"Bill Sloman" snipped-for-privacy@ieee.org wrote in message news:10qsnim$15pr5$ snipped-for-privacy@dont-email.me...
Ok please make an equivalent of this but to your design standards and low cost. Note that I'm not asking for criticism of this circuit. There are many reasons why reality may not be the same as its simulation but I had fun doing it. If it doesn't give a constant current of 500mA, open it in Notepad++ Under Encoding, convert to ANSI and save it.
Version 4.1 SHEET 1 2820 680 WIRE 976 -128 272 -128 WIRE 1072 -128 1040 -128 WIRE 16 -48 -16 -48 WIRE 96 -48 16 -48 WIRE 240 -48 96 -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 784 -48 768 -48 WIRE 816 -48 784 -48 WIRE 864 -48 816 -48 WIRE 992 -48 944 -48 WIRE 1024 -48 992 -48 WIRE 1072 -48 1072 -128 WIRE 1072 -48 1024 -48 WIRE 1264 -48 1072 -48 WIRE 1360 -48 1264 -48 WIRE 240 -16 240 -48 WIRE 336 -16 336 -48 WIRE 1264 0 1264 -48 WIRE 1360 0 1360 -48 WIRE -16 32 -16 -48 WIRE 608 32 608 -48 WIRE 1168 32 608 32 WIRE 448 64 448 -48 WIRE 464 64 464 -48 WIRE 96 80 96 -48 WIRE 240 80 240 64 WIRE 272 80 272 -128 WIRE 272 80 240 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 1168 80 1168 32 WIRE 336 96 336 80 WIRE 336 96 304 96 WIRE 656 96 480 96 WIRE 688 96 688 0 WIRE 688 96 656 96 WIRE 1232 96 1200 96 WIRE 1264 96 1264 64 WIRE 1264 96 1232 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 32 WIRE 1104 112 1088 112 WIRE 1136 112 1104 112 WIRE 240 128 240 112 WIRE 336 128 336 96 WIRE 1312 128 1200 128 WIRE 1360 128 1360 80 WIRE 1360 128 1312 128 WIRE 1360 160 1360 128 WIRE -16 176 -16 112 WIRE 240 240 240 208 WIRE 336 240 336 208 WIRE 336 240 240 240 WIRE 384 240 336 240 WIRE 432 240 432 128 WIRE 432 240 384 240 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 544 240 528 240 WIRE 608 240 608 176 WIRE 608 240 544 240 WIRE 1360 240 1360 224 WIRE 1424 240 1360 240 WIRE 1536 240 1424 240 WIRE 1696 240 1600 240 WIRE 1872 240 1760 240 WIRE 544 272 544 240 WIRE 1264 272 1264 96 WIRE 1360 272 1360 240 WIRE -16 368 -16 256 WIRE 96 368 96 144 WIRE 96 368 -16 368 WIRE 544 368 544 352 WIRE 544 368 96 368 WIRE 816 368 816 144 WIRE 816 368 544 368 WIRE 992 368 992 144 WIRE 992 368 816 368 WIRE 1168 368 1168 144 WIRE 1168 368 992 368 WIRE 1264 368 1264 352 WIRE 1264 368 1168 368 WIRE 1360 368 1360 336 WIRE 1360 368 1264 368 WIRE 1872 368 1872 240 WIRE 1872 368 1360 368 WIRE -16 384 -16 368 WIRE 304 448 304 96 WIRE 992 448 304 448 WIRE 1088 448 1088 112 WIRE 1088 448 1072 448 FLAG -16 384 0 FLAG 16 -48 in FLAG 784 -48 sw FLAG 1024 -48 out FLAG 1312 128 isense FLAG 1232 96 iref FLAG 1104 112 ifb FLAG 384 80 cmp- FLAG 384 112 cmp+ FLAG 656 96 gate FLAG 384 240 cmpv- FLAG 1424 240 led 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 R4 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 0.068m SYMATTR SpiceLine Ipk=0.85 Rser=0.21 Rpar=0 Cpar=0 SYMBOL res 1376 -16 M0 WINDOW 0 -37 34 Left 2 WINDOW 3 -57 63 Left 2 SYMATTR InstName R8 SYMATTR Value 0.68 SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL res 224 -32 R0 WINDOW 0 -35 19 Left 2 WINDOW 3 -49 48 Left 2 SYMATTR InstName R1 SYMATTR Value 10K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL schottky 832 144 R180 WINDOW 0 -42 30 Left 2 