From: Tilmann Reh
Subject: Re: Best way to power array of LEDs?
Date: Fri, 04 Oct 2002 08:19:10 +0200
Organization: Autometer GmbH
NNTP-Posting-Date: 4 Oct 2002 06:17:27 GMT
X-Mailer: Mozilla 4.78 [de] (Win98; U)
> 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 =
> 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 operatin=
> current for 9 LEDs
> 3) Install voltage regulator to output voltage (ie, 1.3 volts?) to oper=
> all LEDs in parallel.
> What is the best method to power these from an intermittent (whenever I=
> the brake pedal) power source?
Better use many LEDs in series to avoid unnecessary power loss.
With 12V supply, you can use about 5 LEDs in series and a smaller
resistor for each chain. These chains are then connected in parallel.
Dipl.-Ing. Tilmann Reh
Autometer GmbH Siegen - Elektronik nach Ma=DF.
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