What is T in tp/T, for LED diode?

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insight

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I found this parameter tp/T for LED diode and I do not know what is T for?

tp is Pulse Duration (ms), tp/T is just a number, from 0.0 to 1.0. It seems as pulse duration compared to something, but what is something?

Any ideas?
 
I found this parameter tp/T for LED diode and I do not know what is T for?

tp is Pulse Duration (ms), tp/T is just a number, from 0.0 to 1.0. It seems as pulse duration compared to something, but what is something?

Any ideas?

hi,
Look at this image.
 

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Ok, so it is not just for one shot, but it is a STANDARD continuous stream of pulses. That is important.

Practically if tp/T= 0.25, that means that tp= 0.25 x T = 0.25 x 10ms = 2.5ms or pulse lasting 2.5ms is emitted every 10ms.

Even taken further, for the case in question, it shows how much current can go through LED, without destroying it, at a different pulse lengths.
 
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hi,
I am not sure that you should extrapolate the specification in that way.???
Its only a 'd/s note' on how it performed being pulsed ON for 100uS at 10mS intervals.

Look at this opto graph.
 

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This is the troublemaker:

**broken link removed**

So I am talking in a context of the above diagram.
 
hi,
Thats a helpful graph, for that LED it holds true up to tp/T.
I would if you keep the current, ON time and repetition rate within limits shown, you should have no problems.

What are you planning for the ON time and rate,to run the LED.?
 
ericgibbs,

While I have your attention: do you know how to turn on a laser diode and light sensor in 0.5ns, keep them on for 3.0ns and turn it off in another 0.5ns? I've been dreaming (literally) about making a laser rangefinder, accurate to 1m, and I need something like that.
 
I am working on several 'big' ideas, but I kind off work a little bit on the second one, than on the third, than on the first. If you know what I mean. I buy electronic components like kids buys sweets. I was just trying to understand spec sheet for this one, when I got stuck on T in tp/T.

If you want the BIG idea, I was 8 years old when Americans landed on the Moon. So I am working on a Eagle, the Moon lander, only mine is going to be made of Polystyrene . Currently project is at a stage of Lunar Lander Research Vehicle, made of coat-hangers
 
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