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Entry  Sun Apr 10 19:14:08 2011, Koji, Update, Green Locking, New Green PD test1 SGD444A_240.pngSGD444A_240_test.png
    Reply  Mon Apr 11 09:49:53 2011, rana, Update, Electronics, New Green PD test1 
       Reply  Mon Apr 11 11:34:05 2011, Koji, Update, Electronics, New Green PD test1 SGD444A_240_test.png
          Reply  Mon Apr 11 21:13:15 2011, Koji, Update, Electronics, New Green PD test1 
Message ID: 4513     Entry time: Mon Apr 11 21:13:15 2011     In reply to: 4508
Author: Koji 
Type: Update 
Category: Electronics 
Subject: New Green PD test1 

Correction:

The (-) input has been decoupled by the capacitor. So the series resistance of the PD is not the matter.
In this sense, we should use 0Ohm for the (+) input shunting.

Quote:

51 Ohm for CLC409

The datasheet of CLC409 uses 25Ohm there. This is to cancel the input bias current of the two inputs of the opamp.

The source impedance (series) of SGD444 is 50Ohm. So I used 50Ohm for the + input shunting.

However, I could probably use anything between 0-50Ohm as the datasheet itself tells that the bias currents are
not related between the two inputs. In addition, I am not sure how much the real series resistance of the PD is.

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