Junction capacitance at 2.4 GHz

Discussion in 'General Electronics Chat' started by philm01, Jul 18, 2014.

  1. philm01

    Thread Starter Member

    Mar 22, 2014
    Hello everyone,

    I am in need of some help. I have a diode rectifing a 2.4 GHz signal and I need to perform impedance matching on it. Using pspice, I determined what the series resistance of the diode is. All I need to know is the junction capacitance at 2.4 GHz. My only problem is is that I do not know how to determine this from pspice. Would anyone be able to assist me on this matter? BTW, the diode part number is a 1N6263.

    Thank you
  2. crutschow


    Mar 14, 2008
    The junction capacitance likely does not change much with frequency. It's listed in the data sheet as 2pF at zero bias.

    That diode likely has too much capacitance to be useful at 2.4GHz. You need a diode specified for microwave applications.

    To measure the junction capacitance you apply a small AC voltage (say 1mV) to the unbiased diode and measure the current. From that and knowing the AC frequency you can calculate the junction capacitance.
    Last edited: Jul 18, 2014