Tool/software:
Perhaps a quick edit of this document would be prudent. This is what I found on Page 5:
Assume that you expect your supply to operate in a −40°C to 85°C environment. From , you know that you need to multiply the minimum CTR by a factor of about 0.7 at 85°C. If you select the “A” version of the 817, your minimum CRT can now be as low as 56%. Dividing the result of Equation 1 by 0.56 tells you that you may require at least 4.96mA of LED current, not including the effects of bias current. From, you can see that the bias-current effects at 4.96mA are negligible.
From figure 2, you know...
CTR
From figure 3, you know...
