Version 4
SHEET 1 1128 680
WIRE -272 -288 -368 -288
WIRE -144 -288 -272 -288
WIRE -16 -288 -144 -288
WIRE 80 -288 -16 -288
WIRE -272 -240 -272 -288
WIRE -144 -224 -144 -288
WIRE 80 -208 80 -288
WIRE -368 -96 -368 -288
WIRE -16 -96 -16 -288
WIRE -272 -80 -272 -160
WIRE -48 -80 -272 -80
WIRE 80 -64 80 -128
WIRE 80 -64 16 -64
WIRE 144 -64 80 -64
WIRE -144 -48 -144 -144
WIRE -112 -48 -144 -48
WIRE -80 -48 -112 -48
WIRE -48 -48 -80 -48
WIRE -272 -32 -272 -80
WIRE 144 -16 144 -64
WIRE -144 16 -144 -48
WIRE -80 16 -80 -48
WIRE 0 16 -80 16
WIRE 80 16 80 -64
WIRE -368 128 -368 -16
WIRE -368 128 -384 128
WIRE -272 128 -272 48
WIRE -272 128 -368 128
WIRE -144 128 -144 96
WIRE -144 128 -272 128
WIRE -16 128 -16 -32
WIRE -16 128 -144 128
WIRE 144 128 144 64
WIRE 144 128 -16 128
FLAG -384 128 0
FLAG 144 -64 Ua
FLAG -368 -288 Ue
FLAG -272 -80 Uptc
FLAG -112 -48 Uref
FLAG -368 -352 0
FLAG -368 -432 t
SYMBOL res -160 -240 R0
SYMATTR InstName R1
SYMATTR Value 68163
SYMBOL res -160 0 R0
SYMATTR InstName R4
SYMATTR Value 100437
SYMBOL voltage -368 -112 R0
WINDOW 123 0 0 Left 2
WINDOW 39 24 124 Left 2
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL Opamps\\opamp2 -16 -128 R0
SYMATTR InstName U1
SYMATTR Value LM239
SYMATTR SpiceModel LM239
SYMBOL res 64 -224 R0
SYMATTR InstName R5
SYMATTR Value 1k
SYMBOL res 96 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 100k
SYMBOL res -288 -256 R0
WINDOW 3 10 -51 Left 2
SYMATTR Value R=ntc(V(t), r_ref, t_ref, beta)
SYMATTR InstName R2
SYMBOL res -288 -48 R0
WINDOW 3 32 72 Left 2
SYMATTR Value 100k
SYMATTR InstName R3
SYMBOL voltage -368 -448 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value PULSE({tmin} {tmax} 0 {per/2} {per/2} 0 {per})
TEXT -408 -528 Left 2 !.inc LM239.mod
TEXT -408 -544 Left 2 !.tran {per}
TEXT -408 -512 Left 2 !.func ntc(t_act, r_ref, t_ref, beta)=r_ref*exp(beta*(1/(t_act-kelvin)-1/(t_ref-kelvin)))
TEXT -408 -480 Left 2 !.param per=100m tmin=0 tmax=100
TEXT -408 -464 Left 2 !.param r_ref=470k t_ref=25 beta=5000