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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: 7927     Entry time: Tue Jan 22 19:51:52 2013     In reply to: 7926     Reply to this: 7929
Author: Koji 
Type: Update 
Subject: Photodiode transimpedance 

- The data should be plotted in a log-log scale.
- The data points were only taken in the high current region.

- The plot may suggest that the amplifier saturate at the RF.

PDA255 has the nomial transimpedance gain of 10^4 Ohm.
The DC current of 10^-3 gives the output of 10V.
This plot may tell that the saturation starts even at the 1/10 of the full DC range.

The plot doesn't have many points below 0.1mA.
Consult with my plots for the similar measurements.
The measured points are logarithmically spaced. Use the same technique.

- It is also very unknown that how the noise level is calculated. No info is supplied in the plot or the elogs.

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