Circuit apparatus for driving light emitting diode with low voltage
AssigneePrecision Instrument Development Center
InventorTai Shan Liao
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Abstract
A circuit apparatus for driving a light emitting diode with a low voltage is disclosed. The circuit apparatus includes an NPN transistor, a PNP transistor, a capacitor connected to a base of the NPN transistor, a resistor connected to a contact point between the base of the NPN transistor and the capacitor and connected to the power, and an inductor connected to the power ground and a collector of the PNP transistor.
Claims5
A circuit apparatus for driving a light emitting diode (LED) and being energized by a power source, comprising:
- a first transistor;
- a second transistor;
- a capacitor connected to a base of said first transistor and to a collector of said second transistor;
- a resistor connected to a contact point between said base of said first transistor and said capacitor and connected to said power source;
- an inductor for using said power source with a low supply voltage to generate a high negative pulse voltage on a contact point between said collector of said second transistor and said inductor connected to a power ground and said collector of said second transistor;
- an anode of said LED connected to said power source;
- a cathode of said LED connected to a contact point of said collector of said second transistor and said inductor;
- an emitter of said first transistor connected to said power ground;
- a collector of said first transistor connected to a base of said second transistor;
- a first end of said inductor connected to said collector of said second transistor, and a second end of said inductor connected to said power ground;
- and
- an emitter of said second transistor connected to said power source,
- wherein said negative pulse voltage formed on a contact point between said second transistor and said inductor has an absolute value higher than an activating voltage of said LED.
A circuit apparatus for driving a light emitting diode (LED) and being energized by a power source, comprising:
- an NPN transistor;
- a PNP transistor;
- a capacitor connected to a base of said NPN transistor and to a collector of said PNP transistor;
- a resistor connected to a contact point between said base of said NPN transistor and said capacitor and said power source;
- an inductor for using said power source with a low operating voltage to generate a high negative pulse voltage on a contact point between said collector of said PNP transistor and said inductor connected to a power ground and said collector of said PNP transistor;
- an anode of said LED connected to said power source;
- a cathode of said LED connected to a contact point of said collector of said PNP transistor and said inductor;
- an emitter of said NPN transistor connected to said power ground;
- a collector of said NPN transistor connected to a base of said PNP transistor;
- a first end of said inductor connected to said collector of said PNP transistor, and a second end of said inductor connected to said power ground;
- and
- an emitter of said PNP transistor connected to said power source,
- wherein said negative pulse voltage formed on a contact point between said PNP transistor and said inductor has an absolute value higher than an activating voltage of said LED.
Dependencies are inferred from the claim text.