Version 4
SHEET 1 2308 1056
WIRE 464 -464 336 -464
WIRE 656 -464 464 -464
WIRE 880 -464 656 -464
WIRE 336 -432 336 -464
WIRE 656 -336 656 -464
WIRE 336 -256 336 -352
WIRE 464 -128 464 -464
WIRE 464 -128 256 -128
WIRE 656 -128 656 -256
WIRE 768 -128 656 -128
WIRE 656 -112 656 -128
WIRE 880 -112 880 -464
WIRE 768 -64 768 -128
WIRE 768 -64 720 -64
WIRE 816 -64 768 -64
WIRE 256 0 256 -128
WIRE 800 32 400 32
WIRE -208 80 -272 80
WIRE -160 80 -208 80
WIRE -16 80 -80 80
WIRE 16 80 -16 80
WIRE -272 112 -272 80
WIRE 464 144 464 -128
WIRE -16 160 -16 80
WIRE 48 160 -16 160
WIRE 256 160 256 80
WIRE 256 160 112 160
WIRE 400 160 400 32
WIRE 432 160 400 160
WIRE 624 176 496 176
WIRE 656 176 656 -16
WIRE 656 176 624 176
WIRE 800 176 800 32
WIRE 880 176 880 -16
WIRE 880 176 800 176
WIRE 912 176 880 176
WIRE 1072 176 912 176
WIRE 1536 176 1136 176
WIRE 1648 176 1536 176
WIRE 256 192 256 160
WIRE 432 192 256 192
WIRE 1536 208 1536 176
WIRE -272 224 -272 192
WIRE 256 304 256 192
WIRE 1536 320 1536 288
WIRE 656 368 656 176
WIRE 880 368 880 176
WIRE 768 416 720 416
WIRE 816 416 768 416
WIRE 656 480 656 464
WIRE 768 480 768 416
WIRE 768 480 656 480
WIRE 256 512 256 384
WIRE 464 512 464 208
WIRE 464 512 256 512
WIRE 656 576 656 480
WIRE 464 768 464 512
WIRE 464 768 336 768
WIRE 656 768 656 656
WIRE 656 768 464 768
WIRE 880 768 880 464
WIRE 880 768 656 768
WIRE 336 800 336 768
WIRE 336 976 336 880
FLAG 1536 320 0
FLAG -272 224 0
FLAG 336 -256 0
FLAG 16 80 IN
FLAG -208 80 Vo
FLAG 1648 176 OUT
FLAG 624 176 Q12
FLAG 912 176 Q34
FLAG 336 976 0
SYMBOL voltage -272 96 R0
WINDOW 123 0 0 Left 0
WINDOW 39 24 132 Left 0
SYMATTR InstName Vgen
SYMATTR Value SINE(0 0.2 60e3)
SYMBOL voltage 336 -448 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vsupply
SYMATTR Value 4
SYMBOL res -64 64 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R101
SYMATTR Value 50
SYMBOL pnp 816 464 M180
WINDOW 0 83 66 Left 0
WINDOW 3 82 40 Left 0
SYMATTR InstName Q4
SYMATTR Value {QP1}
SYMBOL pnp 720 464 R180
WINDOW 0 108 62 Left 0
WINDOW 3 72 33 Left 0
SYMATTR InstName Q2
SYMATTR Value {QP1}
SYMBOL npn 816 -112 R0
WINDOW 0 80 32 Left 0
WINDOW 3 81 61 Left 0
SYMATTR InstName Q3
SYMATTR Value {QN1}
SYMBOL npn 720 -112 M0
WINDOW 0 104 32 Left 0
WINDOW 3 67 63 Left 0
SYMATTR InstName Q1
SYMATTR Value {QN1}
SYMBOL res 640 -352 R0
SYMATTR InstName R1
SYMATTR Value {RN1}
SYMBOL res 640 560 R0
SYMATTR InstName R2
SYMATTR Value {RN1}
SYMBOL res 1520 192 R0
SYMATTR InstName R3
SYMATTR Value 3
SYMBOL cap 48 176 R270
WINDOW 0 32 32 VTop 0
WINDOW 3 0 32 VBottom 0
SYMATTR InstName C1
SYMATTR Value 47n
SYMBOL voltage 336 784 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vsupply1
SYMATTR Value -4
SYMBOL cap 1072 192 R270
WINDOW 0 32 32 VTop 0
WINDOW 3 0 32 VBottom 0
SYMATTR InstName C2
SYMATTR Value 470µ
SYMBOL Opamps\\UniversalOpamp2 464 176 R0
SYMATTR InstName U1
SYMBOL res 240 -16 R0
SYMATTR InstName R8
SYMATTR Value 1K
SYMBOL res 240 288 R0
SYMATTR InstName R9
SYMATTR Value 1K
TEXT 1248 -320 Left 0 !.tran 0 {1m+50u} 1m
TEXT 1256 -232 Left 0 !.param RN1=1K
TEXT 144 632 Left 0 ;optional buffer amp
TEXT 1480 -232 Left 0 ;I(limit)=470mA
TEXT 1256 -184 Left 0 !.model QN1 ako:2N4401
TEXT 1256 -144 Left 0 !.model QP1 ako:2N4403
RECTANGLE Normal 544 608 144 -160