Another design

Now with 9V to 15V input range, direct gate drive and 500mA LED current.

Startup behaviour is not ideal but maybe that can be fixed if it needs
fixing.

What's the cheapest op amp I can use for U2 instead of OP07?

Is there a cheaper comparator instead of LT1719 which will work?
Also the fet is bigger than it needs to ne.

Is there a better device for D4? Particularly if R4 can be reduced.

Will it work at all? Except in simulation.

Version 4
SHEET 1 2820 680
WIRE 1312 -272 0 -272
WIRE 1408 -208 288 -208
WIRE 976 -144 160 -144
WIRE 1088 -144 1040 -144
WIRE -32 -48 -64 -48
WIRE 0 -48 0 -272
WIRE 0 -48 -32 -48
WIRE 48 -48 0 -48
WIRE 240 -48 48 -48
WIRE 336 -48 240 -48
WIRE 448 -48 336 -48
WIRE 464 -48 448 -48
WIRE 528 -48 464 -48
WIRE 608 -48 528 -48
WIRE 672 -48 608 -48
WIRE 800 -48 768 -48
WIRE 816 -48 800 -48
WIRE 864 -48 816 -48
WIRE 992 -48 944 -48
WIRE 1024 -48 992 -48
WIRE 1136 -48 1024 -48
WIRE 240 -16 240 -48
WIRE 336 -16 336 -48
WIRE 1408 -16 1408 -208
WIRE 1136 0 1136 -48
WIRE -64 32 -64 -48
WIRE 448 64 448 -48
WIRE 464 64 464 -48
WIRE 48 80 48 -48
WIRE 160 80 160 -144
WIRE 240 80 240 64
WIRE 240 80 160 80
WIRE 336 80 336 64
WIRE 384 80 336 80
WIRE 416 80 384 80
WIRE 816 80 816 -48
WIRE 992 80 992 -48
WIRE 288 96 288 -208
WIRE 336 96 336 80
WIRE 336 96 288 96
WIRE 656 96 480 96
WIRE 688 96 688 0
WIRE 688 96 656 96
WIRE 240 112 240 80
WIRE 384 112 240 112
WIRE 416 112 384 112
WIRE 528 112 528 -48
WIRE 608 112 608 -48
WIRE 1088 112 1088 -144
WIRE 1136 112 1136 64
WIRE 1136 112 1088 112
WIRE 240 128 240 112
WIRE 336 128 336 96
WIRE -64 176 -64 112
WIRE 1312 192 1312 -272
WIRE 1136 208 1136 112
WIRE 1200 208 1136 208
WIRE 1280 208 1200 208
WIRE 1392 224 1344 224
WIRE 1408 224 1408 64
WIRE 1408 224 1392 224
WIRE 240 240 240 208
WIRE 336 240 336 208
WIRE 336 240 240 240
WIRE 432 240 432 128
WIRE 432 240 336 240
WIRE 448 240 448 128
WIRE 448 240 432 240
WIRE 464 240 464 128
WIRE 464 240 448 240
WIRE 528 240 528 176
WIRE 528 240 464 240
WIRE 608 240 608 176
WIRE 608 240 528 240
WIRE 640 240 608 240
WIRE 752 240 720 240
WIRE 1184 240 752 240
WIRE 1280 240 1184 240
WIRE 1136 256 1136 208
WIRE 752 272 752 240
WIRE -64 368 -64 256
WIRE 48 368 48 144
WIRE 48 368 -64 368
WIRE 752 368 752 336
WIRE 752 368 48 368
WIRE 816 368 816 144
WIRE 816 368 752 368
WIRE 992 368 992 144
WIRE 992 368 816 368
WIRE 1136 368 1136 336
WIRE 1136 368 992 368
WIRE 1312 368 1312 256
WIRE 1312 368 1136 368
WIRE -64 384 -64 368
FLAG -64 384 0
FLAG -32 -48 in
FLAG 800 -48 sw
FLAG 1024 -48 led
FLAG 1200 208 isense
FLAG 1184 240 iref
FLAG 1392 224 ifb
FLAG 384 80 cmp-
FLAG 384 112 cmp+
FLAG 656 96 gate
SYMBOL Comparators\LT1719 448 32 R0
WINDOW 0 27 27 Left 2
WINDOW 3 -92 6 Left 2
SYMATTR InstName U1
SYMBOL res 320 112 R0