WINDOW 3 -119 -3 Left 2 SYMATTR InstName D2 SYMATTR Value MBRS130L SYMATTR Description Diode SYMATTR Type diode SYMBOL pmos 768 0 M270 WINDOW 0 10 129 VLeft 2 WINDOW 3 -10 67 VLeft 2 SYMATTR InstName M1 SYMATTR Value AO6407 SYMBOL voltage -16 160 R0 WINDOW 0 -75 16 Left 2 WINDOW 3 -71 54 Left 2 WINDOW 123 0 0 Left 0 WINDOW 39 -185 81 Left 2 SYMATTR InstName V3 SYMATTR Value 12 SYMBOL res -32 16 R0 WINDOW 0 -39 29 Left 2 WINDOW 3 -63 65 Left 2 SYMATTR InstName R9 SYMATTR Value 0.001 SYMBOL zener 544 176 R180 WINDOW 0 37 29 Left 2 WINDOW 3 78 -5 Right 2 SYMATTR InstName D1 SYMATTR Value BZX84C6V2L SYMBOL res 320 -32 R0 WINDOW 0 40 7 Left 2 WINDOW 3 37 33 Left 2 SYMATTR InstName R3 SYMATTR Value 10K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL res 528 368 M180 WINDOW 0 39 76 Left 2 WINDOW 3 38 42 Left 2 SYMATTR InstName R5 SYMATTR Value 220 SYMATTR SpiceLine tol=1 pwr=0.25 SYMBOL cap 592 176 M180 WINDOW 0 29 52 Left 2 WINDOW 3 30 13 Left 2 SYMATTR InstName C3 SYMATTR Value 100n SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.0337 Lser=180p mfg="Würth Elektronik" pn="885012104009 WCAP-CSGP 0201" type="X5R" SYMBOL polcap 976 80 R0 WINDOW 3 -11 59 Left 2 WINDOW 0 27 9 Left 2 SYMATTR Value 100000n SYMATTR InstName C1 SYMATTR Description Capacitor SYMATTR Type cap SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0 mfg="AVX" pn="TAJD107M006" type="Tantalum" SYMBOL res 224 112 R0 WINDOW 0 -40 33 Left 2 WINDOW 3 -52 57 Left 2 SYMATTR InstName R2 SYMATTR Value 10K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL polcap 80 80 R0 WINDOW 3 -27 60 Left 2 WINDOW 0 -39 4 Left 2 SYMATTR Value 100000n SYMATTR InstName C2 SYMATTR Description Capacitor SYMATTR Type cap SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0 mfg="AVX" pn="TAJD107M006" type="Tantalum" SYMBOL LED 1536 256 R270 WINDOW 0 72 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName LED1 SYMATTR Value LXZ1-PB01 SYMBOL res 976 432 M90 WINDOW 0 -2 59 VBottom 2 WINDOW 3 35 64 VTop 2 SYMATTR InstName R6 SYMATTR Value 22K SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL cap 976 -144 M90 WINDOW 0 -3 31 VBottom 2 WINDOW 3 36 35 VTop 2 SYMATTR InstName C5 SYMATTR Value 10n SYMATTR SpiceLine V=16 Irms=0 Rser=0.0747 Lser=525p mfg="Würth Elektronik" pn="885012210001 WCAP-CSGP 1812" type="X7R" SYMBOL OpAmps\\OP07 1168 48 M0 WINDOW 0 12 22 Left 2 WINDOW 3 9 103 Left 2 SYMATTR InstName U2 SYMBOL res 1248 368 M180 WINDOW 0 -40 81 Left 2 WINDOW 3 -51 46 Left 2 SYMATTR InstName R7 SYMATTR Value 470 SYMATTR SpiceLine tol=1 pwr=0.1 SYMBOL schottky 1280 0 M0 WINDOW 0 43 24 Left 2 WINDOW 3 40 -8 Left 2 SYMATTR InstName D3 SYMATTR Value BAT54AHY SYMATTR Description Diode SYMATTR Type diode SYMBOL FerriteBead 1360 192 R0 SYMATTR InstName L2 SYMATTR Value 6µ SYMATTR SpiceLine Ipk=3 Rser=0.0102 Rpar=1220 Cpar=1.9p SYMBOL cap 1344 272 R0 SYMATTR InstName C4 SYMATTR Value 1n SYMATTR SpiceLine V=10 Irms=0 Rser=0.1909 Lser=177p mfg="Würth Elektronik" pn="885012205006 WCAP-CSGP 0402" type="X7R" SYMBOL LED 1696 256 R270 WINDOW 0 72 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName LED2 SYMATTR Value LXZ1-PB01 TEXT -24 440 Left 2 !.tran 0 0.001 0 1u startup TEXT -24 480 Left 2 !.options plotwinsize=0