* SPICE netlist
R1 N015 0 40K
R2 N013 0 40K
R3 N010 0 178K
R4 N007 N006 52.3K
R5 N008 0 10m
MQ1 N003 N005 N008 N008 Si7868DP
C1 N014 N012 .002
R6 N012 N011 4.7K
L1 IN N003 100
L2 N001 0 100
D1 N001 N002 MURS120
D2 0 N002 MURS120
L3 N002 OUT 4 Rpar=1K
C2 OUT 0 20 Rser=10m
R7 OUT N014 43.7K
R8 N014 0 4.99K
R9 N004 IN 178K
R10 0 N004 {178K/10}
V1 IN 0 20
C3 N006 0 .005
R11 N008 N009 1K
XU1 N011 N014 N010 MP_01 N006 N007 N004 0 N015 N009 N008 N013 0 N005 IN N016 LT1952-1 ;pnba Comp)FB)Rosc))SS_MAXDC)Vref)SD_Vsec)GND)Blank)Isense)OC)Delay)PGND)OUT)Vin)SOUT
Rload OUT 0 5
K1 L1 L2 1
.tran 1.2m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1536 672
WIRE -512 -336 -752 -336
WIRE -160 -336 -512 -336
WIRE 176 -336 -160 -336
WIRE 320 -336 224 -336
WIRE 432 -336 384 -336
WIRE 512 -336 432 -336
WIRE 624 -336 592 -336
WIRE 688 -336 624 -336
WIRE 768 -336 688 -336
WIRE -512 -320 -512 -336
WIRE 176 -320 176 -336
WIRE 224 -320 224 -336
WIRE 432 -320 432 -336
WIRE 624 -320 624 -336
WIRE 768 -320 768 -336
WIRE -752 -288 -752 -336
WIRE -512 -224 -512 -240
WIRE 176 -224 176 -240
WIRE 224 -224 224 -240
WIRE 432 -224 432 -256
WIRE 624 -224 624 -256
WIRE 768 -224 768 -240
WIRE -160 -192 -160 -336
WIRE -752 -144 -752 -208
WIRE -352 -144 -752 -144
WIRE 128 -144 16 -144
WIRE -752 -128 -752 -144
WIRE -544 -64 -560 -64
WIRE -464 -64 -480 -64
WIRE -448 -64 -464 -64
WIRE -352 -64 -368 -64
WIRE 128 -64 16 -64
WIRE 176 -64 176 -128
WIRE 176 -64 128 -64
WIRE 176 -48 176 -64
WIRE -752 -32 -752 -48
WIRE -464 16 -464 -64
WIRE -352 16 -464 16
WIRE 32 16 16 16
WIRE 128 16 128 -64
WIRE 128 16 112 16
WIRE 176 48 176 32
WIRE 688 64 688 -336
WIRE -448 96 -512 96
WIRE -352 96 -368 96
WIRE 32 96 16 96
WIRE 128 96 112 96
WIRE -496 176 -512 176
WIRE -352 176 -416 176
WIRE 128 176 128 160
WIRE 128 176 16 176
WIRE 688 176 688 144
WIRE 688 176 128 176
WIRE 688 192 688 176
WIRE -448 256 -512 256
WIRE -352 256 -368 256
WIRE 48 256 16 256
WIRE 688 288 688 272
WIRE -240 336 -240 320
WIRE -80 336 -80 320
FLAG -512 256 0
FLAG -512 176 0
FLAG -512 96 0
FLAG 176 48 0
FLAG -240 336 0
FLAG -80 336 0
FLAG 624 -224 0
FLAG 432 -224 0
FLAG 224 -224 0
FLAG 768 -224 0
FLAG 688 288 0
FLAG -752 -32 0
FLAG -512 -224 0
FLAG -560 -64 0
FLAG -512 -336 IN
FLAG 768 -336 OUT
SYMBOL res -352 240 R90
SYMATTR InstName R1
SYMATTR Value 40K
SYMBOL res -400 160 R90
SYMATTR InstName R2
SYMATTR Value 40K
SYMBOL res -352 80 R90
SYMATTR InstName R3
SYMATTR Value 178K
SYMBOL res -352 -48 M270
SYMATTR InstName R4
SYMATTR Value 52.3K
SYMBOL res 160 -64 R0
SYMATTR InstName R5
SYMATTR Value 10m
SYMBOL nmos 128 -224 R0
SYMATTR InstName Q1
SYMATTR Value Si7868DP
SYMBOL cap 112 160 M180
SYMATTR InstName C1
SYMATTR Value .002
SYMBOL res 128 80 R90
SYMATTR InstName R6
SYMATTR Value 4.7K
SYMBOL ind2 160 -336 R0
SYMATTR InstName L1
SYMATTR Value 100
SYMATTR Type ind
SYMBOL ind2 240 -336 M0
SYMATTR InstName L2
SYMATTR Value 100
SYMATTR Type ind
SYMBOL diode 320 -320 R270
SYMATTR InstName D1
SYMATTR Value MURS120
SYMBOL diode 416 -256 M180
SYMATTR InstName D2
SYMATTR Value MURS120
SYMBOL ind 496 -320 R270
SYMATTR InstName L3
SYMATTR Value 4
SYMATTR SpiceLine Rpar=1K
SYMBOL cap 608 -320 R0
SYMATTR InstName C2
SYMATTR Value 20
SYMATTR SpiceLine Rser=10m
SYMBOL res 672 48 R0
SYMATTR InstName R7
SYMATTR Value 43.7K
SYMBOL res 672 176 R0
SYMATTR InstName R8
SYMATTR Value 4.99K
SYMBOL res -768 -192 M180
SYMATTR InstName R9
SYMATTR Value 178K
SYMBOL res -768 -32 M180
SYMATTR InstName R10
SYMATTR Value {178K/10}
SYMBOL voltage -512 -336 R0
SYMATTR InstName V1
SYMATTR Value 20
SYMBOL cap -480 -80 R90
SYMATTR InstName C3
SYMATTR Value .005
SYMBOL res 128 32 M270
SYMATTR InstName R11
SYMATTR Value 1K
SYMBOL PowerProducts\\LT1952-1 -160 48 R0
SYMATTR InstName U1
SYMBOL res 752 -336 R0
SYMATTR InstName Rload
SYMATTR Value 5