Version 4 SHEET 1 2512 1036 WIRE 768 -256 160 -256 WIRE 1088 -256 768 -256 WIRE 1344 -256 1088 -256 WIRE 768 -224 768 -256 WIRE 1088 -160 1088 -256 WIRE 1344 -160 1344 -256 WIRE 768 -112 768 -144 WIRE 880 -112 768 -112 WIRE 1024 -112 960 -112 WIRE 768 -96 768 -112 WIRE 1184 -64 1088 -64 WIRE 304 -16 288 -16 WIRE 512 -16 304 -16 WIRE 624 16 608 16 WIRE 1184 16 1184 -64 WIRE 1184 16 704 16 WIRE 512 32 512 -16 WIRE 1184 32 1184 16 WIRE 160 64 160 -256 WIRE 288 64 288 -16 WIRE 1344 64 1344 -80 WIRE 1440 64 1344 64 WIRE 1344 96 1344 64 WIRE 768 112 768 -16 WIRE 512 144 512 112 WIRE 512 144 448 144 WIRE 608 144 608 16 WIRE 608 144 512 144 WIRE 736 144 608 144 WIRE 1184 144 1184 112 WIRE 1280 144 1184 144 WIRE 512 160 512 144 WIRE 1184 160 1184 144 WIRE 160 176 160 144 WIRE 288 176 288 144 WIRE 512 272 512 240 WIRE 768 272 768 176 WIRE 768 272 512 272 WIRE 1184 272 1184 240 WIRE 1184 272 768 272 WIRE 1344 272 1344 192 WIRE 1344 272 1184 272 WIRE 512 288 512 272 FLAG 512 288 0 FLAG 288 176 0 FLAG 304 -16 IN FLAG 1440 64 OUT FLAG 160 176 0 FLAG 448 144 VREF FLAG 1184 -64 IN_ SYMBOL res 496 144 R0 SYMATTR InstName R4 SYMATTR Value 4k7 SYMBOL res 496 16 R0 SYMATTR InstName R7 SYMATTR Value 25k SYMBOL voltage 288 48 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 WINDOW 3 -80 166 Left 2 SYMATTR Value PWL(0 0 1 24 2 0) SYMATTR InstName V1 SYMBOL voltage 160 48 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 5V SYMBOL res 1328 -176 R0 SYMATTR InstName R2 SYMATTR Value 4.7k SYMBOL npn 1280 96 R0 SYMATTR InstName Q1 SYMATTR Value BC847C SYMBOL TL431 768 144 M0 SYMATTR InstName U1 SYMATTR Value TL431 SYMBOL res 1168 144 R0 SYMATTR InstName R5 SYMATTR Value 4.7k SYMBOL res 1168 16 R0 SYMATTR InstName R6 SYMATTR Value 4.7k SYMBOL res 752 -240 R0 SYMATTR InstName R8 SYMATTR Value 220 SYMBOL res 720 0 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R3 SYMATTR Value 470k SYMBOL res 752 -112 R0 SYMATTR InstName R1 SYMATTR Value 220 SYMBOL pnp 1024 -64 M180 SYMATTR InstName Q2 SYMATTR Value BC857C SYMBOL res 864 -96 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R9 SYMATTR Value 4.7k TEXT 136 296 Left 2 !.tran 0 2 0 100u TEXT 128 432 Left 2 !*******************************************************************\n** Released by: Analog eLab Design Center, Texas Instruments Inc.\n* Part: TL431\n* Date: 12/14/2009\n* Model Type: Transient and AC\n*******************************************************************\n.SUBCKT TL431 7 6 11\n* K A FDBK\nV1 1 6 2.495\nR1 6 2 15.6\nC1 2 6 .5U\nR2 2 3 100\nC2 3 4 .08U\nR3 4 6 10\nGB1 6 8 VALUE = {IF(V(3,6)< 0 , 1.73*V(3,6) -1U , -1U)}\nD1 5 8 DCLAMP\nD2 7 8 DCLAMP\nV4 5 6 2\nG1 6 2 1 11 0.11\n.MODEL DCLAMP D (IS=13.5N RS=25M N=1.59\n+ CJO=45P VJ=.75 M=.302 TT=50.4N BV=34V IBV=1MA)\n.ENDS TEXT 136 344 Left 2 ;.step param Rhyst list 100K 200K 500k 1Meg