* Z:\home\khalils\Downloads\files\data\raw_asc\LT1681.asc
* Generated by LTspice 26.0.1 for Windows.
* Library below included based on ModelFile attribute of instance XU1 (C:\users\khalils\AppData\Local\LTspice\lib\sym\PowerProducts\LT1681.asy)
V1 IN 0 16
R1 N012 0 25m
R2 N015 N013 100
D3 IN N001 1N5817
L3 N004 OUT 10
D2 N003 N004 MBRS360
C2 N016 N015 .001
MQ2 N009 N006 N012 N012 IRF7303
K1 L1 L2 1.
L1 N005 N009 300
L2 N003 0 300
R3 N013 0 1K
C3 N007 0 150p
C4 OUT 0 100 Rser=50m
D1 0 N004 MBRS360
C1 N010 0 .001
Rload OUT 0 .5
XU1 IN 0 0 0 N008 N007 MP_01 N010 N013 N016 N012 N014 N011 IN 0 N006 N006 N005 N002 N001 LT1681 ;pnba _SHDN)OVLO)TERM)GSND)5Vref)FSET))SS)FB)Vc)Sense)Imax)SG)Vcc)PGND)GB)BLKSENS)BSTREF)TG)Vbst
R5 N008 N007 52.3K
C5 N005 N001 .5
R4 N013 OUT 1K
MQ1 IN N002 N005 N005 IRF7303
.model D D
.lib C:\users\khalils\AppData\Local\LTspice\lib\cmp\standard.dio
.model NMOS NMOS
.model PMOS PMOS
.lib C:\users\khalils\AppData\Local\LTspice\lib\cmp\standard.mos
.tran 500u startup
.lib LT1681.sub
.backanno
.end

* LTspice schematic (.asc):
Version 4
SHEET 1 1480 712
WIRE 208 64 112 64
WIRE 576 64 208 64
WIRE 608 64 576 64
WIRE 848 64 608 64
WIRE 112 80 112 64
WIRE 848 96 848 64
WIRE 208 128 208 64
WIRE 240 128 208 128
WIRE 608 128 528 128
WIRE 672 128 608 128
WIRE 112 176 112 160
WIRE 240 176 224 176
WIRE 800 176 528 176
WIRE 960 208 896 208
WIRE 1072 208 1024 208
WIRE 1088 208 1072 208
WIRE 1216 208 1168 208
WIRE 1264 208 1216 208
WIRE 1360 208 1264 208
WIRE 240 224 224 224
WIRE 736 224 736 128
WIRE 736 224 528 224
WIRE 848 224 848 192
WIRE 848 224 736 224
WIRE 1264 224 1264 208
WIRE 1360 224 1360 208
WIRE 848 240 848 224
WIRE 896 240 896 208
WIRE 1072 256 1072 208
WIRE 240 272 224 272
WIRE 544 272 528 272
WIRE 128 320 96 320
WIRE 240 320 208 320
WIRE 544 320 544 272
WIRE 544 320 528 320
WIRE 704 320 544 320
WIRE 1264 320 1264 288
WIRE 1360 320 1360 304
WIRE 848 336 848 320
WIRE 896 352 896 320
WIRE 1072 352 1072 320
WIRE 0 368 -32 368
WIRE 96 368 96 320
WIRE 96 368 64 368
WIRE 240 368 96 368
WIRE 544 368 528 368
WIRE 576 416 576 64
WIRE 576 416 528 416
WIRE 704 416 704 320
WIRE 800 416 704 416
WIRE 144 464 128 464
WIRE 240 464 208 464
WIRE 544 464 528 464
WIRE 848 464 848 432
WIRE 848 464 784 464
WIRE 848 480 848 464
WIRE 1216 496 1216 208
WIRE -64 512 -80 512
WIRE 32 512 16 512
WIRE 240 512 32 512
WIRE 544 512 528 512
WIRE 32 560 32 512
WIRE 48 560 32 560
WIRE 160 560 128 560
WIRE 240 560 224 560
WIRE 784 560 784 464
WIRE 784 560 528 560
WIRE 848 576 848 560
WIRE 32 624 32 560
WIRE 1216 624 1216 576
WIRE 1216 624 32 624
SYMBOL voltage 112 64 R0
SYMATTR InstName V1
SYMATTR Value 16
SYMBOL schottky 592 64 R0
WINDOW 0 36 19 Left 2
WINDOW 3 -11 88 Left 2
SYMATTR InstName D3
SYMATTR Value 1N5817
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 208 448 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value .001
SYMBOL ind 1072 224 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName L3
SYMATTR Value 10
SYMBOL PowerProducts\\LT1681 384 336 R0
SYMATTR InstName U1
SYMBOL res 1344 208 R0
SYMATTR InstName Rload
SYMATTR Value .5
SYMBOL cap 64 352 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C3
SYMATTR Value 150p
SYMBOL cap 224 544 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value .001
SYMBOL schottky 1056 320 M180
WINDOW 0 24 72 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value MBRS360
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL nmos 800 336 R0
WINDOW 0 -1 24 Right 2
WINDOW 3 42 103 Right 2
SYMATTR InstName Q2
SYMATTR Value IRF7303
SYMBOL ind2 912 224 M0
WINDOW 0 -4 31 Right 2
WINDOW 3 -6 71 Right 2
SYMATTR InstName L2
SYMATTR Value 300
SYMATTR Type ind
SYMBOL res 32 496 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 1K
SYMBOL cap 736 112 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C5
SYMATTR Value .5
SYMBOL ind2 832 224 R0
WINDOW 0 -4 31 Right 2
WINDOW 3 -6 71 Right 2
SYMATTR InstName L1
SYMATTR Value 300
SYMATTR Type ind
SYMBOL res 224 304 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R5
SYMATTR Value 52.3K
SYMBOL nmos 800 96 R0
WINDOW 0 -2 23 Right 2
WINDOW 3 40 102 Right 2
SYMATTR InstName Q1
SYMATTR Value IRF7303
SYMBOL res 1200 592 M180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R4
SYMATTR Value 1K
SYMBOL cap 1248 224 R0
SYMATTR InstName C4
SYMATTR Value 100
SYMATTR SpiceLine Rser=50m
SYMBOL schottky 960 224 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D2
SYMATTR Value MBRS360
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 832 464 R0
SYMATTR InstName R1
SYMATTR Value 25m
SYMBOL res 144 544 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 100
FLAG 544 368 0
FLAG 848 576 0
FLAG 224 272 0
FLAG 224 224 0
FLAG 224 176 0
FLAG 128 464 0
FLAG -32 368 0
FLAG 112 176 0
FLAG 1264 320 0
FLAG -80 512 0
FLAG 1360 320 0
FLAG 896 352 0
FLAG 1072 352 0
FLAG 1360 208 OUT
FLAG 112 64 IN
TEXT 792 32 Left 2 !K1 L1 L2 1.
TEXT 568 672 Left 2 !.tran 500u startup