Version 4 SHEET 1 1224 816 WIRE 432 32 432 0 WIRE 128 96 128 32 WIRE 432 144 432 112 WIRE 432 160 432 144 WIRE 384 192 336 192 WIRE 128 208 128 176 WIRE 128 208 80 208 WIRE 336 224 336 192 WIRE 80 240 80 208 WIRE 128 256 128 208 WIRE 432 272 432 256 WIRE 432 288 432 272 WIRE 128 400 128 336 WIRE 432 416 432 368 FLAG 336 224 0 FLAG 432 0 VDD FLAG 128 32 VDD FLAG 432 144 S FLAG 432 272 D FLAG 432 416 VSS FLAG 80 240 0 FLAG 128 400 VSS SYMBOL voltage 128 80 R0 SYMATTR InstName Vps1 SYMATTR Value 5V SYMBOL res 416 272 R0 SYMATTR InstName RD SYMATTR Value 2k SYMBOL current 432 32 R0 SYMATTR InstName IB SYMATTR Value 1mA SYMBOL pjf 384 256 M180 SYMATTR InstName J1 SYMATTR Value p_jfet SYMBOL voltage 128 240 R0 SYMATTR InstName Vps2 SYMATTR Value 5V TEXT 280 576 Left 2 !.OP TEXT 40 520 Left 2 !.model p_jfet PJF (beta=1m Vto=-2V lambda=0.04)