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Entry  Wed Aug 1 11:16:22 2018, anchal, DailyProgress, ISS, Final Design for ISS Servo v3.2 Cryo_ISS3_2schematic.pdfCryo_ISS3_2_LISO_Analysis.pdfCryo_ISS3_1_ISS1_Optimization.pdf
    Reply  Wed Aug 1 17:31:19 2018, awade, DailyProgress, ISS, Final Design for ISS Servo v3.2 
       Reply  Sat Aug 4 21:37:55 2018, johannes, DailyProgress, ISS, Final Design for ISS Servo v3.2 
       Reply  Mon Aug 6 15:02:57 2018, anchal, DailyProgress, ISS, Final Design for ISS Servo v3.2 
Message ID: 2224     Entry time: Sat Aug 4 21:37:55 2018     In reply to: 2223
Author: johannes 
Type: DailyProgress 
Category: ISS 
Subject: Final Design for ISS Servo v3.2 

These are some "low-noise" FET input OpAmps which are all still alive:

  • MAX4475
  • AD8655
  • LT1792

not exact substitutes for AD743 but lower noise of all alternatives that I've come across so far.

 

Quote:

AD743 is discontinued.  We have a few in stock, and there are still a few SOIC-16 version that you can buy. 

But better to design with a op amp that is replaceable into the future.

Quote:

I checked with some replacements of opamp at stage 1 to reduce the noise due to current noise. It seems AD743 is the best balanced opamp for this location. Attached is the circuit schematic of this final version v3.2 , with LISO analysis and also the analysis done to reach to this opamp.

 

 

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