Re: 12 LED resistance circuit help

On Sat, 23 Apr 2005 05:13:57 GMT, "Anthony Fremont"
<spam@xxxxxxxxxxxx> wrote:

>
>"John Bokma" wrote:
>
><snipped exactly what I was going to post>
>
>> Note that I did this calculation, later checked it with a voltage
>meter,
>> and yet already 2 exotic LEDs died on me. I think it's a bad badge.
>> (Unless someone can point out my errors).
>
>I came up with the same calculation as you. If LEDs are dieing, then
>20mA may be a bit too much current. Since there are two LEDs in series,
>one may hog more current than the other resulting in its demise.

---
So, you're saying that because the LEDs may not be identical one may
be drawing more current than the other?
---

>You
>might consider not driving them so hard. There is probably a relatively
>insignificant brightness difference between 10mA and 20mA anyway.

--
John Fields
Professional Circuit Designer
.

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