Led luminaire having high power led drive circuit

Abstract

A light emitting diode (LED) luminaire including a first light emitting group and a power factor correction unit connected to the first light emitting group, the power factor correction unit comprising at least one of a boost converter circuit, a buck converter circuit, and a buck-boost converter circuit. The at least one of the boost converter circuit, the buck converter circuit, and the buck-boost converter circuit are configured to step up or step down a first rectified voltage in response to a switching control signal from a control integrated circuit (IC) to generate a drive voltage equal to or greater than a first threshold voltage sufficient to drive the first light emitting group.

What is claimed is: 
     
         1 . A light emitting diode (LED) luminaire, comprising:
 a first light emitting group; and   a power factor correction unit connected to the first light emitting group, the power factor correction unit comprising at least one of a boost converter circuit, a buck converter circuit, and a buck-boost converter circuit,   wherein the at least one of the boost converter circuit, the buck converter circuit, and the buck-boost converter circuit are configured to step up or step down a first rectified voltage in response to a switching control signal from a control integrated circuit (IC) to generate a drive voltage equal to or greater than a first threshold voltage sufficient to drive the first light emitting group.   
     
     
         2 . The LED luminaire of  claim 1 , wherein the power factor correction unit comprises the boost converter circuit configured to step up a first rectified voltage in response to the switching control signal from the control integrated circuit (IC) to generate the drive voltage equal to or greater than the first threshold voltage sufficient to drive the first light emitting group. 
     
     
         3 . The LED luminaire of  claim 2 , wherein the boost converter circuit comprises:
 a first inductor configured to receive the first rectified voltage input from a rectifier of the LED luminaire, accumulate energy while a first switching device is turned on, and generate counter electromotive force while the first switching device is turned off; and   the first switching device connected in parallel to the first inductor is configured to be turned on and off in response to the switching control signal from the control IC.   
     
     
         4 . The LED luminaire of  claim 1 , wherein the power factor correction unit comprises the buck converter unit configured to step down the first rectified voltage in response to the switching control signal from a control integrated circuit (IC) to generate the drive voltage equal to or greater than the first threshold voltage sufficient to drive the first light emitting group. 
     
     
         5 . The LED luminaire of  claim 1 , wherein the power factor correction unit comprises the buck-boost converter circuit configured to step up or step down a first rectified voltage in response to the switching control signal from a control integrated circuit (IC) to generate the drive voltage equal to or greater than the first threshold voltage sufficient to drive the first light emitting group. 
     
     
         6 . The LED luminaire of  claim 2 , wherein:
 the boost converter circuit is configured to receive an AC voltage of 120 V; and   the drive voltage is generated to pulsate between the first threshold voltage and a maximum value of 260 V.   
     
     
         7 . The LED luminaire of  claim 4 , wherein:
 the buck converter circuit is configured to receive an AC voltage of 220 V; and   the drive voltage is generated to pulsate between the first threshold voltage and a maximum value of 220 V.   
     
     
         8 . The LED luminaire of  claim 5 , wherein:
 the buck-boost converter circuit is configured to receive an AC voltage of 90 V to 220 V; and   the drive voltage is generated to pulsate between the first threshold voltage and a maximum value of 260 V.   
     
     
         9 . The LED luminaire of  claim 3 , further comprising:
 a second light emitting group, each of the first and second light emitting groups comprising at least one LED, the first and second light emitting groups being sequentially driven by receiving the drive voltage from the power factor correction unit; and   an LED drive integrated circuit (IC) configured to determine a voltage level of the drive voltage and to control the sequential driving of the first and second light emitting groups according to the determined voltage level of the drive voltage,   wherein the rectifier of the LED luminaire to output the first rectified voltage generated by rectifying and then flattening an AC voltage.   
     
     
         10 . The LED luminaire of  claim 9 , wherein:
 the control integrated circuit (IC) is configured to output the switching control signal, the power factor correction unit comprising:   a DC voltage supply circuit configured to stabilize the first rectified voltage and to generate a DC power supplied to the control IC; and   an output voltage detection circuit connected to an output terminal of the boost converter circuit and configured to detect the drive voltage output from the boost converter circuit.   
     
     
         11 . The LED luminaire of  claim 10 , wherein the power factor correction unit further comprises:
 a zero point detection circuit configured to detect the energy stored in the first inductor, and   wherein the control IC is connected to the zero point detection circuit and the current detection circuit, and is configured to generate the switching control signal to turn on the first switching device when the energy stored in the first inductor reaches zero and to turn off the first switching device when the drive voltage becomes a preset critical value or less.   
     
     
         12 . The LED luminaire of  claim 1 , wherein:
 the at least one of the boost converter circuit, the buck converter circuit, and the buck-boost converter circuit is configured to step up or step down a first rectified voltage in response to a switching control signal from a control integrated circuit (IC) to generate a drive voltage equal to or greater than an n-th threshold voltage sufficient to drive the first though n-light light emitting groups, where n is a positive integer of 2 or more.