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Message ID: 2374     Entry time: Tue Jul 23 21:02:14 2019
Author: Shalika Singh 
Type: DailyProgress 
Category: 2micronLasers 
Subject: Transfer Function using SR785 spectrum analyzer 

The transfer function of the circuit was analyzed.

Attachment 1: The circuit diagramThe usual transimpedance configuration was made using the OP27 IC. There are two TIA as we will be using two PD in our final circuit. The two TIA are connected to Whitening Filter respectively. The Whitening filter has a gain of 10. Apart from that, the output of the two TIA is connected to a differential circuit and whose output is in turn connected to another independent whitening filter.

Attachment 2: The Transfer Function

The transfer function of the transimpedance amplifier, Differential Circuit(at both its input nodes), Whitening Filter was analyzed by using the SR785 spectrum analyzer. A 1V source was applied at the input of the respective circuit under consideration. 

**A 1k resistor was kept in series with every node which was given a source of 1V.

The terminology used in the graph:

TIA- Transfer function of the transimpedance amplifier

Differential at node1- TF of Differential circuit by providing source at node1

Differential at node2- TF of Differential circuit by providing source at node2

Whitening Filter- TF of Whitening filter by providing source at node1

TIA and Whitening filter- TF of transimpedance amplifier in series with the Whitening filter, and the source were at node1 of the TIA.


Attachment 1: full_circuit.pdf  251 kB  Uploaded Tue Jul 23 22:16:09 2019  | Show | Hide all | Show all
Attachment 2: Transfer_Function_of_Circuit.pdf  36 kB  Uploaded Tue Jul 23 22:29:54 2019  | Hide | Hide all | Show all
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