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Message ID: 2207     Entry time: Thu Jun 21 11:43:53 2018
Author: anchal 
Type: DailyProgress 
Category: ISS 
Subject: LISO Analysis of complete circuit 

I did TF, input impedance, opamp stability and noise analyses of the complete circuit with feedback part, modeled AOM (by phase shifter) and modeled Cavity (by LPF+NOT). Attached are the results. In the process, I completed wrapping some more LISO functions in python. We can do calculate input referred noise, input impedance, opamp stability and plot only dominant noise sources. The circuit schematic is attached and for now uses OP27. Next steps are to figure out what adjustments (components and values) can lower the noise. Opamps are in the stable region only.

Attachment 1: ISSAOMCavity.pdf  104 kB  Uploaded Thu Jun 21 12:56:35 2018  | Hide | Hide all
ISSAOMCavity.pdf
Attachment 2: ISSAOMCavityNoiseAnalysis.pdf  177 kB  Uploaded Thu Jun 21 12:56:56 2018  | Hide | Hide all
ISSAOMCavityNoiseAnalysis.pdf ISSAOMCavityNoiseAnalysis.pdf ISSAOMCavityNoiseAnalysis.pdf ISSAOMCavityNoiseAnalysis.pdf ISSAOMCavityNoiseAnalysis.pdf
Attachment 3: ISSAOMCavity.fil  834 Bytes  Uploaded Thu Jun 21 12:57:10 2018  | Hide | Hide all
r R14 510 OUT n1
c C7 1u n1 n2
c C4 470p n1 n4
r R15 560k n2 n4
r R16 560k n3 gnd
c C6 1u n3 gnd
op ISS2 op27 n3 n2 n4

r R18 1k n4 n5
c C8 4.7n n5 n7
... 41 more lines ...
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