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Convert TL431 to TLVH431 (Pspice)

What modifications are needed to convert C. Bassos TL431 Pspice model to a TLVH431 model?

I tried the obvious switching the 2.495V to 1.24V but I get a reference of 1.49V when I do this, it should be 1.24V.

I just bought fifty of these it would be nice to have a model for AC simulations.

.SUBCKT TL431 7 6 11 V1 1 6 2.495 R1 6 2 15.6 C1 2 6 .5U R2 2 3 100 C2 3 4 .08U R3 4 6 10 G2 6 8 3 6 1.73 D1 5 8 DC D2 7 8 DC V4 5 6 2 G1 6 2 1 11 0.11 .MODEL DC D

+IS=13.5N RS=25M N=1.59
  • CJO=45P VJ=.75 M=.302
  • TT=50.4N BV=34V IBV=1MA .ENDS
********

Thanks

Reply to
Hammy
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"Hammy" schrieb im Newsbeitrag news: snipped-for-privacy@4ax.com...

Hello

I had success sometimes in the past with the changes in the model below, but I can't remember the details.

Helmut

.SUBCKT TLV431 7 6 11 V1 1 6 1.24 R1 6 2 15.6 C1 2 6 .5U R2 2 3 100 C2 3 4 .08U R3 4 6 10 G2 6 8 3 6 0.86 D1 5 8 DC D2 7 8 DC V4 5 6 1.2 G1 6 2 1 11 0.11 .MODEL DC D

+IS=13.5N RS=25M N=1.59
  • CJO=45P VJ=.75 M=.302
  • TT=50.4N BV=34V IBV=1MA .ENDS
Reply to
Helmut Sennewald

Hello Helmut

I did some more looking and I found a model in C.Basso's second book "Switch-Mode Power Supplies Spice Simulations and Practical Designs". I haven't had too much of an opportunity to test it, but it does provide the correct reference.

This is the schematic that SUBCKT TL431 refers to:

formatting link

This is the .txt file

.SUBCKT TL431 a k ref C1 7 a 1n Q1 k 2 1 QN3904 R1 1 7 240 R2 7 a 6.6k Q2 k 7 a QN3904 50 D1 ref k D4mod D2 a k D2mod V1 5 a DC=2.49 D3 a 2 D3mod C4 k 2 43p G2 a 2 5 ref -250u

  • .MODEL QN3904 NPN AF=1.0 BF=300 BR=7.5 CJC=3.5PF CJE=4.5PF
  • IKF=.025 IS=1.4E-14 ISE=3E-13 KF=9E-16 NE=1.5 RC=2.4
  • TF=4E-10 TR=21E-9 VAF=100 XTB=1.5 .MODEL D3mod D N=0.01 .MODEL D2mod D BV=36 CJO=4PF IS=7E-09 M=.45 N=1.3 RS=40
  • TT=6E-09 VJ=.6V .MODEL D4mod D BV=100V CJO=4PF IS=7E-09 M=.45 N=2 RS=.8
  • TT=6E-09 VJ=.6V
  • .ENDS

He shows good agreement with most of the graphs in the TL431 data sheet.

I just changed the reference voltage (V15) to 1.24V. There doesn't seem to be any significant difference between the LV version and the standard version other then the REF voltage, bias current and max cathode voltage.

He uses this TL431 model all through his book for small signal simulations as well as DC transient for SMPS's.

Thanks for the response.

Reply to
Hammy

*******************************************
  • REFERENCE
  • | ANODE
  • | | CATHODE
  • | | | .SUBCKT TLV431AJ 1 2 3 V1 6 7 DC 1.4V I1 2 4 1E-3 R1 1 2 8.333E6 R2 4 2 RMOD 1.249K R3 5 7 .2 D1 3 6 DMOD1 D2 2 3 DMOD1 D3 2 7 DMOD2
*E1 5 2 POLY(2) (4,2) (1,2) 0 710 -710 E1 5 2 VALUE = {V(4,2)*710 + V(1,2)*-710} .MODEL RMOD RES (TC1=1.4E-5 TC2=-1E-6) .MODEL DMOD1 D (RS=.3) .MODEL DMOD2 D (RS=1E-6) .ENDS TLV431AJ *******************************************

...Jim Thompson

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| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
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Reply to
Jim Thompson

Thanks Jim

Reply to
Hammy

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