LT SPICE, Show Command

Discussion in 'General Electronics Chat' started by BTSP, Sep 29, 2013.

  1. BTSP

    Thread Starter New Member

    Sep 29, 2013
    15
    0
    I am creating a netlist for LTSpice.
    When doing the simulation i want to see the parameters of the diode, dynamic resistance and such. Can i use the show command to do this? i am not sure how. i tried searching the forum, couldn't find anything.

    ***ANALOG ASS#1 CIRCUIT 1 ***

    *AC SOURCE
    vs 4 0 dc 0V ac 500mV

    *DC Biasing
    vcc 1 0 5V

    *Resistors
    Ra 2 3 10k
    R1 1 2 2K
    R2 5 0 2K
    RL 6 0 100

    *Capacitors
    Ci 4 3 16nF
    Co 5 6 16nF

    *Diode
    D1 3 5 diode1


    .model diode1 d (is=0.1pA n=1)
    show d1 [:]
    .op
    .end

    Thanks in advance
     
  2. upopads

    Active Member

    Dec 18, 2007
    42
    0
    I'm somewhat certain that if you don't specify those advanced values, they are zero.
     
  3. upopads

    Active Member

    Dec 18, 2007
    42
    0
    OK, no it is not. but here are all the default parameters for a diode
     
  4. upopads

    Active Member

    Dec 18, 2007
    42
    0
    So actually uh, yes it does look like the default value for ohmic resistance is 0.
     
  5. BTSP

    Thread Starter New Member

    Sep 29, 2013
    15
    0
    perfect, that helps. Thank you
     
  6. crutschow

    Expert

    Mar 14, 2008
    13,052
    3,244
    A diode will still have a dynamic resistance, even if the ohmic resistance is zero. It's cause by the logarithmic relation between current and the voltage forward drop. Here's a thread showing a simulation of the dynamic resistance (see Post #7). That resistance calculation is done from the simulation graphic display (see equation at top of graphic), not the netlist file.
     
Loading...