I am going through the calculations for the ONET4201LD and I am running into an issue with the RMODSET calculation. From the datasheet page 20, equation 14 states the following.....
Rmodset = 265V/36.3mA x (1+ 4000ppm/DegC x (25DegC - 60DegC) = 6.3K Ohms.
If you do the above math the number comes nowhere near the 6.3K ohms. One thing I am suspicious about is the 265V. I would have thought that this voltage should be 3.3V. If you plug in 3.3V instead of 265V you get 12.6K Ohms... which is still double the 6.3K Ohms that equation 14 states. Am I missing something here?
Also, in the above equation, 60 is subtracted from 25 which would make the value negative! The ppm/DegC number in my datasheet is shown as negative. Should the 4000ppm/DegC number above be negative also?
If I am misinterpreting the equation please let me know. Otherwise I need to know the correct way to calculate Rmodset.
Thank you,
Michael Nycz