Application Note (AB-076 NOISE ANALYSIS OF FET TRANSIMPEDANCE AMPLIFIERS) Needs Update

This application note was carried over from Burr-Brown. The math involved in this application note needs to be checked.

1st).  Number from equation (9a) is inconsistant with number in equation(15a).

2nd). Figure 8) and Figure 9) needs to be checked

3rd). The procedure to calculate current noise is not quite clear (voltage noise part is okay)

Anybody tried to follow these procedure presented in this application note? 

3 Replies

  • Yi,

    Thank you for pointing these concerns out. We will be looking into this and correct for any errors as well as clarifications that need to be made. We appreciate your feedback.

    Best Regards,

    Chris Featherstone
    Linear Characterization Engineer
    High Performance Linear Products

  • In reply to Chris Featherstone:

    I agree with your assessment on Equation 9a and 15a.  Also the current section could use some clarification.  I will work on this, but this will take some time.  In the mean time below are some links to an alternative.  The articles below cover photo diode noise calculation, simulation, and measurement.  Let me know if this helps.

    Art  

     http://www.en-genius.net/includes/files/avt_120511.pdf

     http://www.en-genius.net/includes/files/avt_012312.pdf

     

    Art Kay Senior Applications Engineer High Performance Linear

  • In reply to Art Kay:

    Dear Art Kay,

    I am looking forward for your explainations regarding the application note of Burr-Brown. With the clarification for the analysis in the "Current Noise" section, this application note is a very good resource.

    I also have also a question about this application note:

    1) In equation (9), they use f_c = 100 Hz to calculate the E_n1,rms for region 1. The end point for region 1 is 673 Hz and not 100 Hz. Why do they use f_c = 100 Hz?

    Thank you very much. Kind regards,

    Mehmet