Abstract: Circuits useful in achieving efficient current control of LEDs based on a dimming control input are described. The circuits use a combination of PWM dimming and analog dimming to achieve a highly efficient LED driver over a wide range of dimming from near 0% to 100% light output.

Abstract: 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.

Abstract: An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (Ploss) exceeds an LED lamp electronics power loss limit (Plim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

Abstract: An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

Abstract: Circuits useful in achieving efficient current control of LEDs based on a dimming control input are described. The circuits use a combination of PWM dimming and analog dimming to achieve a highly efficient LED driver over a wide range of dimming from near 0% to 100% light output.

Abstract: An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

Abstract: An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (Ploss) exceeds an LED lamp electronics power loss limit (Plim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

Abstract: A lighting fixture (20-23) mechanically encloses a LED module (30), which includes at least one LED (40) and can further include a LED driver (50) in electrical communication with the LED(s) (40) to operably provide a LED drive signal to the at least one LED (40), a thermal management system (60) in thermal communication with the LED(s) (40) and the lighting fixture (20-23) to facilitate a heat transfer from the LED(s) (40) to the lighting fixture (20-23), and/or a beam shaper (70) in optical communication with the LED(s) (40) to modify an illumination profile of a radiation beam emitted by the LED(s) (40).

Abstract: An electronic ballast with remote capacitor placement includes a first housing (34); a second housing (36); an AC/DC converter (22); a DC bus (24) operably connected to the AC/DC converter (22); a lamp driver (26) operably connected to the DC bus (24); and a storage capacitor (32) connected to the DC bus (24) with capacitor wires (30). The AC/DC converter (22), the DC bus (24), and the lamp driver (26) are disposed in the first housing (34); the storage capacitor (32) is disposed in the second housing (36); and the first housing (34) is thermally isolated and physically separated from the second housing (36).

Abstract: A LED based lighting system (20) employs a LED load temperature sensor (40) for generating a temperature-sensing signal (TSS) indicative of an operational temperature of the LED load (10), a LED current sensor (50) for generating a current-sensing signal (CSS) indicative of a flow of the LED current (ILED) through the LED load (10), and a LED driver (30) for regulating the flow of the LED current (ILED) through the LED load (10) as a function a mixture of the current-sensing signal (CSS) and the temperature-sensing signal (TSS). The system (20) can further employ a driver disable notifier (80) and a LED driver disabler (90), or alternatively, a fuse network (100) for disabling the LED driver (30) upon a detection of a fault condition of the system (20).

Abstract: A LED package employs a heatsink (30), a LED (10) thermally mounted to the heatsink (30), and a printed circuit board (20) including a hole (21) extending there through for facilitating the thermal surface mounting of the LED (10) onto the heatsink (30). The printed circuit board (20) is preferably surface mounted onto the heatsink (30). The LED (10) is seated within the hole (21) and includes leads (11, 12) electrically coupled to the printed circuit board (10) wherein a portion of each lead (11, 12) is partially seated within the hole (21), and/or the heatsink (30) includes a post (31) seated within the hole (21) and the LED is thermally mounted to the post (31).

Abstract: A lighting fixture (20-23) mechanically encloses a LED module (30), which includes at least one LED (40) and can further include a LED driver (50) in electrical communication with the LED(s) (40) to operably provide a LED drive signal to the at least one LED (40), a thermal management system (60) in thermal communication with the LED(s) (40) and the lighting fixture (20-23) to facilitate a heat transfer from the LED(s) (40) to the lighting fixture (20-23), and/or a beam shaper (70) in optical communication with the LED(s) (40) to modify an illumination profile of a radiation beam emitted by the LED(s) (40).

Abstract: An electronic ballast with remote capacitor placement includes a first housing (34); a second housing (36); an AC/DC converter (22); a DC bus (24) operably connected to the AC/DC converter (22); a lamp driver (26) operably connected to the DC bus (24); and a storage capacitor (32) connected to the DC bus (24) with capacitor wires (30). The AC/DC converter (22), the DC bus (24), and the lamp driver (26) are disposed in the first housing (34); the storage capacitor (32) is disposed in the second housing (36); and the first housing (34) is thermally isolated and physically separated from the second housing (36).

