Version 4
SHEET 1 1212 680
WIRE 192 16 144 16
WIRE 240 16 192 16
WIRE 352 16 320 16
WIRE 464 16 352 16
WIRE 592 16 512 16
WIRE 704 16 656 16
WIRE 816 16 704 16
WIRE 912 16 816 16
WIRE 192 32 192 16
WIRE 352 32 352 16
WIRE 464 32 464 16
WIRE 512 32 512 16
WIRE 704 32 704 16
WIRE 816 32 816 16
WIRE 912 32 912 16
WIRE 192 112 192 96
WIRE 352 128 352 112
WIRE 464 128 464 112
WIRE 512 128 512 112
WIRE 704 128 704 112
WIRE 704 128 624 128
WIRE 816 128 816 96
WIRE 912 128 912 112
WIRE 704 144 704 128
WIRE 144 160 144 16
WIRE 416 208 272 208
WIRE 464 240 464 224
WIRE 464 240 336 240
WIRE 704 240 704 224
WIRE 464 256 464 240
WIRE -64 272 -80 272
WIRE 16 272 0 272
WIRE 336 272 336 240
WIRE 336 272 272 272
WIRE 336 336 272 336
WIRE 464 352 464 336
WIRE 336 384 336 336
WIRE 624 384 624 128
WIRE 624 384 336 384
WIRE 144 400 144 384
FLAG 464 352 0
FLAG 352 128 0
FLAG 192 112 0
FLAG 144 400 0
FLAG 512 128 0
FLAG 704 240 0
FLAG 816 128 0
FLAG 912 128 0
FLAG -80 272 0
FLAG 352 16 IN
FLAG 912 16 OUT
SYMBOL voltage 352 16 R0
SYMATTR InstName V1
SYMATTR Value 30
SYMBOL ind2 448 16 R0
WINDOW 0 -1 36 Right 2
WINDOW 3 -5 69 Right 2
SYMATTR InstName L1
SYMATTR Value 50µ
SYMATTR Type ind
SYMBOL ind2 528 128 R180
WINDOW 0 -6 76 Right 2
WINDOW 3 -6 40 Right 2
SYMATTR InstName L2
SYMATTR Value 2µ
SYMATTR Type ind
SYMBOL nmos 416 128 R0
SYMATTR InstName Q1
SYMATTR Value BSS123
SYMBOL res 448 240 R0
SYMATTR InstName R1
SYMATTR Value 68m
SYMBOL res 336 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 10K
SYMBOL cap 176 32 R0
SYMATTR InstName C1
SYMATTR Value 10µ
SYMBOL res 688 16 R0
SYMATTR InstName R3
SYMATTR Value 105K
SYMBOL res 688 128 R0
SYMATTR InstName R4
SYMATTR Value 20K
SYMBOL schottky 592 32 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D1
SYMATTR Value 1N5817
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 800 32 R0
SYMATTR InstName C2
SYMATTR Value 300µ
SYMATTR SpiceLine Rser=50m
SYMBOL res 896 16 R0
SYMATTR InstName Rload
SYMATTR Value 2.5
SYMBOL cap 0 256 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C3
SYMATTR Value .001µ
SYMBOL LTC3803-3 144 272 R0
SYMATTR InstName U1
TEXT 488 16 Bottom 2 !K1 L1 L2 1.
TEXT 496 416 Left 2 !.tran 38m startup