If have several 1 watt LEDs that I want to drive off of a TTL gate's ouput. What can I do to increase a 74LS TTL logic chip's output fan-out (current) to be able to produce a true 5 V output that is capable of driving as much as 500 mA (or more if possible) worth of devices (at 5v)?
As a side question to this one, is it better to use a TTL chip's high output with the cathode of the LED connected to ground or vice versa (use a low output with the LED anode connected to +5 V)? Also, on which leg of the correct orientation should the current limiting resistor go, if that matters? Finally, to complicate things more, should the LEDs be connected in series or parallel for higher output?