* SPICE netlist
L1 N002 N001 200 Rser=.2
L2 OUT N003 3.125 Rser=12m
L3 N022 0 50 Rser=.215
MQ1 N002 N009 N011 N011 Si4490DY
R1 N011 0 .04
C1 0 N019 1500p
R2 N014 N015 330
C2 N016 N015 .1
C3 N007 N017 2200p
R3 N007 0 10K
D1 0 N007 BAT54
Q2 0 N007 N010 0 2N2907
MQ3 N003 N010 0 0 Si4466DY
Q4 N006 N007 N010 0 2N2222
C4 N006 0 1
D2 N003 N005 BAT54
R4 N005 N006 47
C5 OUT 0 150 x3
C8 OUT 0 1
R7 N021 0 3.4K
R8 N022 N021 33.8K
L4 0 N016 1500 Rser=1.5
L5 0 N017 1500 Rser=1.5
V1 N001 0 48
R9 N023 0 1.225K
C9 N024 0 .1
C10 N012 0 47p
R10 N018 0 51K
R11 N020 0 100K
R12 N013 0 50K
V2 N004 0 16
Rload OUT 0 1
XU1 N014 N004 N020 N018 0 N008 N012 N021 N019 N004 0 N011 N024 N023 N013 N009 0 LT3825 ;pnba SG)Vcc)Ton)ENDLY)SYNC)SFST)OSC)FB)Vc)UVLO)Sense-)Sense+)Ccmp)Rcmp)PGDLY)PG)GND
K1 L1 L2 L3 1
K2 L4 L5 1
.tran 1m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1248 768
WIRE 0 -384 -160 -384
WIRE 336 -384 208 -384
WIRE 448 -384 336 -384
WIRE 528 -384 448 -384
WIRE -160 -368 -160 -384
WIRE 0 -368 0 -384
WIRE 96 -368 0 -368
WIRE 208 -368 208 -384
WIRE 208 -368 144 -368
WIRE 336 -368 336 -384
WIRE 448 -368 448 -384
WIRE 528 -368 528 -384
WIRE 96 -352 96 -368
WIRE 144 -352 144 -368
WIRE 336 -288 336 -304
WIRE 448 -288 448 -304
WIRE -160 -272 -160 -288
WIRE 96 -256 96 -272
WIRE 96 -256 0 -256
WIRE 144 -256 144 -272
WIRE 208 -256 144 -256
WIRE -352 -240 -576 -240
WIRE -224 -240 -352 -240
WIRE 0 -240 0 -256
WIRE 208 -240 208 -256
WIRE 240 -240 208 -240
WIRE 336 -240 304 -240
WIRE 448 -240 416 -240
WIRE 512 -240 448 -240
WIRE -576 -224 -576 -240
WIRE 448 -224 448 -240
WIRE 512 -224 512 -240
WIRE -352 -208 -352 -240
WIRE -224 -208 -224 -240
WIRE 208 -192 208 -240
WIRE 624 -176 576 -176
WIRE -464 -160 -480 -160
WIRE -48 -160 -112 -160
WIRE 448 -144 448 -160
WIRE -576 -128 -576 -144
WIRE 512 -112 512 -128
WIRE 512 -112 256 -112
WIRE 512 -96 512 -112
WIRE -464 -80 -480 -80
WIRE 0 -80 0 -144
WIRE 0 -80 -112 -80
WIRE 208 -80 208 -96
WIRE 624 -48 624 -176
WIRE 624 -48 576 -48
WIRE -608 0 -624 0
WIRE -464 0 -544 0
WIRE 0 0 -112 0
WIRE 0 16 0 0
WIRE 512 16 512 0
WIRE -560 80 -624 80
WIRE -464 80 -480 80
WIRE -64 80 -112 80
WIRE 32 80 16 80
WIRE 192 80 96 80
WIRE 336 80 240 80
WIRE 464 80 400 80
WIRE 624 80 624 -48
WIRE 624 80 464 80
WIRE 192 96 192 80
WIRE 240 96 240 80
WIRE 464 96 464 80
WIRE 624 96 624 80
WIRE -608 160 -624 160
WIRE -464 160 -528 160
WIRE -96 160 -112 160
WIRE -16 160 -32 160
WIRE 192 192 192 176
WIRE 240 192 240 176
WIRE 464 192 464 176
WIRE 624 192 624 160
WIRE -560 240 -624 240
WIRE -464 240 -480 240
WIRE 48 240 -112 240
WIRE 112 240 48 240
WIRE 240 240 192 240
WIRE 48 256 48 240
WIRE 240 256 240 240
WIRE -608 320 -624 320
WIRE -464 320 -528 320
WIRE -96 320 -112 320
WIRE -16 320 -32 320
WIRE 48 352 48 336
WIRE 240 352 240 336
