UCC28810 100W单级PFC LED恒流驱动电源.pdf

Using the UCC28810EVM-002 Users Guide Literature Number: SLUU355A March 2009 – Revised June 2009 Users Guide SLUU355A – March 2009 – Revised June 2009 A 0.9-A Constant Current Supply with PFC for 100-W LED Lighting Applications 1 Introduction The UCC28810EVM-002 is a constant current non-isolated power supply for LED lighting applications. It will convert universal mains (90 VRMS to 264 VRMS) to a 0.9-A constant current into a 100-W load. This evaluation module will allow the customer evaluate the UCC28810/11 in a typical LED lighting application. 2 Description The evaluation module uses a two stage approach to controlling the output current. The first stage is a transition mode PFC circuit. This ensures the design meets the harmonic current or power factor requirements set out by various standards, such as EN61000-3-2. The PFC circuit converts the AC input to a regulated DC voltage. This DC voltage can be configured in one of two ways. The default configuration of the module is that of a boost follower type PFC. The boost follower PFC is where the PFC regulated output DC voltage tracks the AC input peak voltage. The second configuration requires removing some components and changing a resistor value see below for more details. This second configuration removes the tracking element of the PFC circuit. The PFC DC output voltage will then be regulated to a fixed value in the region of 396 VDC. The second stage also uses transition mode but is configured as a buck converter. It converts the