Controlling LEDs


I am needing to control about 75 Infrared LED's individually of each other (can turn each on and off) through the use of the program LABVIEW. Originally I was thinking of using multiplexers to accomplish this, but I came into the issue of drawing enough current to control them. Now I believe that using an LED driver would be the best bet to do this. Are there any LED drivers out there that are capable of accomplishing this task?

Best Answer

If each individual LED draws less than around 50mA you can control them with a series of 74HC595 shift registers and ULN2803 darlington drivers (one series resistor for each LED).

You'd need 10 of each of the chips and 75 resistors (total cost = cheap). You simply shift data (bit high= on) and then transfer the data from all 75 to the output latch. If you want you could transfer data in parallel into each channel which would be faster. You can use a standard NI digital output board and one of their uber-expensive cables + breakouts.