Brightness Control for 1.5v bulbs


Lots of people ask about low voltage brightness control circuits so i believe this can be very useful circuit for you.I suppose you can use this for various purposes.So try this circuit...







Parts:

Q1 BD681 100V 4A NPN Darlington Transistor

P1 470K Linear Potentiometer

C1 22nF 63V Polyester Capacitor

C2 100µF 25V Electrolytic Capacitor

D1,D2 1N4148 75V 150mA Diodes

IC1 7555 or TS555CN CMos Timer IC

R1 10K 1/4W Resistor

R2 47K 1/4W Resistor

R3 1K5 1/4W Resistor

LP1 1.5V 200mA Bulb

SW1 SPST Switch

B1 3V (Two 1.5V AA or AAA cells in series, etc.)

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