Hello. I have a some questions about driving our epitex LEDs to achieve the largest energy delivered. I was wondering if you or someone else could tell me how I can drive the LEDs beyond the max forward current? The max forward current is 100mA for my LEDs, and the total output power is 48mW (e.g. for 3mm plastic LEDs I just ordered L810-33UP). I am attaching a PDF of the specification sheet of this LED. It says in the spec sheet that the max pulse current is 1000mA, and the duty cycle should be 1% for a pulse width of 10us. In our application we are turning the LEDs on for about 5ms so it is my understanding that the total energy delivered over this time would be 48mW*5ms=0.24 mili joules, when pulsing it would be 480mW*1% duty cycle*5mS=0.024 mJ. If my understanding is correct than it would make sense for me to stay at the max forward current of 100mA, and not pulse my LEDs to obtain the largest amount of energy.
I was wondering if I could pulse my LEDs in such a way that I could obtain more than the 0.24 mJ of energy over the 5ms? For example, could I pulse the LEDs at 1000mA for 5 ms as long as I waited 500 ms before I turned them on again, so the duty cycle would still be 1%? In this way I would have 480mW*5ms=2.4 mJ of energy delivered. I guess what I am wondering is if the 10us pulse width is the max, or I can increase it as long as the duty cycle doesn't go beyond 1%?
Currently I am using the Allegro 6277 LED drivers to drive my LEDs at 100mA, see link. (http://www.allegromicro.com/en/Products/Part_Numbers/6277/6277.pdf). Although I recently purchased different LED drivers that should be capable of driving the L810-33UP LEDs. The new LED drivers are made by ON Semiconductor NCP3065PG, see link. (http://www.onsemi.com/pub_link/Collateral/NCP3065.PDF). I was wondering if you could tell me how to wire this LED driver to ensure that the L810-33UP LEDs I purchased will deliver the maximum energy over 5ms and still not cause the LED to break?
Thank you in advance for your assistance, and the LED and driver spec sheets should be attached.
Kevin
I was wondering if I could pulse my LEDs in such a way that I could obtain more than the 0.24 mJ of energy over the 5ms? For example, could I pulse the LEDs at 1000mA for 5 ms as long as I waited 500 ms before I turned them on again, so the duty cycle would still be 1%? In this way I would have 480mW*5ms=2.4 mJ of energy delivered. I guess what I am wondering is if the 10us pulse width is the max, or I can increase it as long as the duty cycle doesn't go beyond 1%?
Currently I am using the Allegro 6277 LED drivers to drive my LEDs at 100mA, see link. (http://www.allegromicro.com/en/Products/Part_Numbers/6277/6277.pdf). Although I recently purchased different LED drivers that should be capable of driving the L810-33UP LEDs. The new LED drivers are made by ON Semiconductor NCP3065PG, see link. (http://www.onsemi.com/pub_link/Collateral/NCP3065.PDF). I was wondering if you could tell me how to wire this LED driver to ensure that the L810-33UP LEDs I purchased will deliver the maximum energy over 5ms and still not cause the LED to break?
Thank you in advance for your assistance, and the LED and driver spec sheets should be attached.
Kevin
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