Version 4
SHEET 1 1696 680
WIRE 128 -96 80 -96
WIRE 256 -96 128 -96
WIRE 528 -96 256 -96
WIRE 672 -96 608 -96
WIRE 704 -96 672 -96
WIRE 768 -96 704 -96
WIRE 1104 -96 848 -96
WIRE 256 -64 256 -96
WIRE 704 -64 704 -96
WIRE 256 32 256 0
WIRE 336 32 256 32
WIRE 448 32 416 32
WIRE 704 32 704 0
WIRE 256 64 256 32
WIRE 448 64 448 32
WIRE 176 144 176 128
WIRE -80 160 -176 160
WIRE 80 160 80 -96
WIRE 80 160 0 160
WIRE 144 160 80 160
WIRE 256 176 256 128
WIRE 256 176 208 176
WIRE 288 176 256 176
WIRE 304 176 288 176
WIRE 432 176 384 176
WIRE 496 176 432 176
WIRE 528 176 496 176
WIRE 656 176 528 176
WIRE 768 176 720 176
WIRE 912 176 832 176
WIRE 992 176 976 176
WIRE 1104 176 1104 -96
WIRE 1152 176 1104 176
WIRE 1216 176 1152 176
WIRE 1360 176 1296 176
WIRE 1488 176 1360 176
WIRE 1616 176 1488 176
WIRE 144 192 112 192
WIRE -176 208 -176 160
WIRE 432 208 432 176
WIRE 528 208 528 176
WIRE 656 208 608 208
WIRE 1104 208 1104 176
WIRE 1360 208 1360 176
WIRE 1488 208 1488 176
WIRE 112 224 112 192
WIRE 176 224 176 208
WIRE 608 240 608 208
WIRE 1616 240 1616 176
WIRE 1488 304 1488 272
WIRE -176 320 -176 288
WIRE 1104 320 1104 288
WIRE 1360 320 1360 272
WIRE 432 336 432 288
WIRE 528 336 528 272
WIRE -176 416 -176 400
WIRE 1488 416 1488 384
WIRE 1616 416 1616 320
WIRE 208 432 208 416
WIRE 352 432 352 416
WIRE 208 528 208 512
WIRE 352 528 352 512
FLAG 432 336 0
FLAG 608 240 0
FLAG 1104 320 0
FLAG 1360 320 0
FLAG 1488 416 0
FLAG 448 64 0
FLAG 704 32 0
FLAG 992 176 pwm1
FLAG 208 528 0
FLAG 352 528 0
FLAG 208 416 +V
FLAG 352 416 -V
FLAG 176 128 +V
FLAG 176 224 -V
FLAG 1616 416 0
FLAG 112 224 0
FLAG 1616 176 out
FLAG -176 160 in
FLAG -176 416 0
FLAG 288 176 1
FLAG 496 176 2
FLAG 1152 176 pwm
FLAG 128 -96 3
FLAG 672 -96 4
FLAG 528 336 0
SYMBOL Opamps\\LT1220 176 112 R0
SYMATTR InstName U1
SYMBOL res -96 176 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value 5.62k
SYMBOL res 288 192 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R2
SYMATTR Value 10k
SYMBOL res 416 192 R0
SYMATTR InstName R3
SYMATTR Value 6.8k
SYMBOL Digital\\diffschmitt 656 128 R0
SYMATTR InstName A1
SYMATTR SpiceLine Vt=0 Vh=1m
SYMBOL Digital\\inv 768 112 R0
WINDOW 39 -2 102 Left 2
SYMATTR SpiceLine Td=100n
SYMATTR InstName A2
SYMBOL bv 1104 192 R0
WINDOW 3 -81 172 Left 2
SYMATTR Value V=IF(V(pwm1)>0.5, 50, -50)
SYMATTR InstName B1
SYMBOL ind 1200 192 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 5 56 VBottom 2
WINDOW 39 -23 56 VBottom 2
SYMATTR InstName L1
SYMATTR Value 10µ
SYMATTR SpiceLine Rser=0.02
SYMBOL cap 1344 208 R0
SYMATTR InstName C1
SYMATTR Value 0.47µ
SYMBOL cap 1472 208 R0
SYMATTR InstName C2
SYMATTR Value 0.22µ
SYMBOL res 1472 288 R0
SYMATTR InstName R4
SYMATTR Value 40
SYMBOL res 512 -80 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R5
SYMATTR Value 46.4k
SYMBOL cap 240 -64 R0
SYMATTR InstName C3
SYMATTR Value 1n
SYMBOL cap 240 64 R0
SYMATTR InstName C4
SYMATTR Value 1n
SYMBOL res 320 48 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R6
SYMATTR Value 1k
SYMBOL res 752 -80 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R7
SYMATTR Value 1k
SYMBOL cap 688 -64 R0
SYMATTR InstName C5
SYMATTR Value 220p
SYMBOL voltage -176 192 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value PULSE(-1 1 200u 10u 10u 500u 1m)
SYMBOL voltage 208 416 R0
SYMATTR InstName V2
SYMATTR Value 5
SYMBOL voltage 352 416 R0
SYMATTR InstName V3
SYMATTR Value -5
SYMBOL res 1600 224 R0
SYMATTR InstName ^RL
SYMATTR Value 8
SYMBOL Digital\\inv 912 112 R0
WINDOW 39 -2 102 Left 2
SYMATTR SpiceLine Td=100n
SYMATTR InstName A3
SYMBOL voltage -176 304 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V4
SYMATTR Value SINE(0 0 1000 100u)
SYMBOL cap 512 208 R0
SYMATTR InstName C6
SYMATTR Value 10p
TEXT -192 520 Left 2 !.tran 0 2m 0 0.01u uic
TEXT -192 552 Left 2 !.options plotwinsize=0