* SPICE netlist
XU1 N003 N005 N007 N001 0 N012 N013 N001 N002 0 N011 N001 IN N006 N008 N004 LTC1435A ;pnba OSC)SOFT)Ith)SFB)SGND)Vosense)SEN-)SEN+)ExtVcc)PGND)BG)IntVcc)Vin)SW)Boost)TG
MQ1 N006 N011 0 0 Si4412DY
MQ2 IN N004 N006 N006 Si4412DY
L1 N006 N009 27
R1 N009 OUT 25m
C1 N009 OUT .01
C2 N001 0 4.7
C3 N001 N013 100p
D1 N001 N008 1N5818
C4 N006 N008 .1
C5 OUT 0 220 Rser=50m
C6 N005 0 .001
C7 N003 0 56p
V1 IN 0 23
R2 OUT N012 1.44Meg
R3 N012 0 110K
C8 OUT N012 100p
C9 N012 0 100p
C10 N010 0 100p
C11 N007 N010 .033
R4 N010 0 1K
C12 N001 N015 .1
R5 OUT 0 10
XU2 N014 NC_01 N013 N007 NC_02 NC_03 NC_04 NC_05 NC_06 N015 NC_07 NC_08 0 OUT N009 N001 LT1621 ;pnba PROG A)AVE A)Sense A)Iout A)GND B)IN- B)IN+ B)Vcc B)PROG B)AVE B)Sense B)Iout B)GND A)IN- A)IN+ A)Vcc A
R6 0 N014 15.75K
R7 N001 N014 3K
.tran 5m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1728 1344
WIRE 192 -672 -336 -672
WIRE 368 -672 192 -672
WIRE -112 -656 -544 -656
WIRE 368 -656 368 -672
WIRE -336 -640 -336 -672
WIRE 192 -592 192 -672
WIRE -544 -576 -544 -656
WIRE -512 -576 -544 -576
WIRE -128 -576 -160 -576
WIRE 368 -560 368 -576
WIRE -592 -512 -688 -512
WIRE -512 -512 -528 -512
WIRE 144 -512 -160 -512
WIRE -656 -448 -688 -448
WIRE -512 -448 -592 -448
WIRE 192 -448 192 -496
WIRE 192 -448 -160 -448
WIRE -624 -384 -720 -384
WIRE -512 -384 -624 -384
WIRE -80 -384 -160 -384
WIRE 80 -384 -80 -384
WIRE 192 -384 192 -448
WIRE 192 -384 144 -384
WIRE 224 -384 192 -384
WIRE 336 -384 304 -384
WIRE 352 -384 336 -384
WIRE 448 -384 432 -384
WIRE 512 -384 448 -384
WIRE 608 -384 512 -384
WIRE 752 -384 608 -384
WIRE 864 -384 752 -384
WIRE -720 -368 -720 -384
WIRE 752 -368 752 -384
WIRE 864 -368 864 -384
WIRE 192 -336 192 -384
WIRE -112 -320 -112 -656
WIRE -112 -320 -160 -320
WIRE -80 -320 -112 -320
WIRE 608 -304 608 -384
WIRE -720 -288 -720 -304
WIRE -720 -288 -848 -288
WIRE 512 -288 512 -384
WIRE -848 -272 -848 -288
WIRE -720 -272 -720 -288
WIRE 752 -272 752 -304
WIRE 864 -272 864 -288
WIRE -512 -256 -560 -256
WIRE 144 -256 -160 -256
WIRE -512 -192 -560 -192
WIRE 192 -192 192 -240
WIRE 192 -192 -160 -192
WIRE -848 -176 -848 -208
WIRE -720 -176 -720 -192
WIRE 192 -176 192 -192
WIRE -80 -160 -80 -320
WIRE -32 -160 -80 -160
WIRE -32 -144 -32 -160
WIRE -32 -64 -32 -80
WIRE -560 -32 -560 -192
WIRE 512 -32 512 -224
WIRE 512 -32 -560 -32
WIRE 608 -32 608 -224
WIRE 608 -32 512 -32
WIRE -560 -16 -560 -32
WIRE 608 -16 608 -32
WIRE -432 48 -432 -112
WIRE -368 48 -432 48
WIRE -240 48 -240 -112
WIRE -240 48 -304 48
WIRE -128 48 -240 48
