Version 4 SHEET 1 880 680 WIRE 624 0 624 -16 WIRE 736 0 736 -16 WIRE 400 16 160 16 WIRE 416 16 400 16 WIRE 512 16 496 16 WIRE 224 64 224 48 WIRE 160 80 160 16 WIRE 192 80 160 80 WIRE 304 96 256 96 WIRE 400 96 400 16 WIRE 400 96 368 96 WIRE 624 96 624 80 WIRE 736 96 736 80 WIRE -48 112 -80 112 WIRE 80 112 32 112 WIRE 192 112 80 112 WIRE 560 112 432 112 WIRE 80 128 80 112 WIRE 432 160 432 112 WIRE 464 160 432 160 WIRE 560 176 560 112 WIRE 560 176 528 176 WIRE 576 176 560 176 WIRE 400 192 400 96 WIRE 464 192 400 192 WIRE 160 224 160 80 WIRE 192 224 160 224 WIRE 304 240 256 240 WIRE 400 240 400 192 WIRE 400 240 368 240 WIRE 96 256 48 256 WIRE 192 256 96 256 WIRE 48 272 48 256 WIRE 160 352 160 224 WIRE 192 352 160 352 WIRE 304 368 256 368 WIRE 400 368 400 240 WIRE 400 368 368 368 WIRE -48 384 -80 384 WIRE 80 384 32 384 WIRE 112 384 80 384 WIRE 192 384 112 384 WIRE 80 416 80 384 FLAG 80 208 0 FLAG 48 352 0 FLAG 624 96 0 FLAG 624 -16 V+ FLAG 224 48 V+ FLAG 224 208 V+ FLAG 80 112 Ref_High FLAG 576 176 Out IOPIN 576 176 Out FLAG 96 256 In FLAG 512 16 V+ FLAG 736 96 0 FLAG 736 -16 V- FLAG 224 128 V- FLAG 224 272 V- FLAG 496 144 V+ FLAG 496 208 V- FLAG -80 112 V+ FLAG 224 336 V+ FLAG 224 400 V- FLAG 80 496 0 FLAG -80 384 V- FLAG 112 384 Ref_Low SYMBOL Opamps\\LM324 224 32 R0 WINDOW 3 16 123 Left 2 SYMATTR InstName U1 SYMBOL Opamps\\LM324 224 176 R0 WINDOW 3 16 127 Left 2 SYMATTR InstName U2 SYMBOL diode 368 112 M270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value 1N4148 SYMBOL diode 368 256 M270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value 1N4148 SYMBOL battery 624 -16 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V3 SYMATTR Value 12V SYMBOL voltage 48 256 R0 WINDOW 3 -38 51 Right 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 WINDOW 0 38 56 Left 2 SYMATTR Value PULSE(-12 12 .5 1 1 .5 2 1) SYMATTR InstName V1 SYMBOL res 512 0 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R1 SYMATTR Value 10k SYMBOL battery 736 -16 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V4 SYMATTR Value -12V SYMBOL Opamps\\LM324 496 112 R0 WINDOW 3 16 127 Left 2 SYMATTR InstName U3 SYMBOL res 96 112 M0 SYMATTR InstName R4 SYMATTR Value 7.15K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL res -64 128 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R2 SYMATTR Value 10k SYMBOL Opamps\\LM324 224 304 R0 WINDOW 3 16 127 Left 2 SYMATTR InstName U4 SYMBOL diode 304 384 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D3 SYMATTR Value 1N4148 SYMBOL res 96 400 M0 SYMATTR InstName R3 SYMATTR Value 7.15K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL res -64 400 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R5 SYMATTR Value 10k TEXT 456 360 Left 2 !.tran 0 4 1m startup