Version 4
SHEET 1 880 680
WIRE 96 80 -48 80
WIRE 192 80 96 80
WIRE 352 80 272 80
WIRE 416 80 352 80
WIRE 560 80 496 80
WIRE 704 80 560 80
WIRE -48 128 -48 80
WIRE 96 128 96 80
WIRE 352 128 352 80
WIRE 560 128 560 80
WIRE 704 128 704 80
WIRE 256 144 256 128
WIRE 208 240 208 128
WIRE 256 240 256 224
WIRE 256 240 208 240
WIRE -48 256 -48 208
WIRE 96 256 96 192
WIRE 256 256 256 240
WIRE 352 256 352 192
WIRE 560 256 560 192
WIRE 704 256 704 208
FLAG -48 256 0
FLAG 96 256 0
FLAG 560 256 0
FLAG 704 256 0
FLAG 352 256 0
FLAG 256 256 0
FLAG 704 80 OUT
SYMBOL voltage -48 112 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL cap 80 128 R0
SYMATTR InstName C1
SYMATTR Value 10µ
SYMBOL sw 176 80 R270
WINDOW 0 18 -8 VRight 2
WINDOW 3 50 24 VRight 2
SYMATTR InstName S1
SYMATTR Value FETsw
SYMBOL ind 400 96 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName L1
SYMATTR Value 220µ
SYMBOL schottky 336 192 M180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value 1N5819
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 544 128 R0
SYMATTR InstName C2
SYMATTR Value 10µ
SYMBOL res 688 112 R0
SYMATTR InstName R1
SYMATTR Value 5
SYMBOL voltage 256 128 R0
WINDOW 3 -51 162 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR Value PWL repeat forever (0s 0V 5us 1V 10us 0V) endrepeat
SYMATTR InstName V2
TEXT 24 0 Left 2 !.model FETsw sw(Vt={1-{Duty}} Ron=1u)
TEXT 496 0 Left 2 !.param Duty=5V/12V
TEXT -64 288 Left 2 !.tran 0 5m 0 .1u startup