摘要:
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.
摘要:
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.
摘要:
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).
摘要翻译:具有远程电容器放置的电子镇流器包括第一壳体(34); 第二壳体(36); AC / DC转换器(22); 可操作地连接到AC / DC转换器(22)的DC总线(24); 可操作地连接到DC总线(24)的灯驱动器(26); 以及与电容器线(30)连接到DC总线(24)的存储电容器(32)。 AC / DC转换器(22),DC总线(24)和灯驱动器(26)设置在第一壳体(34)中; 存储电容器(32)设置在第二壳体(36)中; 并且所述第一壳体(34)被热隔离并与所述第二壳体(36)物理分离。
摘要:
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.
摘要:
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.
摘要:
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).
摘要:
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).
摘要:
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.
摘要:
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.
摘要:
The driver circuit for light emitting diodes (LEDs) of the present invention provides power to LEDs using pulse width modulation (PWM). The driver circuit 100 uses current feedback to adjust power to LED arrays 54 and provides a full light and a dim mode.