Patent ID: 8680775

Claim:
A lighting driver circuit operable to provide power to a light source from a power source, said lighting driver circuit comprising: an isolating flyback circuit coupled between the power source and the light source, the isolating flyback circuit comprising a transformer having a primary winding and a secondary winding; a switching element connected to the primary winding of the transformer and operable to draw current through the primary winding of the transformer from the power source when turned ON as a function of a pulse width modulation signal; a diode connected to the secondary winding of the transformer and effective to provide power from the secondary winding of the transformer to the light source; and a capacitor connected to the diode effective to smooth the output of the diode; and a control circuit operable to provide the pulse width modulation signal to the switching element as a function of a control signal and a feedback signal, said control circuit comprising a reference signal generator operable to receive the control signal and provide a reference potential corresponding to a frequency of the control signal; an operational amplifier operable to receive the feedback signal and the reference potential and provide a reference voltage representative of a difference between the received feedback signal and the reference potential; a driver circuit operable to receive the reference voltage and provide the pulse width modulation signal as a function of the received reference voltage and a stop threshold voltage, wherein the driver circuit turns the switching element OFF as a function of a comparison of the reference voltage to the stop threshold voltage.