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Entry  Wed Feb 20 23:25:50 2013, Zach, Summary, Electronics, Replacement for the AD743: OPA140 and OPA827 ULN_opamp_comparison_2_20_13.png
    Reply  Sat Feb 23 18:01:38 2013, Zach, Summary, Electronics, Replacement for the AD743: OPA140 and OPA827 OPA140_OPA827_noise_vs_Rs.pngScreen_Shot_2013-02-24_at_12.12.23_PM.pngScreen_Shot_2013-02-24_at_12.12.43_PM.png
       Reply  Sun Feb 24 16:49:00 2013, rana, Summary, Electronics, Replacement for the AD743: OPA140 and OPA827 
Message ID: 8153     Entry time: Sun Feb 24 16:49:00 2013     In reply to: 8151
Author: rana 
Type: Summary 
Category: Electronics 
Subject: Replacement for the AD743: OPA140 and OPA827 

  This looks pretty good already. Not sure if we can even measure anything reasonable below 0.1 Hz without a lot of thermal shielding.

The 10-20 kHz oscillation may just be the loop shape of the opamp. I think you saw similar effects when using the AD743 with high impedance for the OSEM testing.

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