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[ZR431L]
*ZETEX ZR431L Spice Model v1.0 Last Revised 21/10/05
    *
    *NOTE: This is a simplified model.  Do not rely on this model for 
    *validation of circuit stability.  It does not accurately replicate 
    *stability boundary conditions when the device is operated with 
    *additional load capacitance.  Check the circuit stability by normal 
    *breadboarding techniques.
    *
    .SUBCKT ZR431L 1 2 3
    *Connections  Vz Vref Gnd
    *
    *Input current
    Rin 2 3 Rmod1 1.127E7
    D1 3 2 Dmod1
    D2 2 1 Dmod1
    Cin 2 3 10E-12
    *
    *Quiescent current
    E1 50 3 2 3 1
    D8 50 51 Dmod1
    Rq 51 52 Rmod4 31E3
    Vq 52 3 0
    F1 1 3 Vq 1
    Ro 1 3 1.5E6
    *
    *Reference voltage
    Iref 3 21 1.2405E-3
    Rref 21 3 Rmod2 1000
    *
    *Voltage dependence
    G1 21 3 POLY(1) 1 3 0 1.57E-6 -0.97e-7
    *
    *Gain
    G2 3 31 2 21 1e-7
    Rt2  3 31 100E6
    Rt3  3 32 3E6
    Ct1 31 32 3E-13
    D3 31 3  Dmod1
    D4 3 31  Dmod1
    *
    *Output
    *Q1 5 42 3 Qmod1
    Cr1 7 31 1.5e-14
    G3 41 3 31 3 0.8
    Rc1 6 7 5
    Rc2 7 5 5
    D6 3 41 Dmod1
    D7 3 1 Dmod1
    L1 1 6 10nH
    D9 5 41 Dmod2
    *
    .MODEL Qmod1 NPN BF=220 CJC=3E-12 CJE=3E-12
    .MODEL Rmod1 RES (TC1=2.95E-3 TC2=-5E-7)
    .MODEL Rmod2 RES (TC1=1.5e-5 TC2=-3.5e-7)
    .MODEL Rmod3 RES (TC1=-2.5E-3 TC2=2E-5)
    .MODEL Rmod4 RES (TC1=1.7E-3 TC2=0)
    .MODEL Dmod1 D IS=5E-15 RS=4 BV=22
    .MODEL Dmod2 D IS=1E-18 RS=.01
    .ENDS  ZR431L
    *
    *$
    *

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