Back to results
US 8,410,711 B2Granted
Circuits and methods for driving light sources
AssigneeO2Micro, Inc.
InventorsYung Lin Lin, Sterling Du
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeO2Micro, Inc.
InventorsYung Lin Lin, Sterling Du
Estimating the term…
In one embodiment, a driving circuit includes an AC/DC converter which converts an AC voltage to a DC voltage and a DC/DC linear regulator which regulates a current through, e.g., an LED light source, according to a first current reference if a monitoring signal indicating the DC voltage is within a predetermined range, and regulates the current according to a second current reference less than the first current reference if the monitoring signal is beyond the predetermined range. In another embodiment, a controller controlling power to an LED light source turns on a first plurality of LEDs and turns off a second plurality of LEDs if a monitoring signal indicative of a DC voltage received by the LED light source is within a predetermined range, and turns on both first and second plurality of LEDs if the monitoring signal is beyond the predetermined range.
A controller for controlling power to a light-emitting diode (LED) light source which receives a DC voltage, wherein said LED light source comprises a first plurality of LEDs and a second plurality of LEDs, and wherein said controller is operable for turning on said first plurality of LEDs and turning off said second plurality of LEDs if a signal indicative of said DC voltage is within a predetermined range, and for turning on both said first plurality and said second plurality of LEDs if said signal indicative of said DC voltage is beyond said predetermined range, said controller comprising:
A controller for controlling power to a light-emitting diode (LED) light source which receives a DC voltage, wherein said LED light source comprises a first plurality of LEDs and a second plurality of LEDs, and wherein said controller is operable for turning on said first plurality of LEDs and turning off said second plurality of LEDs if a signal indicative of said DC voltage is within a predetermined range, and for turning on both said first plurality and said second plurality of LEDs if said signal indicative of said DC voltage is beyond said predetermined range, said controller comprising:
A controller for controlling power to a light-emitting diode (LED) light source which receives a DC voltage, wherein said LED light source comprises a first plurality of LEDs and a second plurality of LEDs, and wherein said controller is operable for turning on said first plurality of LEDs and turning off said second plurality of LEDs if a signal indicative of said DC voltage is within a predetermined range, and for turning on both said first plurality and said second plurality of LEDs if said signal indicative of said DC voltage is beyond said predetermined range, said controller comprising:
Dependencies are inferred from the claim text.