Abstract: The power supply (20) for LEDs provides power to a LED light source (10) having a variable number of LEDs wired in series and/or in parallel. The power supply (20) uses current and voltage feedback to adjust power to the LEDs and provides protection to the LED light source (10). A feedback controller (27) compares sensed current and sensed voltage to a reference signal and generates a feedback signal, which is processed by a power factor corrector (124) to adjust the current flow through the transformer supplying current to the LEDs. A LED control switch (24) clamps a peak of the current to the LEDs to provide further protection to the LED light source (10). A short/open detection circuit (30) indicates any detection of a “LED outage” of the LED light source (10).

Abstract: A LED based lighting system (20) employs a LED load temperature sensor (40) for generating a temperature-sensing signal (TSS) indicative of an operational temperature of the LED load (10), a LED current sensor (50) for generating a current-sensing signal (CSS) indicative of a flow of the LED current (ILED) through the LED load (10), and a LED driver (30) for regulating the flow of the LED current (ILED) through the LED load (10) as a function a mixture of the current-sensing signal (CSS) and the temperature-sensing signal (TSS). The system (20) can further employ a driver disable notifier (80) and a LED driver disabler (90), or alternatively, a fuse network (100) for disabling the LED driver (30) upon a detection of a fault condition of the system (20).

Abstract: One form of a traffic light (10, 11) employs one or more LED circuits connected to a voltage source (VS). Each LED circuit includes a series connection of a LED array (30), a current limiter (31) and an electronic switch (32). Each current limiter (31) controls a flow of LED current (IRL) through an associated LED array (30) whenever a switch controller (21) closes the associated electronic switch (32). Another form of a traffic light (60, 61) employs one or more LED circuits connected to a current source (IS). Each LED circuit includes a parallel connection of a LED array (80) and an electronic switch (81). A LED current (IRL) flows through an LED array (80) whenever a switch controller (71) opens the associated electronic switch (81).

Abstract: The power supply (20) for LEDs provides power to a LED light source (10) having a variable number of LEDs wired in series and/or in parallel. The power supply (20) uses current and voltage feedback to adjust power to the LEDs and provides protection to the LED light source (10). A feedback controller (27) compares sensed current and sensed voltage to a reference signal and generates a feedback signal, which is processed by a power factor corrector (124) to adjust the current flow through the transformer supplying current to the LEDs. A LED control switch (24) clamps a peak of the current to the LEDs to provide further protection to the LED light source (10). A short/open detection circuit (30) indicates any detection of a “LED outage” of the LED light source (10).

Abstract: A LED driver includes a high frequency inverter and an impedance circuit. The high frequency inverter operates to produce a high frequency voltage source whereby the impedance circuit directs a flow of alternating current through a LED array including one or more anti-parallel LED pairs, one or more anti-parallel LED strings, and/or one or more anti-parallel LED matrixes. A transistor can be employed to divert the flow of the alternating current from the LED array, or to vary the flow of the alternating current through LED array.

Abstract: An apparatus for controlling overshoots in the switching of LED arrays in a system having a switching voltage converter providing the biasing voltage for the LED array. By synchronizing a switching converter to an LED turn-on signal, loading on the voltage converter can be controlled such that output conduction of the converter only occurs when LEDs that are to be displayed are switched on to provide loading to the output of the converter. A Sample and hold method is employed to effectively store the current information in a previous “on” interval and use it for the current control in a following interval with inhibited current overshoot.

Abstract: A LED driver is disclosed. The LED driver includes a high frequency inverter and an impedance circuit. The high frequency inverter operates to produce a high frequency voltage source whereby the impedance circuit directs a flow of alternating current through a LED array including one or more anti-parallel LED pairs, one or more anti-parallel LED strings, and/or one or more anti-parallel LED matrixes. A transistor can be employed to divert the flow of the alternating current from the LED array, or to vary the flow of the alternating current through LED array.