Specifications

Lighting
LED lighting
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LED lighting
The expanding role for
LED lighting
Light-emitting diodes (LEDs) are a
rapidly evolving technology and
are becoming viable for many
general lighting applications, usually
referred to as solid-state lighting.
The most relevant examples of LED
lighting applications are indoor
uses in commercial, industrial, and
residential environments; outdoor
applications like street lights and
parking lights; and architectural and
decorative lighting where LEDs were
initially adopted because of their
ability to emit the whole spectrum
of colors.
LEDs have been an effective solution
for architectural lighting for some
time. Today LEDs are penetrating
the mainstream general lighting
market, thanks to their higher
performance compared to other
lighting technologies:
• They have a much longer
lifetime than other lighting
technologies. LEDs can operate
for 50,000 hours versus 1,000
to 2,000 hours for incandescent
lamps and about 5,000 to 10,000
hours for compact fluorescent
lights (CFLs). This markedly longer
lifetime makes LEDs ideal for many
commercial and industrial lighting
applications where the labor cost
to replace a lamp is high.
• Their energy efficiency is
superior to incandescent and
halogen lamps, and often
equivalent to fluorescent lamps.
Additionally, the efficacy of LEDs
is continuously improving; the
efficacy of white LEDs (WLEDs)
is now forecasted to improve by
about 50% over the next three to
four years.
• They have a small form factor.
LEDs fit in some form factors like
MR16 and GU10 lamps where CFLs
do not.
• They can be dimmed with the
appropriate driver. Fluorescent
lamps pose technical limitations
when the application requires
dimming. Although conventional
LED designs have encountered
similar issues, innovative LED
drivers from Maxim are compat-
ible with triac and trailing-edge
dimmers.
• They emit a very directional
light. Unlike other lighting technol-
ogies, LEDs are more appropriate
for applications like narrow-angle
reflector lamps that require a very
directional light.
• Their efficacy improves at lower
temperatures. The efficacy of
fluorescent lamps degrades at
lower temperatures. In contrast,
LEDs are ideal for applications with
a low ambient temperature like
refrigerator lighting.
• It is very easy to change the
color of their emitted light. This
makes RGB LEDs ideal for applica-
tions like architectural and mood
lighting where the color of the
light must change in real time.
In summary, LEDs offer many advan-
tages over incandescent lamps and
fluorescent lamps. Consequently,
designers continue to find more
applications for LED lighting, but
that discussion could consume us
for a long while. This review will
focus on only two, but quite timely,
applications: LED retrofit lamps and
remote-controlled LED lighting.
LED retrofit lamps are made to
replace incandescent, halogen, or
fluorescent lamps in the same socket.
These LED lamps must fit in the
existing form factor and be compat-
ible with the existing infrastructure.
LEDs for remote-controlled lighting
allow greater flexibility in dimming
and changing the color of the light.
Moreover, the use of wireless or
powerline-communication (PLC)
remote controls facilitates even
more new LED applications.
LED retrofit lamps
Many would argue that the LED
retrofit lamp market is the fastest
growing application for LED lighting
today. The reason for this fast growth
is actually quite straightforward:
these lamps do not require a new
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PAR20
LuxDot™