Version 4 SHEET 1 1068 692 WIRE -320 112 -320 80 WIRE -320 272 -320 192 WIRE -320 336 -320 272 WIRE -320 480 -320 416 WIRE -192 400 -192 320 WIRE -160 272 -320 272 WIRE -160 320 -192 320 WIRE -112 256 -112 224 WIRE -112 368 -112 336 WIRE -64 -368 -64 -416 WIRE -64 -240 -64 -288 WIRE 0 224 -112 224 WIRE 0 288 0 224 WIRE 0 400 -192 400 WIRE 0 400 0 352 WIRE 48 224 0 224 WIRE 64 -416 -64 -416 WIRE 64 -288 64 -416 WIRE 64 -160 64 -208 WIRE 64 -48 64 -160 WIRE 64 -32 64 -48 WIRE 64 80 -320 80 WIRE 64 80 64 48 WIRE 80 400 0 400 WIRE 112 -416 64 -416 WIRE 128 80 64 80 WIRE 128 112 128 80 WIRE 128 224 112 224 WIRE 128 224 128 192 WIRE 160 224 128 224 WIRE 224 -416 112 -416 WIRE 224 -288 224 -416 WIRE 224 -160 64 -160 WIRE 224 -160 224 -192 WIRE 224 -48 64 -48 WIRE 224 -16 224 -48 WIRE 224 80 128 80 WIRE 224 80 224 48 WIRE 224 176 224 80 WIRE 224 400 160 400 WIRE 224 400 224 272 WIRE 256 592 256 544 WIRE 256 672 256 656 WIRE 320 -160 224 -160 WIRE 336 400 224 400 WIRE 384 -416 224 -416 WIRE 384 -384 384 -416 WIRE 384 -240 288 -240 WIRE 384 -240 384 -304 WIRE 384 -208 384 -240 WIRE 384 400 336 400 WIRE 384 400 384 -112 WIRE 384 432 384 400 WIRE 384 544 256 544 WIRE 384 544 384 512 WIRE 384 560 384 544 WIRE 384 672 384 640 FLAG -320 480 0 FLAG 384 672 0 FLAG -64 -240 0 FLAG 112 -416 vcc FLAG 256 672 0 FLAG -112 368 0 FLAG 336 400 out SYMBOL npn 160 176 R0 SYMATTR InstName Q1 SYMBOL current -320 112 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName I1 SYMATTR Value 10m SYMBOL res 48 -304 R0 SYMATTR InstName R2 SYMATTR Value {R1} SYMBOL pnp 288 -192 R180 SYMATTR InstName Q3 SYMBOL pnp 320 -112 M180 SYMATTR InstName Q4 SYMBOL res 368 -400 R0 SYMATTR InstName R3 SYMATTR Value {Rsc} SYMBOL battery -64 -384 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 10 SYMBOL current 384 560 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName Iload SYMATTR Value 0 SYMBOL diode 272 656 R180 WINDOW 0 24 72 Left 0 WINDOW 3 24 0 Left 0 SYMATTR InstName D2 SYMATTR Value DIdeal SYMBOL current 64 -32 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName I3 SYMATTR Value 1 SYMBOL diode 240 48 R180 WINDOW 0 24 72 Left 0 WINDOW 3 24 0 Left 0 SYMATTR InstName D3 SYMBOL battery -320 320 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value 5 SYMBOL e -112 240 R0 SYMATTR InstName E1 SYMATTR Value 1e6 SYMBOL diode 112 208 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName D4 SYMBOL res 112 96 R0 SYMATTR InstName R1 SYMATTR Value 100 SYMBOL diode -16 288 R0 SYMATTR InstName D5 SYMBOL res 176 384 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R5 SYMATTR Value 1e9 SYMBOL battery 384 416 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName Vsense SYMATTR Value 0 TEXT 480 -344 Left 0 !.param R1=2.2 TEXT 480 -296 Left 0 !.param Rsc=0.228 TEXT 480 -248 Left 0 !.dc Iload 100m 10 10m TEXT 480 -384 Left 0 !.model DIdeal D(Ron=.01 Roff=100Meg Vfwd=0) TEXT -160 432 Left 0 ;7805 Macromodel TEXT -216 -88 Left 0 ;I3 sets the 7805\ncurrent limit to 1 Amp TEXT -392 24 Left 0 ;D3 provides a path for excess I3 when\nless than 1 amp is flowing through Q1 TEXT -152 600 Left 0 ;D2 provides a path for I2 when\nthe regulator current limits TEXT 440 464 Left 0 ;Vsense provides a device through \nwhich to measure the current TEXT -248 112 Left 0 ;D4 and D5 prevent E1 output \nfrom going to 5 zillion volts \nwhen the 1 amp limit is reached TEXT 416 -96 Left 0 ;The default transistor models \nconveniently have a default beta of 100 TEXT 496 248 Left 0 ;Don't try to use this in \na transient simulation \nand expect to get realistic results RECTANGLE Normal 288 464 -400 -112 2 RECTANGLE Normal 864 320 480 224 RECTANGLE Normal 864 320 480 224 RECTANGLE Normal 880 336 464 208