I wanted to build a project that would have 4 output to create chasing LEDs effect
1 1 0 0
0 1 1 0
0 0 1 1
1 0 0 1
The output is the easy part (a pair of flip flop circuits can do it) but most IC do not take kindly to driving 100 LEDs per pin.
Available source is 2.5v and I plan to use white 3mm LEDs. How can I interface multiple LEDs to the chip so the current draw won't fry the chip? Also at about 2.5v (less any voltage drop if I use silicon switching device) I won't need resistor. Is there any drawback to having 100 LEDs in parallel? If one LED is going to suffer thermal runaway due to defect, it'd just burn itself out then the rest of LED would continue as normal.
I could use higher voltage and resistor but I am lousy with SMD and wiring regular 1/8w resistor in a small project is going to be a messy rat nest of nightmare. (not to mention resistor + heatshrink tubes are thicker and would require redesigning) so I am hoping to just skip the resistor.
TIA for any suggestion!