* SPICE netlist
MQ1 N005 N013 0 0 Si4420DY
R1 IN N001 1.5Meg
D1 N010 N008 1N5818
C1 N010 0 4.7
D2 0 N005 1N5818
MQ2 IN N003 N005 N005 Si4420DY
L1 N005 OUT 3.8
C2 OUT 0 470 Rser=50m
R2 N012 N011 2K
C3 N011 0 .005
R3 IN N002 3.3K
V1 IN 0 6
C4 N007 0 .001
C5 N005 N008 .22
XU1 0 N007 OUT N002 N009 N006 N012 0 N001 N014 OUT 0 0 NC_01 IN N010 N013 0 N005 N005 N003 N008 0 0 0 LTC3720 ;pnba VID2)Run/SS)Von)Pgood)Vrng)FCB)Ith)SGND)Ion)FB)Vosense)VID3)VID4)EXTVcc)Vin)INTVcc)BG)PGND)Sense+)SW)TG)Boost)VID0)VID1)Sense-
Rload OUT 0 .25
.tran 2m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1216 896
WIRE -496 -448 -608 -448
WIRE -256 -448 -496 -448
WIRE -96 -448 -256 -448
WIRE 224 -448 -96 -448
WIRE -608 -432 -608 -448
WIRE -256 -432 -256 -448
WIRE -496 -400 -496 -448
WIRE 224 -352 224 -448
WIRE -608 -336 -608 -352
WIRE -256 -336 -256 -352
WIRE -96 -336 -96 -448
WIRE -496 -272 -496 -320
WIRE -368 -272 -496 -272
WIRE 176 -272 16 -272
WIRE -384 -208 -400 -208
WIRE 80 -208 16 -208
WIRE 224 -208 224 -256
WIRE 224 -208 80 -208
WIRE 288 -208 224 -208
WIRE 352 -208 288 -208
WIRE 464 -208 432 -208
WIRE 512 -208 464 -208
WIRE 608 -208 512 -208
WIRE 512 -192 512 -208
WIRE 608 -192 608 -208
WIRE 288 -176 288 -208
WIRE -368 -144 -384 -144
WIRE 80 -144 80 -208
WIRE 80 -144 16 -144
WIRE 512 -96 512 -128
WIRE 608 -96 608 -112
WIRE -448 -80 -480 -80
WIRE -368 -80 -384 -80
WIRE 80 -80 16 -80
WIRE 288 -80 288 -112
WIRE 224 -32 224 -208
WIRE -368 -16 -384 -16
WIRE 80 -16 16 -16
WIRE -464 48 -480 48
WIRE -368 48 -384 48
WIRE 176 48 16 48
WIRE 80 64 80 -16
WIRE -368 112 -384 112
WIRE 48 112 16 112
WIRE -368 176 -384 176
WIRE 48 176 48 112
WIRE 48 176 16 176
WIRE 464 176 464 -208
WIRE 464 176 48 176
WIRE -368 240 -384 240
WIRE 32 240 16 240
WIRE -368 304 -384 304
WIRE 224 304 224 64
WIRE 224 304 16 304
WIRE -368 368 -384 368
WIRE 224 368 224 304
WIRE 224 368 16 368
WIRE 224 400 224 368
WIRE -176 448 -176 432
FLAG -176 448 0
FLAG 224 400 0
FLAG 80 128 0
FLAG 288 -80 0
FLAG 608 -96 0
FLAG 512 -96 0
FLAG -544 48 0
FLAG -608 -336 0
FLAG -480 -80 0
FLAG 608 -208 OUT
FLAG -384 368 0
FLAG -384 304 0
FLAG -384 240 0
FLAG -384 176 0
FLAG -384 112 0
FLAG -608 -448 IN
SYMBOL NMOS 176 -32 R0
SYMATTR InstName Q1
SYMATTR Value Si4420DY
SYMBOL RES -272 -448 R0
SYMATTR InstName R1
SYMATTR Value 1.5Meg
SYMBOL schottky 64 -16 M180
SYMATTR InstName D1
SYMATTR Value 1N5818
SYMBOL cap 64 64 R0
SYMATTR Value 4.7
SYMATTR InstName C1
SYMBOL schottky 272 -112 M180
SYMATTR InstName D2
SYMATTR Value 1N5818
SYMBOL nmos 176 -352 R0
SYMATTR InstName Q2
SYMATTR Value Si4420DY
SYMBOL ind 336 -192 R270
SYMATTR InstName L1
SYMATTR Value 3.8
SYMBOL polcap 496 -192 R0
SYMATTR SpiceLine Rser=50m
SYMATTR InstName C2
SYMATTR Value 470
SYMBOL res -368 32 R90
SYMATTR InstName R2
SYMATTR Value 2K
SYMBOL cap -480 32 R90
SYMATTR InstName C3
SYMATTR Value .005
SYMBOL res -512 -416 R0
SYMATTR InstName R3
SYMATTR Value 3.3K
SYMBOL VOLTAGE -608 -448 R0
SYMATTR InstName V1
SYMATTR Value 6
SYMBOL cap -384 -96 R90
SYMATTR InstName C4
SYMATTR Value .001
SYMBOL cap 64 -144 R0
SYMATTR Value .22
SYMATTR InstName C5
SYMBOL PowerProducts\\LTC3720 -176 16 R0
SYMATTR InstName U1
SYMBOL res 592 -208 R0
SYMATTR InstName Rload
SYMATTR Value .25