I am working on an IR based distance sensor that operates with modulated light (40kHz).
I’d now like to do some tests with the emitter on whether a low current with a larger duty cycle produces best results or if a high current with low duty cycle will improve the sensor.
The LED I am working with states a max pulsed current of 1.2A for 100ns as max value.
I am now looking for a logic level MOSFET that will allow me to perform this test.
Having never worked before with transistors/mosfets, I am now a bit overwhelmed by the amount of models available.
My basic requirements would be:
- logic level gate
- 1A at 5-12V for the LED
- fast switching time (< 1uS, if possible down to 100ns but not absolutely necessary since I am not even sure yet if the Atmega allows for such small duty cycles on a 40kHz frequency)
Can someone who has some experience in this recommend a part for this application?
Is there anything else important to consider? I read about possible overheating problems with such high frequencys for example?!
Thank you very much for your advice, it is much appreciated!
Have a great day!