Patent ID: 8441199

Claim:
A circuit for controlling a set of light emitting diode strings, comprising: a programmable controller having one or more associated detectors, the programmable controller obtains data related to one or more measurable parameters for the set of light emitting diode strings via the associated detectors, determines a drive value based at least in part on the measurable parameters, and generates a control signal based on the drive value; a power supply system, having power factor correction capability, obtains the control signal as a first input, and an ac waveform voltage as a second input, and generates a drive voltage based at least in part on at least one of the control signal or the ac waveform voltage; and a programmable variable resistor included in the power supply for setting a set of operating conditions for an input current and voltage control loop that facilitate the power supply in generating the drive voltage; wherein the one or more associated detectors includes at least a first triode region detector coupled to at least a first light emitting diode in the set of light emitting diode strings, the first triode region detector determines a limit triode region for the first light emitting diode; and wherein the programmable controller determines the drive value based at least in part on the limit triode region.