* SPICE netlist
V1 N002 0 36
R1 N004 0 82.5k
R2 N002 N004 1Meg
C1 N005 0 2n
R3 N010 0 49.9k
C2 N012 0 2.2n Rser=20k Cpar=100p
R4 N013 0 16.2k
R5 N009 N013 143k
L1 N007 N008 15 Rser=7m Rpar=2k
R6 N008 N009 8m
C3 N009 0 100
R7 N009 0 2
M1 N007 N011 0 0 Si7370DP
M2 N002 N006 N007 N007 Si7370DP
D1 0 N007 MBRS1100
C4 N003 N007 100n
D2 N001 N003 MBRS140
D3 N009 N001 1N4148
C5 N001 0 1
V2 N014 0 PULSE(0 2.5 0 10n 10n {0.5/305k} {1/305k})
XU2 N002 N004 N005 0 N013 N012 N014 N010 N009 N008 0 N011 N001 N007 N006 N003 0 LT3845A ;pnba Vin)_SHDN)Css)Burst_EN)FB)Vc)SYNC)Fset)Sense-)Sense+)PGND)BG)Vcc)SW)TG)Boost)SGND
.tran 1.5m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1616 944
WIRE -200 -456 -232 -456
WIRE -88 -456 -136 -456
WIRE 664 -456 -88 -456
WIRE -632 -392 -808 -392
WIRE -216 -392 -632 -392
WIRE 312 -392 -216 -392
WIRE -808 -360 -808 -392
WIRE -632 -360 -632 -392
WIRE -88 -344 -88 -456
WIRE 8 -344 -88 -344
WIRE 136 -344 72 -344
WIRE -216 -296 -216 -392
WIRE -88 -296 -88 -344
WIRE -808 -248 -808 -280
WIRE -632 -248 -632 -280
WIRE -392 -248 -632 -248
WIRE 136 -248 136 -344
WIRE 136 -248 104 -248
WIRE 152 -248 136 -248
WIRE 312 -248 312 -392
WIRE 664 -232 664 -456
WIRE -632 -216 -632 -248
WIRE -472 -168 -504 -168
WIRE -392 -168 -408 -168
WIRE 264 -168 104 -168
WIRE -632 -104 -632 -136
WIRE -392 -88 -440 -88
WIRE 216 -88 216 -248
WIRE 216 -88 104 -88
WIRE 312 -88 312 -152
WIRE 312 -88 216 -88
WIRE 376 -88 312 -88
WIRE 488 -88 456 -88
WIRE 520 -88 488 -88
WIRE 616 -88 600 -88
WIRE 664 -88 664 -168
WIRE 664 -88 616 -88
WIRE 808 -88 664 -88
WIRE 216 -72 216 -88
WIRE 312 -56 312 -88
WIRE 808 -56 808 -88
WIRE 664 -40 664 -88
WIRE -504 -8 -552 -8
WIRE -392 -8 -424 -8
WIRE 168 -8 104 -8
WIRE 216 8 216 -8
WIRE 168 24 168 -8
WIRE 264 24 168 24
WIRE 664 40 664 24
WIRE 808 40 808 24
WIRE 312 56 312 40
WIRE -712 72 -760 72
WIRE -392 72 -648 72
WIRE 488 72 488 -88
WIRE 488 72 104 72
WIRE -424 152 -488 152
WIRE -392 152 -424 152
WIRE 280 152 104 152
WIRE 616 152 616 -88
WIRE 616 152 280 152
WIRE -488 232 -488 152
WIRE -152 232 -152 200
WIRE -24 232 -24 200
WIRE -424 312 -424 152
WIRE 136 312 -424 312
WIRE 280 312 280 152
WIRE 280 312 216 312
WIRE -280 360 -280 200
WIRE -488 392 -488 312
WIRE -280 472 -280 440
FLAG -632 -104 0
FLAG -808 -248 0
FLAG -440 -88 0
FLAG -504 -168 0
FLAG -552 -8 0
FLAG -760 72 0
FLAG -488 392 0
FLAG 664 40 0
FLAG 808 40 0
FLAG 312 56 0
FLAG 216 8 0
FLAG -152 232 0
FLAG -24 232 0
FLAG -232 -456 0
FLAG -280 472 0
SYMBOL voltage -808 -376 R0
SYMATTR InstName V1
SYMATTR Value 36
SYMBOL res -648 -232 R0
SYMATTR InstName R1
SYMATTR Value 82.5k
SYMBOL res -648 -376 R0
SYMATTR InstName R2
SYMATTR Value 1Meg
SYMBOL cap -408 -184 R90
SYMATTR InstName C1
SYMATTR Value 2n
SYMBOL res -408 -24 R90
SYMATTR InstName R3
SYMATTR Value 49.9k
SYMBOL cap -648 56 R90
SYMATTR InstName C2
SYMATTR Value 2.2n
SYMATTR SpiceLine Rser=20k Cpar=100p
SYMBOL res -504 216 R0
SYMATTR InstName R4
SYMATTR Value 16.2k
SYMBOL res 232 296 R90
SYMATTR InstName R5
SYMATTR Value 143k
SYMBOL ind 360 -72 R270
SYMATTR InstName L1
SYMATTR Value 15
SYMATTR SpiceLine Rser=7m Rpar=2k
SYMBOL res 504 -72 R270
SYMATTR InstName R6
SYMATTR Value 8m
SYMBOL cap 648 -40 R0
SYMATTR InstName C3
SYMATTR Value 100
SYMBOL res 792 -72 R0
SYMATTR InstName R7
SYMATTR Value 2
SYMBOL nmos 264 -56 R0
SYMATTR InstName M1
SYMATTR Value Si7370DP
SYMBOL nmos 264 -248 R0
SYMATTR InstName M2
SYMATTR Value Si7370DP
SYMBOL schottky 232 -8 R180
SYMATTR InstName D1
SYMATTR Value MBRS1100
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 152 -232 R270
SYMATTR InstName C4
SYMATTR Value 100n
SYMBOL schottky 8 -328 R270
SYMATTR InstName D2
SYMATTR Value MBRS140
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL diode 680 -168 R180
SYMATTR InstName D3
SYMATTR Value 1N4148
SYMBOL cap -136 -472 R90
SYMATTR InstName C5
SYMATTR Value 1
SYMBOL voltage -280 344 R0
SYMATTR InstName V2
SYMATTR Value PULSE(0 2.5 0 10n 10n {0.5/305k} {1/305k})
SYMBOL LT3845A -152 -56 R0
SYMATTR InstName U2