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Message ID: 2390     Entry time: Mon Aug 12 11:37:36 2019
Author: Shalika Singh 
Type: Noise Budget 
Category: 2micronLasers 
Subject: Noise Analysis of Circuit using SR785 Spectrum Analyser and Zero Simulation 

Referring to elog entry 2385. I did the measurements again because mistakingly I had been using the SR560 with it's AC supply on. This time I used the 12V supply with no connection to the AC supply.

Attachment 1: The Circuit Diagram TIA

>>  the TIA with a gain of 5.1k

Attachment 2: Input Referred noise of TIA 

The input-referred current noise across the TIA was measured using SR785 and was compared against the graph obtained from ZERO simulation.

Attachment 3: Differential Circuit

>> gain of 100

Attachment 4: Input Referred noise of Differential Circuit

The input-referred voltage noise measured using SR785 and was compared against the graph obtained from ZERO simulation. 

Attachment 5: Whitening Filter Circuit

>> gain of 10

Attachment 6: Input Referred noise of Whitening Filter Circuit

The input-referred voltage noise was measured using SR785 and was compared against the graph obtained from ZERO simulation.

Attachment 7: The Scripts

All the scripts and data used in the measurement.

** I did notice a reduction in 60Hz harmonics but I still see a deviation from simulated results at higher frequencies and at frequencies below 10Hz.

Attachment 1: TIA.png  18 kB  Uploaded Mon Aug 12 12:42:05 2019  | Hide | Hide all
TIA.png
Attachment 2: Noise_across_TIA.pdf  86 kB  Uploaded Mon Aug 12 12:42:45 2019  | Hide | Hide all
Noise_across_TIA.pdf
Attachment 3: Differential_Circuit.png  25 kB  Uploaded Mon Aug 12 12:43:07 2019  | Hide | Hide all
Differential_Circuit.png
Attachment 4: Noise_across_Differential_Circuit.pdf  88 kB  Uploaded Mon Aug 12 12:43:21 2019  | Hide | Hide all
Noise_across_Differential_Circuit.pdf
Attachment 5: Whitening_Filter.png  27 kB  Uploaded Mon Aug 12 12:44:49 2019  | Hide | Hide all
Whitening_Filter.png
Attachment 6: Noise_across_Whitening_Filter.pdf  87 kB  Uploaded Mon Aug 12 12:45:07 2019  | Hide | Hide all
Noise_across_Whitening_Filter.pdf
Attachment 7: Noise.zip  670 kB  Uploaded Thu Aug 15 23:06:29 2019
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