This question is related to my another question here.
In crux, I would like to sink current of TLP521 via 74HC595n shift register. The TLP521 is connected with a resistance such that the current is limited to 16mA.
My question is that if the current is limited to 16mA and the TLP521 "led" consumes it, then how much is left over for the 74HC595N to sink?
I understand that if "led" was not in place (consider a short), only then the 74HC595N would see a total 16mA current and would struggle to sink it ( as it can sink only 6mA current). But in this case, the LED would "eat" (sorry but this is my analogy of current) the current any a tiny amount might be left over for 74hc595 to sink.