Version 4 SHEET 1 5352 1764 WIRE 4304 -176 4288 -176 WIRE 4352 -176 4304 -176 WIRE 4208 -112 4192 -112 WIRE 4304 -112 4304 -176 WIRE 4304 -112 4272 -112 WIRE 4368 -112 4304 -112 WIRE 4704 -112 4704 -128 WIRE 4752 -112 4704 -112 WIRE 4880 -112 4832 -112 WIRE 4368 -80 4368 -112 WIRE 3360 -48 3200 -48 WIRE 4704 0 4704 -112 WIRE 4752 0 4704 0 WIRE 4880 16 4880 -112 WIRE 4880 16 4816 16 WIRE 5072 16 4880 16 WIRE 3200 32 3200 -48 WIRE 3232 32 3200 32 WIRE 4752 32 4720 32 WIRE 5072 32 5072 16 WIRE 5072 32 5056 32 WIRE 3360 48 3360 -48 WIRE 3360 48 3296 48 WIRE 3872 48 3360 48 WIRE 3968 48 3968 16 WIRE 3968 48 3872 48 WIRE 4368 48 4368 0 WIRE 4480 48 4368 48 WIRE 4608 48 4608 32 WIRE 4608 48 4544 48 WIRE 4720 48 4720 32 WIRE 4720 48 4608 48 WIRE 2768 64 2640 64 WIRE 2960 64 2960 0 WIRE 2960 64 2832 64 WIRE 3232 64 2960 64 WIRE 4608 64 4608 48 WIRE 4368 80 4368 48 WIRE 4784 80 4784 48 WIRE 3968 96 3968 48 WIRE 4192 96 4192 -112 WIRE 4192 96 3968 96 WIRE 4208 96 4192 96 WIRE 4320 96 4288 96 WIRE 5072 128 5072 96 WIRE 2960 144 2960 64 WIRE 4320 144 4320 96 WIRE 4320 144 4176 144 WIRE 3264 160 3264 80 WIRE 4176 192 4176 144 WIRE 4208 192 4176 192 WIRE 4320 192 4288 192 WIRE 4368 192 4368 160 WIRE 4368 192 4320 192 WIRE 4320 224 4320 192 WIRE 5072 224 5072 208 WIRE 5120 224 5072 224 WIRE 5072 240 5072 224 FLAG 3264 16 VCC FLAG 3520 480 0 FLAG 3520 400 VCC FLAG 2944 544 0 FLAG 2944 464 Vin FLAG 5056 32 Vout3 FLAG 4288 -256 0 FLAG 4320 288 0 FLAG 4352 -256 0 FLAG 2640 64 Vin FLAG 5072 320 0 FLAG 5120 224 Vout_final FLAG 3264 160 0 FLAG 2960 -80 VCC FLAG 2960 224 0 FLAG 4784 -16 VCC FLAG 3872 48 Vout2 FLAG 4784 80 0 FLAG 4608 -48 VCC FLAG 4608 144 0 FLAG 4704 -272 0 SYMBOL Opamps\\UniversalOpamp2 3264 48 R0 SYMATTR InstName U2 SYMBOL voltage 3520 384 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 9 SYMBOL voltage 2944 448 R0 WINDOW 123 24 124 Left 2 WINDOW 39 24 152 Left 2 SYMATTR Value2 AC 1 0 SYMATTR SpiceLine Rser=1Meg SYMATTR InstName V2 SYMATTR Value SINE(0 0.2 1k) SYMBOL res 4272 -272 R0 WINDOW 0 -82 40 Left 2 WINDOW 3 -66 76 Left 2 SYMATTR InstName Rhigh SYMATTR Value 24k SYMBOL res 4304 176 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName Rlow SYMATTR Value 24k SYMBOL cap 4304 224 R0 SYMATTR InstName Clow SYMATTR Value 0.022µ SYMBOL cap 4272 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName Chigh SYMATTR Value 5600p SYMBOL res 4352 -96 R0 SYMATTR InstName RPOT1 SYMATTR Value {Z} SYMBOL res 4352 64 R0 SYMATTR InstName RPOT2 SYMATTR Value {50k-Z} SYMBOL res 4336 -272 R0 SYMATTR InstName LDRhigh SYMATTR Value {X} SYMBOL res 4304 80 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName LDRlow SYMATTR Value {Y} SYMBOL cap 5056 32 R0 SYMATTR InstName C1 SYMATTR Value 10µ SYMBOL res 5056 112 R0 SYMATTR InstName RVol1 SYMATTR Value 500k SYMBOL res 5056 224 R0 SYMATTR InstName RVol2 SYMATTR Value 500k SYMBOL res 2944 -96 R0 SYMATTR InstName R3 SYMATTR Value 1Meg SYMBOL res 2944 128 R0 SYMATTR InstName R4 SYMATTR Value 1Meg SYMBOL cap 2832 48 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C3 SYMATTR Value 0.1µ SYMBOL Opamps\\UniversalOpamp2 4784 16 R0 SYMATTR InstName U3 SYMBOL res 4592 48 R0 SYMATTR InstName R7 SYMATTR Value 1Meg SYMBOL res 4592 -64 R0 SYMATTR InstName R8 SYMATTR Value 1Meg SYMBOL cap 4544 32 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C7 SYMATTR Value 10µ SYMBOL res 4720 -112 R180 WINDOW 0 36 76 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName R1 SYMATTR Value 1k SYMBOL res 4736 -96 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R2 SYMATTR Value 100k SYMBOL cap 4688 -272 R0 SYMATTR InstName C2 SYMATTR Value 0.1µ TEXT 3872 568 Left 2 !.step param X 3k 10k 1k TEXT 3888 400 Left 2 !.ac dec 10 1 1G TEXT 4712 -432 Left 2 ;f3db = 1 / (2*pi*Rpole*Cpole) TEXT 4664 -504 Left 2 ;Vout / Vin = (1 + (Rf / Rg)) * ( 1 / ( 1 + s*Rpole*Cpole) ) TEXT 4224 568 Left 2 !.step param Y 3k 10k 1k TEXT 3888 536 Left 2 !*.param X 3k TEXT 4232 528 Left 2 !*.param Y=3k TEXT 4584 520 Left 2 !.param Z=30k TEXT 4592 568 Left 2 !*.step param Z 1k 9.9k 1k TEXT 2016 736 Left 2 ;https://www.digikey.com/products/en/sensors-transducers/optical-sensors-photo-detectors-cds-cells/540?k=light+dependent+resistor&k=&pkeyword=light+dependent+resistor&sv=0&pv732=4&sf=0&quantity=&ColumnSort=0&page=1&stock=1&datasheet=1&pageSize=25 TEXT 4312 400 Left 2 !*.tran 0 50ms 0 1ms TEXT 4152 400 Left 2 !.op TEXT 2616 376 Left 2 ;*Important Note: Signal starts clipping at bottom if Rin < 50k