Patent ID: 8339070

Claim:
An LED lamp, comprising: a first LED string providing a first color temperature; a second LED string connected in parallel with the first LED string, the second LED string providing a second color temperature difference from the first color temperature; and a variable resistor interconnected between the first LED string and the second LED string, the variable resistor comprising a resistance track with resistance coils wound thereon and a slider moveable along the resistance track, one portion of resistance of the variable resistor connected in series with the first LED string, and the other portion of the resistance of the variable resistor connected in series with the second LED string; wherein when a position of the slider of the variable resistor is changed, a first electric current flowing through one of the first and second strings is increased, while a second electric current flowing through the other one of the first and second strings is decreased, such that the color temperature of the LED lamp is changed accordingly.