Patent ID: 7839095

Claim:
A lamp comprising: a light emitting element; a lamp terminal adapted for connecting to a line voltage; and a lamp voltage conversion circuit within the lamp and connected in series between the light emitting element and the lamp terminal, the voltage conversion circuit including a phase-controlled dimming circuit having a triac and a voltage controlled resistor connected to said triac, the voltage controller resistor having a resistance that varies in response to variation of the line voltage at the lamp terminal, wherein variation of the line voltage occurs when the root mean square (RMS) magnitude of the line voltage over a first period of time differs from the RMS magnitude of the line voltage over a second period of time, such that the variation of the resistance of the voltage controlled resistor in response to the variation in line voltage results in the phase-controlled dimming circuit providing, to the light emitting element, a time-varying voltage having a substantially constant magnitude.