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Entry  Tue Mar 29 22:15:25 2011, tara, Notes, Electronics Equipment, RFPD bad connector rcavPD.pngacavPD.pngnoise_raw.pngRFPDnoise.png
    Reply  Wed Mar 30 20:23:58 2011, tara, Notes, Electronics Equipment, RFPD noise comparison D980454-00.pdfRFPDnoise.pngrfpd_psl.fil
       Reply  Thu Mar 31 19:37:54 2011, rana, Notes, Electronics Equipment, RFPD noise comparison 
          Reply  Fri Apr 1 02:18:13 2011, tara, Notes, Electronics Equipment, RFPD noise comparison 
Message ID: 557     Entry time: Wed Mar 30 20:23:58 2011     In reply to: 556     Reply to this: 558
Author: tara 
Type: Notes 
Category: Electronics Equipment 
Subject: RFPD noise comparison 

The RPFD noise is compared with LISO model. They are not exactly match, but their levels are not that far off, within a factor of 4.

The RFPDs should not have any serious problem.

*edited: 10 ohm for R_pd, 5.6pF for C39, 320nH for L8.



The current ACAV RFPD's schematic can be founded here. The components with "See table" comment can be found on the 2nd page of the attached file.

I based my model on ACAV RFPD's schematic and simulated the noise output.

There are certain parameters that I estimated

1) R and C of the PD, I use 10 ohm and 120 pF as of now.

2) C39 is 5.6 pF as written in the doc, this is for the 2w notch.

3) MAX4107ESA opamp is not included in liso library, so I use 4106 instead,

4) I'm not quite sure if C5 is currently in used or not, but it's not added in the model.

This is just an approximate comparison to see if the RPFD is bad or not. To get a more accurate result,

Rpd, Cpd and the components have to be measured.




Attachment 1: D980454-00.pdf  57 kB  Uploaded Wed Mar 30 21:32:09 2011  | Hide | Hide all
D980454-00.pdf D980454-00.pdf
Attachment 2: RFPDnoise.png  21 kB  Uploaded Fri Apr 1 03:15:40 2011  | Hide | Hide all
Attachment 3: rfpd_psl.fil  1 kB  Uploaded Fri Apr 1 03:18:50 2011  | Hide | Hide all
# Resonant RF diode front end

##      ACAV RFPD
##                            --C1--
#                            |      |                           |\
##          n1----------------L3--- n5 ---- C10 --- n7 -------- |  \
#           |      |      |            |             |          |4107ESA>-- n10 ---R6---no
... 60 more lines ...
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