Cree Gmbh

Matthew K Murphy

Kurt S Wilcox

Pierre Deschenes

Craig D Raleigh

Bernd Clauberg

A driver is connectable to an external power supply and configured to output a variable driving current for one or more loads, such as LEDs. A low intensity dimming module is operable to divert some or all of the driving current away from the LEDs when a user selects a very low level of light intensity so that the driver has a constant minimum load. The low intensity dimming module prevents performance issues that commonly affect drivers under light load conditions.

Low intensity dimming circuit for an LED lamp and method of controlling an LED

A thermal protection device includes a heating circuit that develops a first heat magnitude when exposed to a temperature below a threshold and further develops a second heat magnitude greater than the first heat magnitude when exposed to a temperature above the threshold. A thermal circuit breaker is disposed in heat communication with the heating circuit and has component having a holding temperature greater than the threshold and a trip temperature greater than the holding temperature.

Thermal protection device

A lamp driver responsive to a control signal that is variable in a predetermined control range includes a circuit operable in response to a value of the control signal within the predetermined control range to develop a first current and a lamp control voltage dependent upon the value of the control signal. A shutdown interface is operable in response to a value of the control signal outside of the predetermined control range to develop a second current to turn off a lamp.

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Mukwonago, WI, United States of America

Matthew K Murphy