* 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
R4 N001 N018 3K
R5 0 N018 15.75K
C10 N010 0 100p
C11 N007 N010 .033
R6 N010 0 1K
C12 N001 N015 .1
XU2 N013 MP_01 N007 MP_02 0 N016 MP_03 OUT N009 MP_04 N001 N014 N017 N018 MP_05 N015 LT1620 ;pnba Sense))Iout))GND)Mode))IN-)IN+))Vcc)AVE2)PROG2)PROG))AVE
Rload OUT 0 10
.tran 5m startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1824 1200
WIRE 144 -600 -384 -600
WIRE 320 -600 144 -600
WIRE -160 -584 -592 -584
WIRE 320 -584 320 -600
WIRE -384 -568 -384 -600
WIRE 144 -520 144 -600
WIRE -592 -504 -592 -584
WIRE -560 -504 -592 -504
WIRE -176 -504 -208 -504
WIRE 320 -488 320 -504
WIRE -640 -440 -736 -440
WIRE -560 -440 -576 -440
WIRE 96 -440 -208 -440
WIRE -704 -376 -736 -376
WIRE -560 -376 -640 -376
WIRE 144 -376 144 -424
WIRE 144 -376 -208 -376
WIRE -672 -312 -768 -312
WIRE -560 -312 -672 -312
WIRE -128 -312 -208 -312
WIRE 32 -312 -128 -312
WIRE 144 -312 144 -376
WIRE 144 -312 96 -312
WIRE 224 -312 144 -312
WIRE 368 -312 304 -312
WIRE 384 -312 368 -312
WIRE 480 -312 464 -312
WIRE 560 -312 480 -312
WIRE 656 -312 560 -312
WIRE 800 -312 656 -312
WIRE 912 -312 800 -312
WIRE -768 -296 -768 -312
WIRE 800 -296 800 -312
WIRE 912 -296 912 -312
WIRE 144 -264 144 -312
WIRE -160 -248 -160 -584
WIRE -160 -248 -208 -248
WIRE -128 -248 -160 -248
WIRE 656 -232 656 -312
WIRE -768 -216 -768 -232
WIRE -768 -216 -896 -216
WIRE 560 -216 560 -312
WIRE -896 -200 -896 -216
WIRE -768 -200 -768 -216
WIRE 800 -200 800 -232
WIRE 912 -200 912 -216
WIRE -560 -184 -608 -184
WIRE 96 -184 -208 -184
WIRE -560 -120 -608 -120
WIRE 144 -120 144 -168
WIRE 144 -120 -208 -120
WIRE -896 -104 -896 -136
WIRE -768 -104 -768 -120
WIRE 144 -104 144 -120
WIRE -128 -72 -128 -248
WIRE -80 -72 -128 -72
WIRE 0 -72 -16 -72
WIRE -608 -8 -608 -120
WIRE 560 -8 560 -152
WIRE 560 -8 -608 -8
WIRE 656 -8 656 -152
WIRE 656 -8 560 -8
WIRE -608 8 -608 -8
WIRE 656 8 656 -8
WIRE -480 40 -480 -40
WIRE -416 40 -480 40
WIRE -288 40 -288 -40
WIRE -288 40 -352 40
WIRE -128 40 -128 -72
WIRE -128 40 -288 40
WIRE 96 40 -128 40
WIRE 176 40 96 40
WIRE -608 88 -608 72
WIRE 96 88 96 40
WIRE -128 104 -128 40
WIRE 176 104 176 40
WIRE 656 104 656 88
WIRE -480 168 -480 40
WIRE -304 168 -480 168
WIRE 64 168 48 168
WIRE -672 248 -672 -312
WIRE -304 248 -672 248
WIRE 96 248 96 152
WIRE 96 248 48 248
WIRE -304 328 -320 328
WIRE 64 328 48 328
WIRE 176 408 176 184
WIRE 176 408 48 408
WIRE 192 408 176 408
WIRE 288 408 272 408
WIRE -304 488 -336 488
WIRE 96 488 48 488
WIRE 368 488 368 -312
WIRE 368 488 96 488
WIRE 96 504 96 488
WIRE -128 568 -128 552
WIRE -336 600 -336 488
WIRE 96 600 96 568
WIRE 96 600 -336 600
WIRE 480 600 480 -312
WIRE 480 600 96 600
FLAG 144 -104 0
FLAG -128 568 0
FLAG -608 -184 0
FLAG 0 -72 0
FLAG 800 -200 0
FLAG -736 -440 0
FLAG -736 -376 0
FLAG 320 -488 0
FLAG 656 104 0
FLAG -608 88 0
FLAG 288 408 0
FLAG -896 -104 0
FLAG -768 -104 0
FLAG 912 -200 0
FLAG 912 -312 OUT
FLAG 320 -600 IN
SYMBOL POWERPRODUCTS\\LTC1435A -384 -280 R0
SYMATTR InstName U1
SYMBOL NMOS 96 -264 R0
SYMATTR InstName Q1
SYMATTR Value Si4412DY
SYMBOL nmos 96 -520 R0
SYMATTR InstName Q2
SYMATTR Value Si4412DY
SYMBOL ind 208 -296 R270
SYMATTR InstName L1
SYMATTR Value 27
SYMBOL RES 368 -296 R270
SYMATTR InstName R1
SYMATTR Value 25m
SYMBOL cap 80 504 R0
SYMATTR InstName C1
SYMATTR Value .01
SYMBOL cap -80 -56 R270
SYMATTR InstName C2
SYMATTR Value 4.7
SYMBOL cap -352 24 R90
SYMATTR InstName C3
SYMATTR Value 100p
SYMBOL schottky -144 -248 M180
SYMATTR InstName D1
SYMATTR Value 1N5818
SYMBOL cap 96 -328 R90
SYMATTR InstName C4
SYMATTR Value .1
SYMBOL polcap 784 -296 R0
SYMATTR InstName C5
SYMATTR Value 220
SYMATTR SpiceLine Rser=50m
SYMBOL cap -640 -392 R90
SYMATTR InstName C6
SYMATTR Value .001
SYMBOL cap -576 -456 R90
SYMATTR InstName C7
SYMATTR Value 56p
SYMBOL VOLTAGE 320 -600 R0
SYMATTR InstName V1
SYMATTR Value 23
SYMBOL res 640 -248 R0
SYMATTR InstName R2
SYMATTR Value 1.44Meg
SYMBOL res 640 -8 R0
SYMATTR InstName R3
SYMATTR Value 110K
SYMBOL cap 544 -216 R0
SYMATTR InstName C8
SYMATTR Value 100p
SYMBOL cap -624 8 R0
SYMATTR InstName C9
SYMATTR Value 100p
SYMBOL res 160 88 R0
SYMATTR InstName R4
SYMATTR Value 3K
SYMBOL res 288 392 R90
SYMATTR InstName R5
SYMATTR Value 15.75K
SYMBOL cap -912 -200 R0
SYMATTR InstName C10
SYMATTR Value 100p
SYMBOL cap -784 -296 R0
SYMATTR InstName C11
SYMATTR Value .033
SYMBOL res -784 -216 R0
SYMATTR InstName R6
SYMATTR Value 1K
SYMBOL cap 80 88 R0
SYMATTR InstName C12
SYMATTR Value .1
SYMBOL POWERPRODUCTS\\LT1620 -128 328 R0
SYMATTR InstName U2
SYMBOL res 896 -312 R0
SYMATTR InstName Rload
SYMATTR Value 10