Life of a LED

Gargaman · February 17, 2016, 06:01:43 AM

Suppose that one wants to put a led indicator on a truebypass stompbox and decide to use a DPTD and the Millenium Bypass circuit.
How long this led will last? Will be the same as if it was engaged on a 3PDT wiring?
Will the led going to die before the other components in the Millenium circuit?
Will the kind of effect matter in these speculations?

Our Millenium:
LED - http://www.nteinc.com/specs/3000to3099/pdf/nte3019.pdf
Diode - 1N4148
Resistor 4k7
Transistor 2N7000

Let's the presume that this stompbox will be powered by an ideal 9v supply, without any surprising conditions.

Hatredman · February 17, 2016, 06:08:04 AM

The Millenium is a DC circuit. I don't see why it would matter. If you get the current right, a LED is a LED is a LED.

bluebunny · February 17, 2016, 07:42:23 AM

It will last forever, for relatively modest values of "forever". DPDT/M2 vs. 3PDT makes no difference. As Henry hinted, the LED doesn't know.

Kipper4 · February 17, 2016, 12:12:08 PM

LEDs are for life not just for Christmas.

armdnrdy · February 17, 2016, 02:02:16 PM

When I first saw the title of this thread....I thought that it was a new "tell all" book by one of the members of Zeppelin!

Gargaman · February 17, 2016, 02:24:10 PM

I confess that after posting I have an idea about a child tale of a LED.
But it would be tedious: now I'm on, now I'm off, on again...

The life of a transistor, maybe.

MrStab · February 17, 2016, 02:35:54 PM

i've used my Sony hi-fi nearly every day for 18 years, and the LEDs still work fine. i have older stuff which hasn't been used as frequently, and the LEDs still work in those.

just wish the rest of the f****** hi-fi worked properly. lol

R.G. · February 17, 2016, 02:41:40 PM

I'm curious about the question. Are you building man-rated space shot pedals or something?

Most electronic components have an expected life exceeding a human's, given that they are operated conservatively within their ratings. The exceptions are (1) electromechanical things like switches, pots, relays and similar; (2) electrolytic caps, which have a built-in decay mechanism; and (3) incandescent and vacuum-fluorescent lamps. If it moves, gets hot, or uses electrochemistry, it wears out.

Gargaman · February 17, 2016, 03:10:02 PM

Quote from: MrStab on February 17, 2016, 02:35:54 PM
i've used my Sony hi-fi nearly every day for 18 years, and the LEDs still work fine. i have older stuff which hasn't been used as frequently, and the LEDs still work in those.

just wish the rest of the f****** hi-fi worked properly. lol

Dinosaur leds..

Quote from: R.G. on February 17, 2016, 02:41:40 PM
I'm curious about the question. Are you building man-rated space shot pedals or something?

R.G., I can't understand completely because language barriers but I sense it's a joke, isn't it? Well, I'm building novice pedals for the last year or so, learning a lot here, making stupid questions too! Lately I start thinking about lifetime of the ones I have build. In Brazil 3PDT are very expensive, so I'm using DPDT wiht Millenium for pedals with LED. I thought that the circuit could interfere. I see now it's another stupid question!

R.G.,wasn't your signature "Expect there to be errors and defeat then?"
This has been my motto when buildind. Like a mantra. Thanks.
Best regards

"(1) electromechanical things like switches, pots, relays and similar;"
Cheap components teach this pretty fast!

bluebunny · February 17, 2016, 04:42:59 PM

Quote from: Guerrilha Music on February 17, 2016, 03:10:02 PM
R.G.,wasn't your signature "Expect there to be errors and defeat then?"

That was fellow Texan John Danna (jdansti) quoting R.G.

Jdansti · February 17, 2016, 05:19:47 PM

Howdy!

I agree with everyone else. Your DPDT will die before your LED.

Speaking of LED life (and off topic)... I'm slowly replacing the incandescent and CFL lamps in my house with LEDs. The price of LED lamps is falling, but they're still more expensive than halogen and CFLs (hard to get incandescents anymore in the US). The LEDs are supposed to last over 20 years, so here's the question. If my LED lamps in the house are less than 5 years old, would I be considered an asshole if I replaced them with cheaper lamps and took them with me when I sell the house?

(Sorry for the derailment, but I think the OP's question was answered.)

R.G. · February 17, 2016, 09:45:16 PM

In the words of the Scots "It's nae meanness, it's thrrrrift!"

Jdansti · February 17, 2016, 10:01:06 PM

That's the way I see it!

armdnrdy · February 17, 2016, 11:07:31 PM

Hey John...
After you gather up all of the lamps, make sure you collect the toilet paper and the fake log in the fireplace too!

Jdansti · February 17, 2016, 11:36:47 PM

And the door knobs!

Funny, when we bought the house, the previous owner said that part of the deal was that she would take some lilies from the front of the house because they were from her mother's funeral. She wanted to retrieve them after they moved out. We didn't have a problem with that. I came home from work one day and not only were the lilies gone, but she had dug up several rose bushes and took those too! We didn't bother confronting her about it.

MrStab · February 17, 2016, 11:39:46 PM

Quote from: Jdansti on February 17, 2016, 05:19:47 PM
Howdy!
Speaking of LED life (and off topic)... I'm slowly replacing the incandescent and CFL lamps in my house with LEDs.

also off-topic, but my house has been half-LED for a coupla years now and they're insanely bright for a fraction of the running cost. i notice things in pedals which not even the flourescent strip in my garage picks up. a few have failed quite early, but that could be down to no prior research on brands. i highly-recommend it in any case.

Quote from: R.G. on February 17, 2016, 09:45:16 PM
In the words of the Scots "It's nae meanness, it's thrrrrift!"

that's not true. it's entirely meanness.

Quackzed · February 17, 2016, 11:58:34 PM

QuoteIf it moves, gets hot, or uses electrochemistry, it wears out.

Why R.G. Why!?!?!?!?!?!?!?!?!?

Jdansti · February 18, 2016, 02:49:57 AM

^My guess is entropy. Things that move break down due to friction, things that get relatively hot change composition over time, and materials in electrochemical processes are converted to chemicals that don't support the process. You know, like dilithium crystals and gaviscon tubes.

bluebunny · February 18, 2016, 03:03:35 AM

Gargaman · February 18, 2016, 12:28:51 PM

Nice to meet you, John!
Don't lose your cat under the mess..
I pretty much agree with derailments, so feel free to ignore or bypass some very basics questions that I have about the datasheet.
I mean, in our LED datasheet the test conditions says a 20mA current. We presume a 4k5 limiting resistor, for a 9v supply, right?
If it has a 1A Peak Forward Current, does it means that the LED blows if we exceed 1A (wich means a minimum resistance of 9R)?
Is there a minimal current for the LED to start emitting light, and does the light intensity varies along the current range that it can handle?
Doesn't the LED gets hot when it blows?

I think someone's gonna impose me some hours on the breadboard with my LED friend...

News:

Life of a LED