Date: Tue, 18 Sep 2007 15:34:39 -0600
Reply-To: vanagonvw <ac.vanagon@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: vanagonvw <ac.vanagon@GMAIL.COM>
Subject: Re: LVC adding LED interior lighting
In-Reply-To: <20070918211320.53ADD1165C3@hamburg.alientech.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Gonna point out that this is getting a bit mean spirited. Is it ego
that makes folks behave like this, as if only one person knows how to do
something that can be done a dozen different ways? Those who do things
like this for a living, are well aware of how this can properly be done.
Those who read electronics digest on the weekends, usually know just
enough to screw things up. Those who don't know, are asking for help,
not lectures, not bullshit, not "so what if they blow up"
Just offer some help, and hope for the karma to come back to you one day
when you need it.
If the spec sheet for the diode calls for a 5V power source, use a 5V
power source. I suggest that the OP do a quick search on how to wire up
LEDs, where he will find answers, and a whole lot less testosterone.
>
>> That's false.
>
> It's correct. You just don't know what you're talking about.
>
>> By connecting LEDs in serial you force them to all operate at
>> a same current but different voltages. This would be a false design if
>> all LEDs are different. One LED may be required to operate at 15MA but
>> another may be 300MA.
>
> Oops. You either contradicted yourself or are displaying extreme
> ignorance.
>
>
>> If LEDs connected in serial
>
> It's "series."
>
>> are same LEDs, by connecting them in serial
>
> It's "series."
>
>> you allow them to operate at a same current, which is fine, but still
>> each one is forced to operate at a different power level unless every
>> single LED is identical.
>
> So? It's not a problem unless you exceed their maximum rating. If you
> keep the current to 20 mA, you won't do that (for the _vast_ majority
> of LEDs).
>
>> In reality if the LEDs are not produced from
>> a same silicon wafer
>
> Of course they aren't. Most LEDs are made from gallium arsenide. Blue
> ones are typically made from indium gallium nitride. I'm not aware of
> any which are based on a silicon chemistry (although silicon carbide is
> sometimes used as a substrate, due to it's thermal conductivity).
>
>> If somehow one of the LED is shorted out, because of vibration of your
>> westy, or just a simple internal failure that usually happens to
>> diodes
>> as a short first, your other LED will be instantly destroyed too.
>
> LEDs have lifetimes in the 10,000-100,000 range. They cost less than a
> buck. So what?
>
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