Version 4 SHEET 1 888 1240 WIRE -1024 800 -1184 800 WIRE -832 800 -1024 800 WIRE -768 800 -832 800 WIRE -560 800 -768 800 WIRE -1024 816 -1024 800 WIRE -832 816 -832 800 WIRE -768 816 -768 800 WIRE -560 816 -560 800 WIRE -1184 832 -1184 800 WIRE -1024 912 -1024 896 WIRE -960 912 -1024 912 WIRE -832 912 -832 896 WIRE -832 912 -896 912 WIRE -768 912 -768 896 WIRE -736 912 -768 912 WIRE -560 912 -560 896 WIRE -560 912 -672 912 WIRE -368 912 -560 912 WIRE -368 928 -368 912 WIRE -1024 1008 -1024 912 WIRE -560 1008 -560 912 WIRE -832 1056 -768 912 WIRE -832 1056 -960 1056 WIRE -768 1056 -832 912 WIRE -624 1056 -768 1056 WIRE -976 1104 -1024 1104 WIRE -1184 1120 -1184 912 WIRE -1024 1120 -1024 1104 WIRE -976 1120 -976 1104 WIRE -832 1120 -832 1056 WIRE -832 1120 -912 1120 WIRE -768 1120 -768 1056 WIRE -672 1120 -768 1120 WIRE -560 1120 -560 1104 WIRE -560 1120 -608 1120 FLAG -560 1120 0 FLAG -1024 1120 0 FLAG -1184 1120 0 FLAG -368 1088 0 SYMBOL RES -1040 800 R0 SYMATTR InstName R1 SYMATTR Value 1.5K SYMBOL VOLTAGE -1184 816 R0 SYMATTR InstName V1 SYMATTR Value {Vv} SYMBOL NPN -624 1008 R0 SYMATTR InstName Q1 SYMATTR Value 2N3904 SYMBOL npn -960 1008 M0 SYMATTR InstName Q2 SYMATTR Value BC547B SYMBOL RES -848 800 R0 SYMATTR InstName R5 SYMATTR Value 100K SYMBOL RES -784 800 R0 SYMATTR InstName R6 SYMATTR Value 100K SYMBOL RES -576 800 R0 SYMATTR InstName R7 SYMATTR Value 1K SYMBOL cap -896 896 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C3 SYMATTR Value 0.1µ SYMBOL cap -672 896 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 37 30 VTop 2 SYMATTR InstName C4 SYMATTR Value 0.1µ SYMBOL diode -608 1104 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D1 SYMATTR Value 1N4148 SYMBOL diode -976 1136 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value 1N4148 SYMBOL voltage -368 992 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 20 SYMBOL res -384 912 R0 SYMATTR InstName R2 SYMATTR Value 1k TEXT -976 760 Left 2 !.tran 25m startup TEXT -760 1184 Top 1 ;This example schematic is supplied for informational/educational purposes only. TEXT -976 728 Left 2 !.step param Vv list 5V 6V 7V 8V 9V 10V TEXT -296 680 Left 2 ;Absolute max ratings 2N3904 Ta=25 °C\nCharacteristic Symbl Ratings Unit\nCollector-Base voltage VCBO 60 V\nCollector-Emitter voltage VCEO 40 V\nEmitter-base voltage VEBO 6 V\nCollector current IC 200 mA\nCollector dissipation PC 625 mW\nJunction temperature Tj 150 °C\nStorage temperature range Tstg -55~150 C