I have two questions about LED's and would appreciate some insight. First, I want to build a "high power" LED array with 100 LEDs but I’m not sure what the smartest layout design for the LED's would be. I could do 100 LEDs in series but then if one dies they all will stop working. I could do one LED driver with 10 strings and 10 LEDs each (if I could find one). Or, it seems like having a separate LED driver for each 10 LED string would be the smartest was to go.
Second, I’d like to know if I calculated the LED R(d) correctly. The charts for this LED aren’t the typical ones I’ve seen. The all have pulse times instead of continuous on times (which is how I plan to use them). I calculated R(d) with the values on the datasheet was are :
https://www.digikey.com/products/en?keywords=SFH 4547
V(f) = 1.5V
I(f)= 100mA
1.5/.1=15 Ohms = R(d)
Is this a reasonable R(d) value?
Second, I’d like to know if I calculated the LED R(d) correctly. The charts for this LED aren’t the typical ones I’ve seen. The all have pulse times instead of continuous on times (which is how I plan to use them). I calculated R(d) with the values on the datasheet was are :
https://www.digikey.com/products/en?keywords=SFH 4547
V(f) = 1.5V
I(f)= 100mA
1.5/.1=15 Ohms = R(d)
Is this a reasonable R(d) value?