* SPICE netlist
XU1 N003 N002 N004 N002 N009 N010 N008 0 N001 OUT N002 N011 0 N007 N006 N005 LTC3812-5 ;pnba Ion)Vrng)Pgood)FCB)Ith)FB)Run/SS)SGND)NDRV)EXTVcc)INTVcc)BG)PGND)SW)TG)Boost
R1 IN N003 110K
MQ1 IN N001 N002 N002 BSH114
R2 IN N001 100K
D1 N002 N005 1N4148
C1 N005 N007 .1
MQ2 IN N006 N007 N007 Si7850DP
MQ3 N007 N011 0 0 Si7850DP
C2 N002 0 1
L1 N007 OUT 4.7
D2 0 N007 MBRS1100
R3 OUT N010 10K
R4 N010 0 1.89K
C3 OUT 0 270 Rser=10m
C4 N009 N010 47p Rser=200K Cpar=5p
C5 N008 0 1000p
R5 OUT N004 100K
V1 IN 0 42
Rload OUT 0 2
.tran 2m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1312 832
WIRE 400 -416 -496 -416
WIRE -496 -384 -496 -416
WIRE -208 -384 -368 -384
WIRE 48 -384 -208 -384
WIRE 160 -384 48 -384
WIRE 240 -384 160 -384
WIRE -368 -368 -368 -384
WIRE -208 -368 -208 -384
WIRE 240 -368 240 -384
WIRE 48 -352 48 -384
WIRE -208 -272 -208 -288
WIRE 0 -272 -208 -272
WIRE 240 -272 240 -288
WIRE 48 -256 -512 -256
WIRE -368 -240 -368 -288
WIRE -208 -240 -208 -272
WIRE -496 -176 -496 -304
WIRE -480 -176 -496 -176
WIRE -64 -176 -96 -176
WIRE -48 -176 -64 -176
WIRE 48 -176 48 -256
WIRE 48 -176 16 -176
WIRE 160 -160 160 -384
WIRE -512 -80 -512 -256
WIRE -480 -80 -512 -80
WIRE 112 -80 -96 -80
WIRE -64 -64 -64 -176
WIRE -512 16 -512 -80
WIRE -480 16 -512 16
WIRE -64 16 -64 0
WIRE -64 16 -96 16
WIRE 160 16 160 -64
WIRE 160 16 -64 16
WIRE 208 16 160 16
WIRE 256 16 208 16
WIRE 400 16 400 -416
WIRE 400 16 336 16
WIRE 480 16 400 16
WIRE 656 16 480 16
WIRE 480 32 480 16
WIRE 656 32 656 16
WIRE 208 48 208 16
WIRE 48 64 48 -176
WIRE 48 64 -16 64
WIRE 48 80 48 64
WIRE -560 112 -576 112
WIRE -480 112 -496 112
WIRE -16 112 -16 64
WIRE -16 112 -96 112
WIRE 208 128 208 112
WIRE 400 128 400 16
WIRE 400 128 336 128
WIRE 480 128 480 96
WIRE 656 128 656 112
WIRE 400 144 400 128
WIRE 48 160 48 144
WIRE -480 208 -640 208
WIRE 336 208 336 128
WIRE 336 208 -96 208
WIRE -640 224 -640 208
WIRE 160 224 160 16
WIRE 400 256 400 224
WIRE 400 256 320 256
WIRE 400 272 400 256
WIRE -640 304 -640 288
WIRE -480 304 -640 304
WIRE 112 304 -96 304
WIRE 160 336 160 320
WIRE 400 368 400 352
WIRE -368 384 -368 368
WIRE -208 384 -208 368
WIRE -640 416 -640 304
WIRE 320 416 320 256
WIRE 320 416 -640 416
FLAG 160 336 0
FLAG 48 160 0
FLAG 208 128 0
FLAG -208 384 0
FLAG -368 384 0
FLAG 400 368 0
FLAG 480 128 0
FLAG 656 128 0
FLAG -576 112 0
FLAG 240 -272 0
FLAG 656 16 OUT
FLAG 240 -384 IN
SYMBOL PowerProducts\\LTC3812-5 -288 64 R0
SYMATTR InstName U1
SYMBOL res -384 -384 R0
SYMATTR InstName R1
SYMATTR Value 110K
SYMBOL nmos 0 -352 R0
SYMATTR InstName Q1
SYMATTR Value BSH114
SYMBOL res -224 -384 R0
SYMATTR InstName R2
SYMATTR Value 100K
SYMBOL diode 16 -192 R90
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL cap -80 -64 R0
SYMATTR InstName C1
SYMATTR Value .1
SYMBOL nmos 112 -160 R0
SYMATTR InstName Q2
SYMATTR Value Si7850DP
SYMBOL nmos 112 224 R0
SYMATTR InstName Q3
SYMATTR Value Si7850DP
SYMBOL cap 32 80 R0
SYMATTR InstName C2
SYMATTR Value 1
SYMBOL ind 240 32 R270
SYMATTR InstName L1
SYMATTR Value 4.7
SYMBOL schottky 192 112 M180
SYMATTR InstName D2
SYMATTR Value MBRS1100
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 384 128 R0
SYMATTR InstName R3
SYMATTR Value 10K
SYMBOL res 384 256 R0
SYMATTR InstName R4
SYMATTR Value 1.89K
SYMBOL cap 464 32 R0
SYMATTR SpiceLine Rser=10m
SYMATTR Value 270
SYMATTR InstName C3
SYMBOL cap -656 224 R0
SYMATTR SpiceLine Rser=200K
SYMATTR SpiceLine2 Cpar=5p
SYMATTR InstName C4
SYMATTR Value 47p
SYMBOL cap -496 96 R90
SYMATTR InstName C5
SYMATTR Value 1000p
SYMBOL res -512 -400 R0
SYMATTR InstName R5
SYMATTR Value 100K
SYMBOL voltage 240 -384 R0
SYMATTR InstName V1
SYMATTR Value 42
SYMBOL res 640 16 R0
SYMATTR InstName Rload
SYMATTR Value 2