RE: What you need to know about transimpedance amplifiers – part 1

Michael Steffes — Sun, 17 Jan 2021 16:04:42 GMT

This post is referred to by the latest decomp parts for transimpedance design - it gives the correct Cf solution for a butterworth design including the 0.707 term. The added resources though. The first is the the one by Xavier Ramus from my original work and I am sure it is correct. However the 4th reference on choosing the best amplifier by Hooman repeats a common error in setting the Cf - essentially targeting the feedback pole at the Fo frequency - this will give you a closed loop Q=1 peaking, where as the correct equation gives you butterworth. Might want to edit that older app note by Hooman or remove it.

RE: What you need to know about transimpedance amplifiers – part 1

aditya chowdary tella — Fri, 18 Nov 2016 15:31:28 GMT

Hi,

Could you explain the following

1) Why the source resistance is not considered while calculating the loop gain or Noise gain

2) Can the differential input capacitance be neglected due to virtual ground behavior as explained in your previous post ?