* SPICE netlist
V1 IN 0 5
L1 IN N002 2.2 Rser=1.5m
D1 N002 N003 1N5818
C1 N003 0 10 Rser=5m
R1 N003 N004 130K
R2 N003 N001 6.3K
MQ1 OUT N001 N003 N003 Si4427DY
R3 N008 0 86.6K
C2 N009 0 .02
R4 IN N006 100K
R5 N005 0 10K
R6 IN N005 18.7K
C3 N007 0 2200p Rser=8K Cpar=47p
C4 OUT 0 10 Rser=5m
D2 IN N001 MBR0520L
XU1 N004 N007 N001 N006 IN N002 MP_01 MP_02 N002 MP_03 MP_04 MP_05 N005 N008 N009 MP_06 0 LT3579 ;pnba FB)Vc)Gate)_Fault)Vin)SW1)))SW2))))_SHDN)Rt)SS))GND
Rload OUT 0 7
.tran 2m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1216 592
WIRE 96 -296 -384 -296
WIRE 320 -296 160 -296
WIRE -512 -232 -608 -232
WIRE -384 -232 -384 -296
WIRE -384 -232 -512 -232
WIRE -320 -232 -384 -232
WIRE -192 -232 -240 -232
WIRE -96 -232 -192 -232
WIRE -64 -232 -96 -232
WIRE 48 -232 0 -232
WIRE 128 -232 48 -232
WIRE 224 -232 128 -232
WIRE 352 -232 224 -232
WIRE 512 -232 448 -232
WIRE 608 -232 512 -232
WIRE -608 -216 -608 -232
WIRE 48 -216 48 -232
WIRE 128 -216 128 -232
WIRE 224 -216 224 -232
WIRE 512 -216 512 -232
WIRE 608 -216 608 -232
WIRE -192 -168 -192 -232
WIRE -96 -168 -96 -232
WIRE 48 -136 48 -152
WIRE -608 -120 -608 -136
WIRE 512 -120 512 -152
WIRE 608 -120 608 -136
WIRE -512 -104 -512 -232
WIRE -384 -104 -384 -232
WIRE -288 -104 -384 -104
WIRE 128 -104 128 -136
WIRE 128 -104 0 -104
WIRE 224 -88 224 -136
WIRE 320 -88 320 -296
WIRE 320 -88 224 -88
WIRE -512 -8 -512 -24
WIRE -288 -8 -512 -8
WIRE 320 -8 320 -88
WIRE 320 -8 0 -8
WIRE 368 -8 368 -184
WIRE 368 -8 320 -8
WIRE -512 8 -512 -8
WIRE -384 8 -384 -104
WIRE -288 88 -384 88
WIRE 96 88 0 88
WIRE 192 88 160 88
WIRE -512 104 -512 88
WIRE -288 184 -384 184
WIRE 48 184 0 184
WIRE -384 200 -384 184
WIRE 48 200 48 184
WIRE -144 264 -144 248
WIRE -384 296 -384 280
WIRE 48 296 48 264
FLAG 48 -136 0
FLAG -608 -120 0
FLAG -608 -232 IN
FLAG -144 264 0
FLAG -384 296 0
FLAG 48 296 0
FLAG -512 104 0
FLAG 192 88 0
FLAG 512 -120 0
FLAG 608 -120 0
FLAG 608 -232 OUT
SYMBOL voltage -608 -232 R0
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL ind -336 -216 R270
SYMATTR InstName L1
SYMATTR Value 2.2
SYMATTR SpiceLine Rser=1.5m
SYMBOL schottky -64 -216 R270
SYMATTR InstName D1
SYMATTR Value 1N5818
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 32 -216 R0
SYMATTR InstName C1
SYMATTR Value 10
SYMATTR SpiceLine Rser=5m
SYMBOL res 112 -232 R0
SYMATTR InstName R1
SYMATTR Value 130K
SYMBOL res 208 -232 R0
SYMATTR Value 6.3K
SYMATTR InstName R2
SYMBOL pmos 448 -184 M270
SYMATTR InstName Q1
SYMATTR Value Si4427DY
SYMBOL res -400 184 R0
SYMATTR InstName R3
SYMATTR Value 86.6K
SYMBOL cap 32 200 R0
SYMATTR InstName C2
SYMATTR Value .02
SYMBOL res -400 -8 R0
SYMATTR InstName R4
SYMATTR Value 100K
SYMBOL res -528 -8 R0
SYMATTR InstName R5
SYMATTR Value 10K
SYMBOL res -528 -120 R0
SYMATTR InstName R6
SYMATTR Value 18.7K
SYMBOL cap 96 104 R270
SYMATTR InstName C3
SYMATTR Value 2200p
SYMATTR SpiceLine Rser=8K Cpar=47p
SYMBOL cap 496 -216 R0
SYMATTR InstName C4
SYMATTR Value 10
SYMATTR SpiceLine Rser=5m
SYMBOL schottky 96 -280 R270
SYMATTR InstName D2
SYMATTR Value MBR0520L
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL PowerProducts\\LT3579 -144 40 R0
SYMATTR InstName U1
SYMBOL res 592 -232 R0
SYMATTR InstName Rload
SYMATTR Value 7