* SPICE netlist
C1 N004 0 4.7
MQ1 N001 N005 N007 N007 Si4850EY
R1 N007 0 10m
L1 IN N001 22 Rpar=2K
R2 N002 N008 2Meg
R3 N008 0 57K
D1 N001 N002 MBRS360
R4 N002 N009 .1
C2 N002 0 5
V1 IN 0 10
R5 IN N003 1Meg
R6 N003 0 200K
C3 N010 0 1000p Rser=10K
MQ2 N012 N014 0 0 Si4850EY
D2 N009 N012 LXK2-PW14 N=10
C4 N011 0 .01
R7 N013 0 28.7K
XU1 N006 N006 0 N011 N013 N003 N004 IN N007 N005 N014 N008 N009 N002 N010 N006 0 LT3755-1 ;pnba Vref)PWMin)SYNC)SS)Rt)_SHDN/UVLO)INTVcc)Vin)Sense)Gate)PWMout)FB)ISN)ISP)Vc)CTRL)GND
.tran 2m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1216 640
WIRE -480 -320 -608 -320
WIRE -96 -320 -480 -320
WIRE 48 -320 -96 -320
WIRE 240 -320 128 -320
WIRE 288 -320 240 -320
WIRE 384 -320 352 -320
WIRE 480 -320 384 -320
WIRE 608 -320 480 -320
WIRE -608 -304 -608 -320
WIRE -480 -304 -480 -320
WIRE 480 -304 480 -320
WIRE -96 -272 -96 -320
WIRE 240 -224 240 -320
WIRE 480 -224 480 -240
WIRE -608 -208 -608 -224
WIRE -480 -208 -480 -224
WIRE -272 -208 -480 -208
WIRE 96 -208 80 -208
WIRE 176 -208 160 -208
WIRE -480 -192 -480 -208
WIRE -272 -144 -288 -144
WIRE 192 -144 80 -144
WIRE 384 -144 384 -320
WIRE 608 -112 608 -320
WIRE 608 -112 512 -112
WIRE -480 -96 -480 -112
WIRE 608 -96 608 -112
WIRE -272 -80 -288 -80
WIRE 240 -80 240 -128
WIRE 240 -80 80 -80
WIRE 240 -64 240 -80
WIRE 384 -48 384 -64
WIRE 384 -48 336 -48
WIRE 384 -32 384 -48
WIRE -288 -16 -288 -80
WIRE -288 -16 -544 -16
WIRE -272 -16 -288 -16
WIRE 608 0 608 -16
WIRE 608 0 544 0
WIRE 608 32 608 0
WIRE -480 48 -496 48
WIRE -272 48 -416 48
WIRE 336 48 336 -48
WIRE 336 48 80 48
WIRE 384 64 384 48
WIRE -352 112 -368 112
WIRE -272 112 -288 112
WIRE 512 112 512 -112
WIRE 512 112 80 112
WIRE 608 160 608 96
WIRE -448 176 -480 176
WIRE -272 176 -368 176
WIRE 544 176 544 0
WIRE 544 176 80 176
WIRE -544 240 -544 -16
WIRE -272 240 -544 240
WIRE 560 240 80 240
WIRE 608 272 608 256
WIRE -96 320 -96 304
FLAG 176 -208 0
FLAG 240 16 0
FLAG 384 64 0
FLAG 480 -224 0
FLAG -608 -208 0
FLAG -480 -96 0
FLAG -496 48 0
FLAG 608 272 0
FLAG -368 112 0
FLAG -480 176 0
FLAG -96 320 0
FLAG -608 -320 IN
FLAG -288 -144 0
SYMBOL cap 96 -192 R270
SYMATTR InstName C1
SYMATTR Value 4.7
SYMBOL nmos 192 -224 R0
SYMATTR InstName Q1
SYMATTR Value Si4850EY
SYMBOL res 224 -80 R0
SYMATTR InstName R1
SYMATTR Value 10m
SYMBOL ind 32 -304 R270
SYMATTR InstName L1
SYMATTR Value 22
SYMATTR SpiceLine Rpar=2K
SYMBOL res 368 -160 R0
SYMATTR InstName R2
SYMATTR Value 2Meg
SYMBOL res 368 -48 R0
SYMATTR InstName R3
SYMATTR Value 57K
SYMBOL schottky 288 -304 R270
SYMATTR InstName D1
SYMATTR Value MBRS360
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 592 -112 R0
SYMATTR InstName R4
SYMATTR Value .1
SYMBOL cap 464 -304 R0
SYMATTR InstName C2
SYMATTR Value 5
SYMBOL voltage -608 -320 R0
SYMATTR InstName V1
SYMATTR Value 10
SYMBOL res -496 -320 R0
SYMATTR InstName R5
SYMATTR Value 1Meg
SYMBOL res -496 -208 R0
SYMATTR InstName R6
SYMATTR Value 200K
SYMBOL cap -416 32 R90
SYMATTR InstName C3
SYMATTR Value 1000p
SYMATTR SpiceLine Rser=10K
SYMBOL nmos 560 160 R0
SYMATTR InstName Q2
SYMATTR Value Si4850EY
SYMBOL LED 592 32 R0
SYMATTR Value LXK2-PW14
SYMATTR Value2 N=10
SYMATTR InstName D2
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap -288 96 R90
SYMATTR InstName C4
SYMATTR Value .01
SYMBOL res -352 160 R90
SYMATTR InstName R7
SYMATTR Value 28.7K
SYMBOL PowerProducts\\LT3755-1 -96 16 R0
SYMATTR InstName U1