* SPICE netlist
MQ1 N002 N005 N003 N003 Si4864DY
R1 N001 N002 5m
R2 N001 N007 34K
R3 N010 N007 1.74K
R4 N010 0 2.67K
R5 N003 N008 25.1K
R6 0 N008 3.57K
R7 N003 N011 24K
C1 N014 0 .068
C2 N015 0 .068
C3 N016 0 4
V1 N012 0 3.1
V2 N001 0 PWL(0 0 10u 0 100u 12 6 12)
C4 N003 0 2000
R8 0 N003 10
MQ2 N003 N006 N004 N004 Si4864DY
V3 N006 0 PWL(0 0 4 0 +100u 12 +200m 12 +100n 0)
R9 N005 N009 10
R10 0 N004 .05
V4 N013 0 PWL(0 3.1 1 3.1 +100u 0)
XU1 N007 N010 N014 0 N012 N013 N016 N015 N011 N008 N003 N009 N002 N001 N001 LTC4215-2 uvautoretry=1 ovautoretry=1 ocautoretry=1 ;pnba UV)OV)SS)GND)ON)_EN)Timer)Vcc)GPIO1)FB)Source)Gate)Sense-)Sense+)Vdd
.tran 12

* LTspice schematic (.asc)
Version 4
SHEET 1 2016 544
WIRE -592 -272 -1008 -272
WIRE -304 -272 -592 -272
WIRE -192 -272 -304 -272
WIRE -176 -272 -192 -272
WIRE -80 -272 -96 -272
WIRE -48 -272 -80 -272
WIRE 144 -272 48 -272
WIRE 384 -272 144 -272
WIRE 528 -272 384 -272
WIRE 624 -272 528 -272
WIRE 736 -272 624 -272
WIRE 816 -272 736 -272
WIRE 1008 -272 912 -272
WIRE -1008 -256 -1008 -272
WIRE 624 -256 624 -272
WIRE 736 -256 736 -272
WIRE 1008 -256 1008 -272
WIRE -592 -240 -592 -272
WIRE 384 -240 384 -272
WIRE 32 -192 32 -224
WIRE 896 -176 896 -224
WIRE -1008 -160 -1008 -176
WIRE 624 -160 624 -192
WIRE 736 -160 736 -176
WIRE 1008 -160 1008 -176
WIRE -592 -144 -592 -160
WIRE -480 -144 -592 -144
WIRE 384 -144 384 -160
WIRE 384 -144 304 -144
WIRE 528 -144 528 -272
WIRE 384 -112 384 -144
WIRE -592 -96 -592 -144
WIRE -304 -96 -304 -272
WIRE -192 -96 -192 -272
WIRE -80 -96 -80 -272
WIRE 32 -96 32 -112
WIRE 144 -96 144 -272
WIRE 896 -80 896 -96
WIRE -480 -32 -480 -144
WIRE -400 -32 -480 -32
WIRE 304 -32 304 -144
WIRE 304 -32 256 -32
WIRE 384 -16 384 -32
WIRE -592 32 -592 -16
WIRE -400 32 -592 32
WIRE 528 32 528 -64
WIRE 528 32 256 32
WIRE -592 48 -592 32
WIRE -400 96 -480 96
WIRE 320 96 256 96
WIRE -480 112 -480 96
WIRE 320 112 320 96
WIRE -592 144 -592 128
WIRE -320 192 -320 176
WIRE 0 192 0 176
WIRE 160 192 160 176
WIRE -480 208 -480 192
WIRE -160 208 -160 176
WIRE 320 208 320 192
WIRE -320 272 -320 256
WIRE 0 272 0 256
WIRE 160 272 160 256
FLAG -592 144 0
FLAG -160 208 0
FLAG 384 -16 0
FLAG -320 272 0
FLAG 0 272 0
FLAG 160 272 0
FLAG -480 208 0
FLAG -1008 -160 0
FLAG 624 -160 0
FLAG 736 -160 0
FLAG 1008 -160 0
FLAG 896 -80 0
FLAG 320 208 0
SYMBOL nmos -48 -224 R270
SYMATTR InstName Q1
SYMATTR Value Si4864DY
SYMBOL res -192 -256 R270
SYMATTR InstName R1
SYMATTR Value 5m
SYMBOL res -608 -256 R0
SYMATTR InstName R2
SYMATTR Value 34K
SYMBOL res -608 0 M180
SYMATTR InstName R3
SYMATTR Value 1.74K
SYMBOL res -608 32 R0
SYMATTR InstName R4
SYMATTR Value 2.67K
SYMBOL res 368 -256 R0
SYMATTR InstName R5
SYMATTR Value 25.1K
SYMBOL res 368 -16 M180
SYMATTR InstName R6
SYMATTR Value 3.57K
SYMBOL res 512 -160 R0
SYMATTR InstName R7
SYMATTR Value 24K
SYMBOL cap -336 192 R0
SYMATTR InstName C1
SYMATTR Value .068
SYMBOL cap -16 192 R0
SYMATTR InstName C2
SYMATTR Value .068
SYMBOL cap 144 192 R0
SYMATTR InstName C3
SYMATTR Value 4
SYMBOL voltage -480 96 R0
SYMATTR InstName V1
SYMATTR Value 3.1
SYMBOL voltage -1008 -272 R0
SYMATTR InstName V2
SYMATTR Value PWL(0 0 10u 0 100u 12 6 12)
SYMBOL cap 608 -256 R0
SYMATTR InstName C4
SYMATTR Value 2000
SYMBOL res 720 -160 M180
SYMATTR InstName R8
SYMATTR Value 10
SYMBOL nmos 816 -224 R270
SYMATTR InstName Q2
SYMATTR Value Si4864DY
SYMBOL voltage 896 -192 R0
SYMATTR InstName V3
SYMATTR Value PWL(0 0 4 0 +100u 12 +200m 12 +100n 0)
SYMBOL res 16 -208 R0
SYMATTR InstName R9
SYMATTR Value 10
SYMBOL res 992 -160 M180
SYMATTR InstName R10
SYMATTR Value .05
SYMBOL voltage 320 96 R0
SYMATTR InstName V4
SYMATTR Value PWL(0 3.1 1 3.1 +100u 0)
SYMBOL PowerProducts\\LTC4215-3 -80 32 R0
SYMATTR InstName U1