I'm looking at my friend's notes on choosing resistor values for a simple infrared generator circuit. I don't quite understand it and was wondering if you guys could help me.
I understand how they got V(RE2) and V(comp) but I'm not sure what Isink is. Could someone please tell me where on the diagram Isink would be and how they got a value of 6mA for it? I'm not sure if they calculated that value or knew it from a datasheet.