and helps achieve the highest sensitivity. The OPA128 has a very low bias current but also a very average slew rate. I am also unsure of what the bandwidth range should be for such a device.
Also, how does one go about choosing the right value for the feedback resistance?
Any assistance or guidance on what parameters I should consider when choosing the right op-amp for such an application (APD transimpedance amplifier) would be greatly appreciated.
Thanks for your help.
-Joel Yello