| One of the biggest challenges to lighting
systems designers is how to optimize all the benefits of the latest
generation of LEDs. As LEDs generally
require an accurate and efficient DC current
source and a means for dimming, the LED
driver ICs must be designed to address these
requirements in a wide variety of applications.
Power solutions must be highly efficient,
robust, very compact
and cost effective.
In lieu of a high-voltage
AC power source
preferred by incandescent,
fluorescent, and
HPS bulbs, LEDs generally
use a much lower
DC voltage source typically
ranging from
only 8 to 72 V, depending
on the application
and the LED configuration.
However, most
new designs will operate
with inputs from 12
to 24 V DC, while some
retrofit designs will use
a 12 V AC input.
To ensure optimal performance and long
operating life, LEDs require an effective drive
circuit. These drive circuits must be capable
of operating from a loosely regulated power
rail, and also be both cost- and space-effective.
In order to maintain their long operating
life, it is imperative that an LED’s current
and temperature limits are not exceeded.
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This article was published in the Sept/Oct 2009 issue of LEDs Magazine.
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