WINDOW 0 41 34 Left 2
WINDOW 3 35 64 Left 2
SYMATTR InstName R2
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL ind 960 -64 R90
WINDOW 0 63 51 VBottom 2
WINDOW 3 -27 53 VTop 2
SYMATTR InstName L1
SYMATTR Value 100�
SYMATTR SpiceLine Ipk=1.3 Rser=0.15 Rpar=0 Cpar=0
SYMBOL res 1120 240 R0
WINDOW 0 40 39 Left 2
WINDOW 3 39 70 Left 2
SYMATTR InstName R4
SYMATTR Value 1.5
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 224 -32 R0
WINDOW 0 -35 19 Left 2
WINDOW 3 -45 46 Left 2
SYMATTR InstName R3
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL schottky 832 144 R180
WINDOW 0 -45 30 Left 2
WINDOW 3 -127 -3 Left 2
SYMATTR InstName D2
SYMATTR Value MBRS130L
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL pmos 768 0 M270
WINDOW 0 25 128 VLeft 2
WINDOW 3 69 92 VLeft 2
SYMATTR InstName M1
SYMATTR Value AO6407
SYMBOL voltage -64 160 R0
WINDOW 0 11 100 Left 2
WINDOW 3 38 54 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 -185 81 Left 2
SYMATTR InstName V3
SYMATTR Value 12
SYMBOL res -80 16 R0
SYMATTR InstName R8
SYMATTR Value 0.001
SYMBOL zener 544 176 R180
WINDOW 0 37 29 Left 2
WINDOW 3 68 -5 Right 2
SYMATTR InstName D1
SYMATTR Value UMZ5_1N
SYMBOL res 320 -32 R0
WINDOW 0 40 7 Left 2
WINDOW 3 37 33 Left 2
SYMATTR InstName R1
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 736 224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 220
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL cap 592 176 M180
WINDOW 0 39 47 Left 2
WINDOW 3 37 16 Left 2
SYMATTR InstName C3
SYMATTR Value 0.1�
SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0337 Lser=180p
SYMBOL polcap 976 80 R0
WINDOW 3 24 56 Left 2
WINDOW 0 27 9 Left 2
SYMATTR Value 100�
SYMATTR InstName C1
SYMATTR Description Capacitor
SYMATTR Type cap
SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0
SYMBOL res 224 112 R0
WINDOW 0 -40 36 Left 2
WINDOW 3 -49 65 Left 2
SYMATTR InstName R5
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL polcap 32 80 R0
WINDOW 3 24 56 Left 2
WINDOW 0 27 9 Left 2
SYMATTR Value 100�
SYMATTR InstName C2
SYMATTR Description Capacitor
SYMATTR Type cap
SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0
SYMBOL LED 1120 0 R0
SYMATTR InstName D3
SYMATTR Value LXZ1-PB01
SYMBOL res 1424 80 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R9
SYMATTR Value 22K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL cap 976 -160 M90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C5
SYMATTR Value 0.01�
SYMATTR SpiceLine V=16 Irms=291m Rser=0.34258 Lser=0 mfg="KEMET"
pn="C0805F103K4RAC" type="X7R"
SYMBOL OpAmps\OP07 1312 160 R0
SYMATTR InstName U2
SYMBOL diode 736 272 R0
WINDOW 0 -40 38 Left 2
WINDOW 3 -84 70 Left 2
SYMATTR InstName D4
SYMATTR Value 1N4148
TEXT -144 432 Left 2 !.tran 0.01 startup