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Entry  Tue Jan 22 17:29:29 2013, Riju, Update, , Photodiode transimpedance pda255shotnoiseintercept.pdf
    Reply  Tue Jan 22 19:51:52 2013, Koji, Update, , Photodiode transimpedance 
       Reply  Wed Jan 23 11:43:19 2013, Riju, Update, , Photodiode transimpedance pda255shotnoiseintercept1.pdf
Message ID: 7926     Entry time: Tue Jan 22 17:29:29 2013     Reply to this: 7927
Author: Riju 
Type: Update 
Subject: Photodiode transimpedance 


Summary:  I am stuck with the measurement of shot-noise-intercept-current of PDA255. Seeking help.

Motivation: It is to measure the shot noise intercept current for PDA255 - the MC transmission RF photodiode to get an idea for the noise current for the detector.

Method: It is as described in the elog  7907 

Result: The plot is attached here.

Discussion: The result I got is really unexpected, the noise voltage should increase with the DC current level that corresponds to the increment of light level too. But actually it is decreasing. Three times I have repeated this experiment and got the same result. I want some suggestion on this regard.

Attachment 1: pda255shotnoiseintercept.pdf  3 kB  | Hide | Hide all
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