Drive unit for a lighting element and operating method therefor

Patent metadata

Field	Value
Publication number	US-2016234902-A1
Application number	US-201415029722-A
Country	US
Kind code	A1
Filing date	Oct 14, 2014
Priority date	Oct 15, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

The invention relates to a drive unit for a lighting element and an operating method for such drive unit and to a lighting element including such drive unit. By selectively providing power to a control unit of the drive unit using different voltages at different stages of the overall drive unit, there is an additional degree of freedom which may be used for improving power efficiency, in particular for reducing standby power consumption, while still meeting specific space and cost constraints.

First claim

1 . A drive unit for a lighting element, the lighting element comprising at least one light source comprising at least one light emitting diode, the drive unit comprising:
a first power converter arranged for receiving input power by drawing at least a part of a predefined current waveshape and for outputting a bus voltage, a control unit arranged for controlling the drive unit, a second power converter for providing power to the control unit, the input of the second power converter ( 301 ) being coupled at least to the bus voltage, wherein the drive unit has, under the control of the control unit, an operation mode in which by means of the bus voltage an LED voltage is provided for operating the at least one light emitting diode and a standby mode in which the LED voltage for operating the at least one light emitting diode is not provided while power is provided to the control unit, wherein the control unit is arranged for adjusting a level of the bus voltage outputted by the first power converter from an operation level in the operation mode to a standby level in the standby mode and vice versa.

2 . The drive unit according to claim 1 , wherein the input of the second power converter is coupled to the first power converter via a switching circuitry, the switching circuitry also coupling the input of the second power converter to a further voltage provided within the drive unit.

3 . The drive unit according to claim 2 , wherein the switching circuitry is arranged for providing, to the second power converter, the bus voltage during the standby mode and the further voltage the during the operation mode.

4 . The lighting element according to claim 3 , further comprising a third power converter outputting the LED voltage for powering the at least one light emitting diode, the input of the third power converter being coupled at least to the bus voltage, wherein the further voltage is the LED voltage or another voltage provided by the third power converter.

5 . The drive unit according to claim 2 , wherein, during operation mode and standby mode, the switching circuitry is arranged such that the input of the second power converter is electrically connected to the further voltage when the bus voltage is above a predetermined threshold level and is electrically connected to the output of the first power converter when the bus voltage is below the predetermined threshold level.

6 . The drive unit according to claim 1 , wherein the first power converter is arranged for outputting, during the operation mode and/or the standby mode, the bus voltage being higher than the input voltage.

7 . The drive unit according to claim 6 , wherein the first power converter comprises a boost circuitry.

8 . The drive unit according to claim 1 , wherein the second power converter comprises a linear voltage regulator, preferably a low dropout regulator.

9 . The drive unit according to claim 1 , wherein drive unit is arranged for providing the LED voltage being lower than the bus voltage.

10 . The drive unit according to claim 4 , wherein the third power converter comprises a buck circuitry.

11 . The drive unit according to claim 1 , wherein the input voltage is 12 V of alternating current, wherein the first power converter includes a bridge rectifier.

12 . The drive unit according to claim 11 , wherein, at least during operation mode, the bus voltage is in the range of 20 to 28 V of direct current and the LED voltage is in the range of 8 to 16 V of direct current.

13 . The drive unit according to claim 1 , wherein the control unit is adapted to receive instructions and to control the lighting element in accordance to the instructions.

14 . A lighting element, in particular a multifaceted reflector light bulb having a diameter of approximately 51 mm, comprising:
at least one light source comprising at least one light emitting diode, and a drive unit according to claim 1 for driving the at least one light source.

15 . A method of operating a drive unit for a lighting element including at least one light emitting diode, such that the lighting element has an operation mode in which the at least one light emitting diode is operated by using a bus voltage and a standby mode in which the at least one light emitting diode is not operated while power is provided to a control unit, comprising the steps of:
receiving an input power by drawing at least a part of a predefined current waveshape, converting the input voltage and outputting the bus voltage, adjusting a level of the outputted bus voltage, upon switching between the operation mode and the standby mode, and, in standby mode, converting the bus voltage for providing power to the control unit.

Assignees

• Philips Lighting Holding Bv

Inventors

• Liu Junhu
• Radermacher Harald Josef Gunther
• Fu Jie
• Sun Xiao

Classifications

• H05B45/395

  Linear regulators · CPC title

• H05B33/0845 Primary

  Electricity · mapped topic

• H05B33/0815

  Electricity · mapped topic

• H05B33/0812

  Electricity · mapped topic

• H05B45/375

  using buck topology · CPC title