* SPICE netlist
MQ1 N001 N003 OUT OUT Si4864DY
R1 IN N001 0.5m
R2 IN N007 34K
R3 N008 N007 1.74K
R4 N008 0 2.67K
R5 OUT N005 25.1K
R6 0 N005 3.57K
R7 OUT N009 24K
C1 N012 0 .068
C2 N013 0 .068
C3 N014 0 4
V1 N010 0 PWL(0 3.1)
V2 IN 0 PWL(0 0 100u 10 6 10 6.0000001 14)
C4 OUT 0 2000
R8 0 OUT 1000
MQ2 OUT N004 N002 N002 Si4864DY
V3 N004 0 PWL(0 0 6.2 0 6.2001 12)
R9 N003 N006 10
R10 0 N002 .05
V4 N011 0 PWL(0 3.1 1 3.1 1.0001 0)
XU1 N007 N008 N012 0 N010 N011 N014 N013 N009 N005 OUT N006 N001 IN IN LTC4280 uvautoretry=1 ovautoretry=1 ocautoretry=0 ;pnba UV)OV)FILTER)GND)ON)_EN)Timer)Vcc)GPIO)FB)Source)Gate)Sense-)Sense+)Vdd
.tran 16

* LTspice schematic (.asc)
Version 4
SHEET 1 2160 528
WIRE -552 -264 -1080 -264
WIRE -232 -264 -552 -264
WIRE -120 -264 -232 -264
WIRE -104 -264 -120 -264
WIRE -8 -264 -24 -264
WIRE 24 -264 -8 -264
WIRE 216 -264 120 -264
WIRE 488 -264 216 -264
WIRE 600 -264 488 -264
WIRE 696 -264 600 -264
WIRE 808 -264 696 -264
WIRE 888 -264 808 -264
WIRE 1080 -264 984 -264
WIRE -1080 -248 -1080 -264
WIRE -552 -248 -552 -264
WIRE 488 -248 488 -264
WIRE 696 -248 696 -264
WIRE 808 -248 808 -264
WIRE 1080 -248 1080 -264
WIRE 104 -200 104 -216
WIRE 968 -184 968 -216
WIRE -1080 -152 -1080 -168
WIRE 488 -152 488 -168
WIRE 488 -152 408 -152
WIRE 600 -152 600 -264
WIRE 696 -152 696 -184
WIRE 808 -152 808 -168
WIRE 1080 -152 1080 -168
WIRE 488 -120 488 -152
WIRE -232 -104 -232 -264
WIRE -120 -104 -120 -264
WIRE -8 -104 -8 -264
WIRE 104 -104 104 -120
WIRE 216 -104 216 -264
WIRE -552 -88 -552 -168
WIRE -440 -88 -552 -88
WIRE 968 -88 968 -104
WIRE -552 -72 -552 -88
WIRE -440 -40 -440 -88
WIRE -328 -40 -440 -40
WIRE 408 -40 408 -152
WIRE 408 -40 328 -40
WIRE 488 -24 488 -40
WIRE -552 24 -552 8
WIRE -328 24 -552 24
WIRE 600 24 600 -72
WIRE 600 24 328 24
WIRE -552 40 -552 24
WIRE -328 88 -440 88
WIRE 408 88 328 88
WIRE -440 104 -440 88
WIRE 408 120 408 88
WIRE -552 136 -552 120
WIRE -248 184 -248 168
WIRE 72 184 72 168
WIRE 232 184 232 168
WIRE -440 200 -440 184
WIRE -88 200 -88 168
WIRE 408 216 408 200
WIRE -248 264 -248 248
WIRE 72 264 72 248
WIRE 232 264 232 248
FLAG -552 136 0
FLAG -88 200 0
FLAG 488 -24 0
FLAG -248 264 0
FLAG 72 264 0
FLAG 232 264 0
FLAG -440 200 0
FLAG -1080 -152 0
FLAG 696 -152 0
FLAG 808 -152 0
FLAG 1080 -152 0
FLAG 968 -88 0
FLAG 408 216 0
FLAG -1080 -264 IN
FLAG 808 -264 OUT
SYMBOL nmos 24 -216 R270
SYMATTR InstName Q1
SYMATTR Value Si4864DY
SYMBOL res -120 -248 R270
SYMATTR InstName R1
SYMATTR Value 0.5m
SYMBOL res -568 -264 R0
SYMATTR InstName R2
SYMATTR Value 34K
SYMBOL res -568 24 M180
SYMATTR InstName R3
SYMATTR Value 1.74K
SYMBOL res -568 24 R0
SYMATTR InstName R4
SYMATTR Value 2.67K
SYMBOL res 472 -264 R0
SYMATTR InstName R5
SYMATTR Value 25.1K
SYMBOL res 472 -24 M180
SYMATTR InstName R6
SYMATTR Value 3.57K
SYMBOL res 584 -168 R0
SYMATTR InstName R7
SYMATTR Value 24K
SYMBOL cap -264 184 R0
SYMATTR InstName C1
SYMATTR Value .068
SYMBOL cap 56 184 R0
SYMATTR InstName C2
SYMATTR Value .068
SYMBOL cap 216 184 R0
SYMATTR InstName C3
SYMATTR Value 4
SYMBOL voltage -440 88 R0
SYMATTR InstName V1
SYMATTR Value PWL(0 3.1)
SYMBOL voltage -1080 -264 R0
SYMATTR InstName V2
SYMATTR Value PWL(0 0 100u 10 6 10 6.0000001 14)
SYMBOL cap 680 -248 R0
SYMATTR InstName C4
SYMATTR Value 2000
SYMBOL res 792 -152 M180
SYMATTR InstName R8
SYMATTR Value 1000
SYMBOL nmos 888 -216 R270
SYMATTR InstName Q2
SYMATTR Value Si4864DY
SYMBOL voltage 968 -200 R0
SYMATTR InstName V3
SYMATTR Value PWL(0 0 6.2 0 6.2001 12)
SYMBOL res 88 -216 R0
SYMATTR InstName R9
SYMATTR Value 10
SYMBOL res 1064 -152 M180
SYMATTR InstName R10
SYMATTR Value .05
SYMBOL voltage 408 104 R0
SYMATTR InstName V4
SYMATTR Value PWL(0 3.1 1 3.1 1.0001 0)
SYMBOL LTC4280 -8 24 R0
SYMATTR InstName U1