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Entry  Wed Jun 18 15:25:06 2014, Nichin, Update, Electronics, BBPD Transimepedence plot BBPD.pngBBPD_readings_06-18-2014.zip
    Reply  Wed Jun 18 16:44:55 2014, Manasa, Update, Electronics, BBPD installed for BEATX detection 
    Reply  Sat Jun 21 01:46:28 2014, Nichin, Update, Electronics, BBPD Transimepedence plot BBPD_06-18-2014.pdfBBPD_readings_06-18-2014.zip
Message ID: 10058     Entry time: Wed Jun 18 15:25:06 2014     Reply to this: 10059   10087
Author: Nichin 
Type: Update 
Category: Electronics 
Subject: BBPD Transimepedence plot 


To measure the transimpedence of  the Broadband photodiode (D1002969-v8), using a New focus photodiode (1611) as reference. The amplitude modulated Jenne Laser (1.2mW) was used @20mA

The steps involved in getting the transimpedence:

Acquiring data

  • The following conditions were set on Network Analyzer Agilent 4395:

1) Frequency sweep range: 500KHz to 300 MHz.

2) Number of Points sampled in  the range: 301

3) Type of sweep: Logarithmic

  • Set the NA to give the corresponding transfer function value (output of BBPD over output of 1611) and also Phase response in degrees.
  • Save the data into floppy disk for processing on the computer.


  • The matlab code attached (Trans_plot.m) will then give plots for the absolute values of transimpedence in V/A.
  • Logic involved in the code will be presented clearly in a separate Elog. 


The Plots of transimpedence obtained are attached. The data and matlab code used is in the zip file.

The transimpedence of  Broadband photodiode (D1002969-v8) was around 1200 - 1300 V/A for most of the range (2), but the value started falling as the frequency approached 200 MHz. 

Attachment 1: BBPD.png  27 kB  | Hide | Hide all
Attachment 2: BBPD_readings_06-18-2014.zip  9 kB
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