WIRE -80 48 -80 -160
WIRE -80 48 -128 48
WIRE 64 48 -80 48
WIRE 144 48 64 48
WIRE -560 64 -560 48
WIRE 608 80 608 64
WIRE -272 96 -352 96
WIRE -128 96 -128 48
WIRE -128 96 -192 96
WIRE 144 96 144 48
WIRE -560 192 -576 192
WIRE -352 192 -352 96
WIRE -352 192 -480 192
WIRE -320 192 -352 192
WIRE 64 192 64 48
WIRE 64 192 32 192
WIRE 64 272 32 272
WIRE 336 272 336 -384
WIRE 336 272 64 272
WIRE -432 352 -432 48
WIRE -320 352 -432 352
WIRE 64 352 64 336
WIRE 64 352 32 352
WIRE 448 352 448 -384
WIRE 448 352 64 352
WIRE -624 432 -624 -384
WIRE -320 432 -624 432
WIRE 80 432 32 432
WIRE 144 672 144 160
WIRE 144 672 32 672
FLAG 192 -176 0
FLAG -560 -256 0
FLAG -32 -64 0
FLAG 752 -272 0
FLAG -688 -512 0
FLAG -688 -448 0
FLAG 368 -560 0
FLAG 608 80 0
FLAG -560 64 0
FLAG -848 -176 0
FLAG -720 -176 0
FLAG 864 -272 0
FLAG 864 -384 OUT
FLAG -576 192 0
FLAG 80 432 0
FLAG 368 -672 IN
SYMBOL POWERPRODUCTS\\LTC1435A -336 -352 R0
SYMATTR InstName U1
SYMBOL NMOS 144 -336 R0
SYMATTR InstName Q1
SYMATTR Value Si4412DY
SYMBOL nmos 144 -592 R0
SYMATTR InstName Q2
SYMATTR Value Si4412DY
SYMBOL ind 208 -368 R270
SYMATTR InstName L1
SYMATTR Value 27
SYMBOL RES 336 -368 R270
SYMATTR InstName R1
SYMATTR Value 25m
SYMBOL cap 48 272 R0
SYMATTR InstName C1
SYMATTR Value .01
SYMBOL cap -48 -144 R0
SYMATTR InstName C2
SYMATTR Value 4.7
SYMBOL cap -304 32 R90
SYMATTR InstName C3
SYMATTR Value 100p
SYMBOL schottky -96 -320 M180
SYMATTR InstName D1
SYMATTR Value 1N5818
SYMBOL cap 144 -400 R90
SYMATTR InstName C4
SYMATTR Value .1
SYMBOL polcap 736 -368 R0
SYMATTR InstName C5
SYMATTR Value 220
SYMATTR SpiceLine Rser=50m
SYMBOL cap -592 -464 R90
SYMATTR InstName C6
SYMATTR Value .001
SYMBOL cap -528 -528 R90
SYMATTR InstName C7
SYMATTR Value 56p
SYMBOL VOLTAGE 368 -672 R0
SYMATTR InstName V1
SYMATTR Value 23
SYMBOL res 592 -320 R0
SYMATTR InstName R2
SYMATTR Value 1.44Meg
SYMBOL res 592 -32 R0
SYMATTR InstName R3
SYMATTR Value 110K
SYMBOL cap 496 -288 R0
SYMATTR InstName C8
SYMATTR Value 100p
SYMBOL cap -576 -16 R0
SYMATTR InstName C9
SYMATTR Value 100p
SYMBOL cap -864 -272 R0
SYMATTR InstName C10
SYMATTR Value 100p
SYMBOL cap -736 -368 R0
SYMATTR InstName C11
SYMATTR Value .033
SYMBOL res -736 -288 R0
SYMATTR InstName R4
SYMATTR Value 1K
SYMBOL cap 128 96 R0
SYMATTR InstName C12
SYMATTR Value .1
SYMBOL res 848 -384 R0
SYMATTR InstName R5
SYMATTR Value 10
SYMBOL PowerProducts\\LT1621 -144 512 R0
SYMATTR InstName U2
SYMBOL res -576 208 R270
SYMATTR InstName R6
SYMATTR Value 15.75K
SYMBOL res -176 80 R90
SYMATTR InstName R7
SYMATTR Value 3K