Version 4 SHEET 1 1088 680 WIRE -192 -96 -208 -96 WIRE -64 -96 -64 -112 WIRE -64 -96 -112 -96 WIRE 256 -96 -64 -96 WIRE 384 -96 336 -96 WIRE 400 -96 384 -96 WIRE 480 -96 464 -96 WIRE 544 -96 480 -96 WIRE 688 -96 544 -96 WIRE 688 -64 688 -96 WIRE -208 -48 -208 -96 WIRE 544 -32 544 -96 WIRE -64 -16 -96 -16 WIRE -48 -16 -64 -16 WIRE 224 -16 224 -32 WIRE 256 -16 224 -16 WIRE 352 -16 336 -16 WIRE 416 -16 352 -16 WIRE -384 0 -384 -16 WIRE -384 0 -416 0 WIRE 352 0 352 -16 WIRE -416 16 -416 0 WIRE -96 32 -96 -16 WIRE -384 48 -384 0 WIRE -368 48 -384 48 WIRE -128 48 -144 48 WIRE -64 48 -64 -16 WIRE -48 48 -64 48 WIRE 192 48 176 48 WIRE 480 48 480 -96 WIRE -128 64 -128 48 WIRE 192 64 192 48 WIRE 688 64 688 16 WIRE 608 80 608 64 WIRE 352 96 352 80 WIRE 544 96 544 48 WIRE 576 96 544 96 WIRE -416 112 -416 96 WIRE -368 112 -416 112 WIRE -128 112 -144 112 WIRE -48 112 -64 112 WIRE 192 112 176 112 WIRE 656 112 640 112 WIRE -416 128 -416 112 WIRE -128 128 -128 112 WIRE -128 128 -384 128 WIRE 384 128 384 -96 WIRE 416 128 416 -16 WIRE 576 128 416 128 WIRE 192 144 192 112 WIRE 192 144 -128 144 WIRE 544 144 544 96 WIRE -384 176 -384 128 WIRE -368 176 -384 176 WIRE -144 176 -144 144 WIRE -128 176 -128 144 WIRE -128 176 -144 176 WIRE -96 176 -96 112 WIRE -64 176 -64 112 WIRE -64 176 -96 176 WIRE -48 176 -64 176 WIRE 240 176 176 176 WIRE -416 224 -416 208 WIRE -384 224 -384 176 WIRE -384 224 -416 224 WIRE -48 240 -64 240 WIRE 480 240 480 112 WIRE 544 240 544 224 WIRE 544 240 480 240 WIRE 608 240 608 144 WIRE 608 240 544 240 WIRE -96 256 -96 176 WIRE 384 256 384 224 WIRE 480 256 480 240 WIRE -64 288 -64 240 WIRE 656 288 656 112 WIRE 656 288 -64 288 WIRE -416 304 -416 288 WIRE -96 336 -96 320 FLAG -128 64 0 FLAG 192 64 0 FLAG -208 -48 0 FLAG -416 304 0 FLAG -96 336 0 FLAG 384 256 0 FLAG 480 256 0 FLAG 688 64 0 FLAG 352 96 0 FLAG -64 -112 +5 FLAG 608 64 +5 FLAG 224 -32 +5 FLAG -384 -16 +5 FLAG -144 240 +5 FLAG 176 240 +5 FLAG -48 -16 +5 SYMBOL Misc\\NE555 -256 144 M0 SYMATTR InstName U1 SYMBOL Misc\\NE555 64 144 M0 SYMATTR InstName U2 SYMBOL Misc\\battery -96 -96 R90 WINDOW 0 -32 56 VBottom 0 WINDOW 3 39 48 VTop 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 5 SYMBOL res -432 0 R0 WINDOW 0 -39 46 Left 0 WINDOW 3 -46 85 Left 0 SYMATTR InstName R1 SYMATTR Value 56k SYMBOL res -432 112 R0 WINDOW 0 -37 42 Left 0 WINDOW 3 -49 80 Left 0 SYMATTR InstName R2 SYMATTR Value 4.7k SYMBOL cap -432 224 R0 WINDOW 0 -34 17 Left 0 WINDOW 3 -51 60 Left 0 SYMATTR InstName C1 SYMATTR Value .001µ SYMBOL res -112 16 R0 WINDOW 0 -19 19 Left 0 WINDOW 3 25 50 Left 0 SYMATTR InstName R3 SYMATTR Value 10k SYMBOL cap -112 256 R0 WINDOW 0 -15 10 Left 0 WINDOW 3 -60 54 Left 0 SYMATTR InstName C2 SYMATTR Value .0022µ SYMBOL npn 320 128 R0 SYMATTR InstName Q1 SYMATTR Value 2N4401 SYMBOL res 336 160 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R4 SYMATTR Value 100 SYMBOL ind 240 -80 R270 WINDOW 0 36 55 VTop 0 WINDOW 3 -1 59 VBottom 0 SYMATTR InstName L1 SYMATTR Value 470µ SYMATTR SpiceLine Rser=7 SYMBOL diode 400 -80 R270 WINDOW 0 37 32 VTop 0 WINDOW 3 -7 36 VBottom 0 SYMATTR InstName D1 SYMATTR Value 1N914 SYMBOL cap 464 48 R0 WINDOW 0 -27 11 Left 0 WINDOW 3 22 10 Left 0 SYMATTR InstName C3 SYMATTR Value 22µ SYMBOL res 528 -48 R0 WINDOW 3 33 49 Left 0 WINDOW 0 -29 65 Left 0 SYMATTR Value 10k SYMATTR InstName R5 SYMBOL res 528 128 R0 WINDOW 0 -29 62 Left 0 WINDOW 3 27 84 Left 0 SYMATTR InstName R6 SYMATTR Value 2.2k SYMBOL res 672 -80 R0 SYMATTR InstName RL SYMATTR Value 560 SYMBOL res 336 -16 R0 WINDOW 0 -30 58 Left 0 WINDOW 3 -31 93 Left 0 SYMATTR InstName R8 SYMATTR Value 1k SYMBOL res 352 -32 R90 WINDOW 0 59 93 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R9 SYMATTR Value 1k SYMBOL Opamps\\LT1797 608 48 R0 SYMATTR InstName U3 TEXT -376 -104 Left 0 !.tran 15m TEXT -232 -264 Left 0 ;This circuit is from Schuler's Experiments Manual, 7th ed., pages 297-298.\nIt has poor efficiency (<40%) and high ripple. L1 has 7 ohms of \nresistance which is the biggest single detriment to circuit performance. \nOpen the file "DCtoDC2" to evaluate an improved version.