At 08:25 PM 9/5/2012, you wrote:
>I have a pin coming out of a chip that indicates an error condition. Pin
>will be at +5 or ground. (e.g. not a 3.3 volt system)
>
>The output requires at least 4.7K ohms resistance, or risk pulling more th=
an
>the iMAX rated current for that pin.
>
>PCB already done, no room for a transistor to amplify the output (next
>revision).
>
>So the question is this: What LED would you use to get the most noticeable
>indication from 5 volts through a 4K7?
>
>I'm thinking very small, but diffuse red.
>
>But then I notice the ones with the highest mcd rating are always clear...
>
>Any experienced advice?

I think it depends a lot on the package. With a Vf of 2.1V, you could
get maybe half a mA, which should be sufficient for normal room lighting.

Tinted will give you more contrast. Tinted clear gives more brightness
viewed head-on (assuming a lens at the end) but diffused give a lot more
viewing angle.

In 3mm types- SSL-LX3052ID is



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>1-970-462-7764
>
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