Version 4
SHEET 1 928 680
WIRE 128 -64 -288 -64
WIRE 480 -64 128 -64
WIRE 656 -64 480 -64
WIRE 480 -32 480 -64
WIRE -288 80 -288 -64
WIRE 480 80 480 48
WIRE 128 128 128 -64
WIRE 96 144 64 144
WIRE 256 160 160 160
WIRE 304 160 256 160
WIRE 432 160 384 160
WIRE 656 160 656 -64
WIRE 96 176 32 176
WIRE 256 176 256 160
WIRE -288 224 -288 160
WIRE -48 224 -288 224
WIRE -288 256 -288 224
WIRE 64 256 64 144
WIRE 256 256 256 240
WIRE 256 256 64 256
WIRE 304 256 256 256
WIRE 480 256 480 176
WIRE 480 256 384 256
WIRE -48 288 -48 224
WIRE 480 288 480 256
WIRE 32 336 32 176
WIRE 32 336 0 336
WIRE -288 400 -288 320
WIRE -48 400 -48 368
WIRE -48 400 -288 400
WIRE 128 400 128 192
WIRE 128 400 -48 400
WIRE 480 400 480 368
WIRE 480 400 128 400
WIRE 656 400 656 240
WIRE 656 400 480 400
WIRE 480 448 480 400
FLAG 480 448 0
SYMBOL res 464 272 R0
SYMATTR InstName R1
SYMATTR Value 27
SYMBOL res 288 144 M90
WINDOW 0 0 56 VBottom 2
WINDOW 3 29 60 VTop 2
SYMATTR InstName R3
SYMATTR Value 470
SYMBOL voltage 656 144 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 26
SYMBOL res 464 -48 R0
SYMATTR InstName RL
SYMATTR Value 100
SYMBOL References\\LT1634-2.5 -288 288 R0
SYMATTR InstName U2
SYMBOL nmos 432 80 R0
SYMATTR InstName M2
SYMATTR Value Si4404DY
SYMBOL potentiometer -64 272 R0
WINDOW 3 -74 149 Left 2
SYMATTR Value Rtot=5K wiper={w}
SYMATTR InstName U4
SYMBOL res -304 64 R0
SYMATTR InstName R2
SYMATTR Value 22k
SYMBOL res 288 240 M90
WINDOW 0 0 56 VBottom 2
WINDOW 3 29 60 VTop 2
SYMATTR InstName R5
SYMATTR Value 2200
SYMBOL cap 240 176 R0
SYMATTR InstName C1
SYMATTR Value 1n
SYMBOL Opamps\\LT1013 128 96 R0
SYMATTR InstName U1
TEXT -304 464 Left 2 !.op
TEXT -304 496 Left 2 !.step param w 0 1 0.1
TEXT -304 552 Left 2 !.lib potentiometer.sub
TEXT 0 496 Left 2 ;.options gminsteps=0
TEXT 144 224 Left 2 ;LM358
TEXT -304 592 Left 2 ;.lib LM358.mod
TEXT 408 -24 Left 2 ;Last
RECTANGLE Normal 576 64 384 -48 2