WIRE -288 384 -288 368
FLAG 0 16 0
FLAG -16 160 0
FLAG 208 -80 0
FLAG 448 -144 0
FLAG 448 -288 0
FLAG 336 -288 0
FLAG 528 -288 0
FLAG 528 -384 OUT
FLAG 624 192 0
FLAG 464 192 0
FLAG 512 16 0
FLAG 240 192 0
FLAG 192 192 0
FLAG 240 352 0
FLAG 48 352 0
FLAG -288 384 0
FLAG -160 -272 0
FLAG -624 320 0
FLAG -16 320 0
FLAG -624 0 0
FLAG -480 -80 0
FLAG -624 160 0
FLAG -624 240 0
FLAG -624 80 0
FLAG -576 -128 0
SYMBOL ind2 80 -256 M180
SYMATTR InstName L1
SYMATTR Value 200
SYMATTR Type ind
SYMATTR SpiceLine Rser=.2
SYMBOL ind2 160 -368 M0
SYMATTR InstName L2
SYMATTR Value 3.125
SYMATTR Type ind
SYMATTR SpiceLine Rser=12m
SYMBOL ind2 224 240 R0
SYMATTR InstName L3
SYMATTR Value 50
SYMATTR Type ind
SYMATTR SpiceLine Rser=.215
SYMBOL nmos -48 -240 R0
SYMATTR InstName Q1
SYMATTR Value Si4490DY
SYMBOL res -16 -96 R0
SYMATTR InstName R1
SYMATTR Value .04
SYMBOL cap -32 144 R90
SYMATTR InstName C1
SYMATTR Value 1500p
SYMBOL res -80 96 R270
SYMATTR InstName R2
SYMATTR Value 330
SYMBOL cap 96 64 R90
SYMATTR InstName C2
SYMATTR Value .1
SYMBOL cap 400 64 R90
SYMATTR InstName C3
SYMATTR Value 2200p
SYMBOL res 448 80 R0
SYMATTR InstName R3
SYMATTR Value 10K
SYMBOL schottky 608 160 M180
SYMATTR InstName D1
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL pnp 576 0 R180
SYMATTR InstName Q2
SYMATTR Value 2N2907
SYMBOL nmos 256 -192 M0
SYMATTR Value Si4466DY
SYMATTR InstName Q3
SYMBOL npn 576 -224 M0
SYMATTR InstName Q4
SYMATTR Value 2N2222
SYMBOL cap 432 -224 R0
SYMATTR Value 1
SYMATTR InstName C4
SYMBOL schottky 240 -224 R270
SYMATTR InstName D2
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 320 -224 R270
SYMATTR InstName R4
SYMATTR Value 47
SYMBOL cap 320 -368 R0
SYMATTR Value 150
SYMATTR SpiceLine2 x3
SYMATTR InstName C5
SYMBOL cap 432 -368 R0
SYMATTR InstName C8
SYMATTR Value 1
SYMBOL res 32 240 R0
SYMATTR InstName R7
SYMATTR Value 3.4K
SYMBOL res 208 224 R90
SYMATTR InstName R8
SYMATTR Value 33.8K
SYMBOL ind2 176 192 M180
SYMATTR InstName L4
SYMATTR Value 1500
SYMATTR Type ind
SYMATTR SpiceLine Rser=1.5
SYMBOL ind2 256 192 R180
SYMATTR InstName L5
SYMATTR Value 1500
SYMATTR Type ind
SYMATTR SpiceLine Rser=1.5
SYMBOL voltage -160 -384 R0
SYMATTR InstName V1
SYMATTR Value 48
SYMBOL res -512 304 R90
SYMATTR InstName R9
SYMATTR Value 1.225K
SYMBOL cap -96 336 R270
SYMATTR InstName C9
SYMATTR Value .1
SYMBOL cap -544 -16 R90
SYMATTR InstName C10
SYMATTR Value 47p
SYMBOL res -512 144 R90
SYMATTR InstName R10
SYMATTR Value 51K
SYMBOL res -464 224 R90
SYMATTR InstName R11
SYMATTR Value 100K
SYMBOL res -464 64 R90
SYMATTR InstName R12
SYMATTR Value 50K
SYMBOL voltage -576 -240 R0
SYMATTR InstName V2
SYMATTR Value 16
SYMBOL res 512 -384 R0
SYMATTR InstName Rload
SYMATTR Value 1
SYMBOL LT3825 -288 80 R0
SYMATTR InstName U1