Cecil Moore wrote:
Wes Stewart wrote:

On 5 Jan 2005 17:07:51 -0800, "Cecil Moore" wrote:
|Slightly off topic - I've seen a couple of new automobiles with
|time-multiplexed LED taillights. What would be the advantage of such a
|design in an automobile?

What the hell is "time-multiplexed"?


In this case, on half the time and off half the time at about
a 100 Hz rate. Maybe square-wave power? Maybe pulse-width
modulation, different from night to day? I thought it was a
simple question to which someone had a simple answer.

"Time-multiplexed" means that they're turned on in sequence, without all
being on at once. That would be as opposed to simply pulse modulated all
at once.

My guess is that they're pulse modulated to provide easy and efficient
control of the brightness, and possibly compensation for voltage and/or
temperature. If they're time-multiplexed as well, that would even out
the total current drain rather than its being in the form of big current
pulses.

Are they really time-multiplexed, or are they all pulsed at once?

Roy Lewallen, W7EL