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Entry  Wed Apr 7 10:48:04 2010, Alberto, Update, Electronics, REFL11 Noise Simulation rfpd11_testinput_noiseplot.pdf
    Reply  Wed Apr 7 10:58:15 2010, Koji, Update, Electronics, REFL11 Noise Simulation 
       Reply  Wed Apr 7 11:11:19 2010, Alberto, Update, Electronics, REFL11 Noise Simulation rfpd11_testinput_noiseplot.pdf
Message ID: 2781     Entry time: Wed Apr 7 11:11:19 2010     In reply to: 2780
Author: Alberto 
Type: Update 
Category: Electronics 
Subject: REFL11 Noise Simulation 

Quote:

What??? I don't see any gray trace of Rs in the plot. What are you talking about?

Anyway, if you are true, the circuit is bad as the noise should only be dominated by the thermal noise of the resonant circuit.

Quote:
LISO simulations confirm the estimate of ~15nV for the noise of REFL11.
The largest contribution comes from the output resistor (Rs in the schematic below).
See attached plot.

 

The colors in the plot were misleading.
Here's hopefully a better plot.
The dominant sources of noise are the resonant of the photodiode (~10Ohm), the max4107, the resistor in series to ground at the - input of the max4107.
Attachment 1: rfpd11_testinput_noiseplot.pdf  11 kB  | Hide | Hide all
rfpd11_testinput_noiseplot.pdf
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