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Subject: Re: Best way to power array of LEDs?
Date: Fri, 04 Oct 2002 06:50:09 GMT
NNTP-Posting-Date: Fri, 04 Oct 2002 02:50:09 EDT
Many LED stoplights are PWM operated, so it's operating at high instantaneous
power at low duty cycle. Next time you see bus stoplamps, shake your head while
you look at it, you'll see it's pulsed.
> Have assembled an array of LEDs for use as a 3rd brake light in my car,
> configured as 4 rows of 9 jumbo LEDs, as of yet unwired. Of course the power
> supply will be 12 volts nominal (13.8 volts, maximum).
> My options, as I see them, are:
> 1) Wire individual resistors to each LED based on its operating current
> 2) Wire each row in parallel and connect one resistor based on operating
> current for 9 LEDs
> 3) Install voltage regulator to output voltage (ie, 1.3 volts?) to operate
> all LEDs in parallel.
> What is the best method to power these from an intermittent (whenever I press
> the brake pedal) power source?
> Other options for powering this array?
> Note that my return address is corrupted in an attempt to reduce spam. If you
> choose to e-mail me, please correct my address as described below.
> Dave Carpenter
> Sound Logic
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