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Entry  Mon Jul 23 18:07:14 2018, anchal, DailyProgress, ISS, Introduced zero to cancel cavity pole. Mostly final circuit. CRYO_ISS2LoopGainTF.pdfCryo_ISS2_AOMCavity_Schematic.pdfCryo_ISS2_AOMCavity_LTSpiceAnalysis.zip
    Reply  Tue Jul 24 11:04:37 2018, johannes, DailyProgress, ISS, Introduced zero to cancel cavity pole. Mostly final circuit. 
       Reply  Tue Jul 24 14:28:08 2018, johannes, DailyProgress, ISS, Introduced zero to cancel cavity pole. Mostly final circuit. Cryo_ISS3_AOMCavity_Schematic.pdfCryo_ISS3_LISO_Analysis.pdfCRYO_ISS3AOMCavityLisoAnalysis.pdf
    Reply  Tue Jul 24 13:47:48 2018, anchal, DailyProgress, ISS, Introduced zero to cancel cavity pole. Mostly final circuit. Cryo_ISS2_LISO_Analysis.pdfCRYO_ISS2AOMCavityLisoAnalysis.pdf
Message ID: 2213     Entry time: Mon Jul 23 18:07:14 2018     Reply to this: 2214   2215
Author: anchal 
Type: DailyProgress 
Category: ISS 
Subject: Introduced zero to cancel cavity pole. Mostly final circuit. 

After discussion with Johannes, I added a zero near the cavity pole to neutralize its effect at higher frequencies. I also replaced the passive high frequency boost with an active one in stage 3. Attached is the new circuit schematic (Mostly final one as it looks good). Also attached are open loop transfer function from LTSpice.
Next steps are to do noise analysis and individual opamp stability analysis in LISO one last time.

Attachment 1: CRYO_ISS2LoopGainTF.pdf  25 kB  Uploaded Mon Jul 23 19:12:03 2018  | Hide | Hide all
CRYO_ISS2LoopGainTF.pdf
Attachment 2: Cryo_ISS2_AOMCavity_Schematic.pdf  110 kB  Uploaded Mon Jul 23 19:12:13 2018  | Hide | Hide all
Cryo_ISS2_AOMCavity_Schematic.pdf
Attachment 3: Cryo_ISS2_AOMCavity_LTSpiceAnalysis.zip  128 kB  Uploaded Mon Jul 23 19:12:22 2018
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