There's no point in using a tight tolerance high stability resistor when the LED has very wide tolerance and a poor stability.
Where did you read that my particular LED has very bad stability over temperature? Did you read that it will be on for serveral seconds at a time?
Thanks.
However, the MAX device has it own stability rating over temperature which adds to the stability (or instability) of the resistor, so for adequate overall stability you subtract the stability of the MAX (5ppm/deg C) to get 15.8 ppm/deg C for the resistor: 20.8ppm-5ppm=15.8ppm
My resistor 330ohms was 15ppm like you say, so I just change it to 620ohms (because that is a standard value) or should you suggest to use two resistors to get exactly 625ohms?
I thought that if I use u resistors in parallel it would decrease stability no?
Last edited: