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SPICE problem

Discussion in 'General Electronics' started by Robert Baer, Sep 7, 2003.

  1. Robert Baer

    Robert Baer Guest

    I have not found any models for the LM285-ADJ, so have attempted to
    create one, by following the equivalent circuit given in a data sheet.
    However, i cannot figure why it does not work.
    Please critique:
    VREF+MOSFET reg (25V ref)
    ..OPTIONS ACCT LIST NODE OPTS NUMDGT=6 RELTOL=0.00001 NOPAGE
    ..TEMP 25
    ..DC V1 -50 50 1
    V1 4 0 DC 180V ;Vreg
    R1 3 1 7.87MEG ;for Vref 25V appx
    R2 4 3 412K ;3uA at 1.24V
    VR 0 1 0.0V ; ground current sense
    * + FB -
    X3 4 3 1 LM285ADJ
    ..PRINT DC I(VR) V(3) V(4)
    ..PLOT DC I(VR) V(3) V(4)
    ..SUBCKT LM285ADJ 1 2 3 ; 1=+ cathode, 2=FB, 3=- anode
    ISINK 0 81 5UA
    RSINK 81 0 1E15 ; dummy - get +V term 81 rel term 0
    VREF 82 81 1.24V ; vary this +/- 1%
    VP 83 0 15V
    VN 84 0 -15V
    * C B E SUB
    Q1 82 85 0 0 QN2222
    RA 3 0 1E-6OHM
    RC 1 82 1E-6OHM
    X1 81 2 83 84 85 TL031
    ..ENDS LM285ADJ
    ..MODEL QN2222 NPN(
    + IS= 2.560E-14 BF= 200. NE= 2.00 IKF= .560
    + BR= 5.00 NC= 2.00 ISE= 1.280E-11
    + RB= 10.0 RC= .500 ISC= 1.280E-11
    + CJE= 2.500E-11 TF= 5.333E-10 CJC= 8.000E-12 TR= 4.000E-08)
    * TL031 operational amplifier "macromodel" subcircuit
    * n.i. input inverting input
    * | | positive power supply
    * | | | negative power supply
    * | | | | v--output
    ..subckt TL031 1 2 3 4 5
    c1 11 12 3.498E-12
    c2 6 7 15.00E-12
    css 10 99 11.38E-12
    dc 5 53 dx
    de 54 5 dx
    dlp 90 91 dx
    dln 92 90 dx
    dp 4 3 dx
    egnd 99 0 poly(2) (3,0) (4,0) 0 .5 .5
    fb 7 99 poly(5) vb vc ve vlp vln 0 936.5E3 -900E3 900E3 900E3
    -900E3
    ga 6 0 11 12 113.1E-6
    gcm 0 6 10 99 2.257E-9
    iss 3 10 dc 76.50E-6
    hlim 90 0 vlim 1K
    j1 11 2 10 jx
    j2 12 1 10 jx
    r2 6 9 100.0E3
    rd1 4 11 8.841E3
    rd2 4 12 8.841E3
    ro1 8 5 135
    ro2 7 99 135
    rp 3 4 138.5E3
    rss 10 99 2.614E6
    vb 9 0 dc 0
    vc 3 53 dc 1.700
    ve 54 4 dc 1.800
    vlim 7 8 dc 0
    vlp 91 0 dc 8
    vln 0 92 dc 8
    ..model dx D(Is=800.0E-18)
    ..model jx PJF(Is=1.000E-12 Beta=140e-6 Vto=-1)
    ..ends TL031
    ..END
     
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