Moog Music Forum

Ok, maybe this is a really stupid question, but...

I tend to leave my LP on a lot, like four or five hours a day. Do the instrument display LEDs have a limited life span, like four or five years? Do they burn out like a regular light bulb, or do they just dim a little bit?

Blue LED's have a short lifespan. I dunno why. Other colors last quite a while...80,000-100,000 hours or more. Sometimes dying LED's flicker and sometimes they dim, or they just go out suddenly, so it's hard to say what they will do.

Typically, blue LEDs are run fairly bright with a smaller resistor.

Just going by the estimates stated above... it's at least 10 year lifespan of being on constantly without ever being turned off.

Franz Schiller wrote:Ok, maybe this is a really stupid question, but...

I tend to leave my LP on a lot, like four or five hours a day. Do the instrument display LEDs have a limited life span, like four or five years? Do they burn out like a regular light bulb, or do they just dim a little bit?

For what it's worth, my MS-20's LEDs were going strong when I owned one in 2005. That's probably a good 25 years or so.

You need more voltage to push into higher wavelength LEDs, this may have something to do with Blue ones dying a little sooner. Red is most common (on ms-20 for instance) and is of course low on the spectrum.

Excellent. Ten years sounds great to me. Thanks guys, I feel way better now.

Could anyone confirm if your preset and octave LEDs are dimmer when red than the glide sync and output red led's? Thanks!

Franz Schiller wrote:Ok, maybe this is a really stupid question, but...

I tend to leave my LP on a lot, like four or five hours a day. Do the instrument display LEDs have a limited life span, like four or five years? Do they burn out like a regular light bulb, or do they just dim a little bit?

Not a stupid question at all !

All LEDs have a limited lifespan, which is usually much longer than regular light bulbs. It depends on how they're powered. Many engineers will prolong their life by powering them in pulses, fast enough so the human eye will see them continually on, effectively doubling their rated continuously lit MTBF. But not all devices power them this way.

Some LEDs have a shorter lifespan than others, especially blue ones because of the materials used in their construction in order to produce blue light. All LEDs will slowly loose brightness, until they'll no longer light up. They normally don't go out all of a sudden like regular light bulbs, although it has been known to happen especially with very old ones made in the 70's.

But generally, they have a very, very long lifespan if powered properly. I have a 27 years old LED clock, which has been powered on since 1985, still going strong on all seven segments numbers, since they are "strobed" as described earlier. It might be a little dimmer than when I first bought it, but still bright enough the read even in daylight.

As with any other things, they are of different quality. I remember an old LED calculator from 1981 (Texas Instruments TI-30) of which many of the segments of its display had failed after only about a year of occasional use in high school, outside the warranty of course...

But I also have a 1981 Korg Mono/Poly synth on which all the LEDs are still going strong, and they're not even strobed ! Oh, and a 1972 Roland TR-77 of which the tempo red LED is still working fine, although it's only flashing.

The moral is; the less time a LED is on, or the lower the power is applied to it, the longer it should last. Although the MTBF of a quality red LED is typically around 100 000 hours. Divide that by 3 for blue ones.

My take on it.