AN2042 Datasheet, PDF (1/30 Pages) STMicroelectronics – brightness LEDs with VIPer22A-E

AN2042
Application note
VIPower: dimmable driver for high
brightness LEDs with VIPer22A-E
Introduction
This application note introduces an innovative solution to drive high brightness 1W LEDs
(Light Emitting Diode), using VIPer22A-E in flyback configuration with output current control.
The power supply is able to drive an array of 1 to 8 LEDs in European range, i.e. 185-265
VAC with no modifications. By means of an input voltage doubler, it is possible to use the
same VIPer device also in U.S. input voltage range, guaranteeing the specs. A new control
technique is used to adjust the duty cycle of the output current, in order to dim the luminosity
of the LEDs down to 10% of the maximum value (patent pending by STMicroelectronics).
The proposed driver can be suitably used in applications such as landscape lighting, street
lighting, car parks, bollards, garden lighting, large area displays and so on.
Also domestic applications such as room lighting, decorative fixtures and architectural
lighting can benefit from the advantage of this dimmable light source.
10W Dimmable LEDs driver board layout
March 2007
Rev 4
1/30
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