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Entry  Wed Aug 28 21:25:20 2019, Shalika Singh, Noise Budget, 2micronLasers, Noise Bump observed at 8kHz during TIA noise analysis circuit.jpgcircuit_setup.jpgNoise_across_TIA_op27.pdfNoise_across_TIA_LT1792.pdfTIA.zip
    Reply  Thu Aug 29 15:36:49 2019, Koji, Noise Budget, 2micronLasers, Noise Bump observed at 8kHz during TIA noise analysis 
Message ID: 2412     Entry time: Thu Aug 29 15:36:49 2019     In reply to: 2411
Author: Koji 
Type: Noise Budget 
Category: 2micronLasers 
Subject: Noise Bump observed at 8kHz during TIA noise analysis 

You need to check the voltage noise of the regulator outputs with the opamps connected. Probably you did it. If so, it is a riddle why the 8kHz bump is not observed in the regulator outputs, but is in the opamp outputs...

Does the noise bump happen with the +/-15V supplied by 7815/7915? How about to change the capacitor values for LM317/337 to the ones recommended in the data sheet?

It is great to see the noise peaks were largely reduced by LT1792. This is what I found before although I can't explain why.

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