# datasheet IR LED question

#### clangray

Joined Nov 4, 2018
227
Very basic power question for "Super Bright" Infrared LED datasheet. The continuous current listed in the data sheet is Ip = 100ma, Peak Forward Current = 1.0A. Forward voltage IF = 20ma is 1.2v, and IF = 100ma is 1.4v. Is it correct that I can go up to 100ma on the LED supply current? I know they are usually 20ma.

Thanks

#### ericgibbs

Joined Jan 29, 2010
16,790
Hi Clangray,
Yes, the 1A is pulse only.
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#### clangray

Joined Nov 4, 2018
227
Thx. What then is the forward current of this LED?

#### ronsimpson

Joined Oct 7, 2019
2,527
That is a very small LED.
20mA all the time.
100mA for 1% of the time. On time <=100uS
1A once. (very short time)

#### ericgibbs

Joined Jan 29, 2010
16,790
Hi c,
Sorry about the error, got my data lines crossed, it is OK at 100mA.
According to the d/s clip
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#### clangray

Joined Nov 4, 2018
227
Sorry about the error, got my data lines crossed, it is OK at 100mA.
So is OK at 100ma, all the time? If OK some of the time, what I should I set the current to all the time?

#### ronsimpson

Joined Oct 7, 2019
2,527
it is OK at 100mA
Only if it is on for 1% of the time.

20mA for all the time.

#### ericgibbs

Joined Jan 29, 2010
16,790
hi Ron,
The d/s states Continous for 100mA [ if it can be believed]
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#### ronsimpson

Joined Oct 7, 2019
2,527
I am wrong.
100mA 1.5V = 150mW. So at room temperature 100mA= max temperature inside the part.

#### Ya’akov

Joined Jan 27, 2019
6,856
I find that datasheet a bit confusing but it appears to be saying that you can use it continuously at 100mA if you are using an encoding scheme that requires no more than 100μs pulses with a duty cycle of no more than 1%. But, it also has the same specification for the maximum current of 1A. This is a contradiction so I suspect that it is an error.

It makes some sense that an LED intended for data transmission could be used at a higher current based on the average current due to the pulsing caused by digital encoding as opposed to continuous DC operation. It doesn’t make sense that both the 100mA and 1A specifications would have the same pulse length and duty cycle specification, that’s redundant.

#### ericgibbs

Joined Jan 29, 2010
16,790
hi,
The TS's original d/s is dated 2005, this d/s is dated 2010 with amendments to the spec.
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#### Ya’akov

Joined Jan 27, 2019
6,856
Yes, fixed…