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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?

MagicalToast92
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    Is there ever a case where you would need all 75 LEDs on simultaneously? Since they are IR, I wouldn't expect your application to be able to take advantage of persistence of vision. – JYelton Sep 10 '14 at 19:24
  • How fast do you need to switch them? What is the expected drive current? What is your output hardware and how is it connected to Labview? – venny Sep 10 '14 at 19:40
  • Please post the datasheet for the IR LEDs you intend to use. Are you intending to 'pulse' the IR LEDs at a much higher current than their continuous current rating? What hardware are you intending to use to communicate between the computer running LABVIEW and the IR LEDs, or are you running LABVIEW on a computer which has digital output? – gbulmer Sep 10 '14 at 20:16
  • Covered in Best way to control 130 - 140 LEDS with Arduino Uno 32/64 bit led drivers? - "There is actually at least one 132-LED driver IC, the [AS1130* 132 LED driver with PWM](http://www.ams.com/eng/Products/Lighting-Management/LED-Driver-ICs/AS1130)*" – Anindo Ghosh Sep 11 '14 at 03:25

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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.

Spehro Pefhany
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  • Each LED draws a max of 50mA and a minimum of 10mA with volatage needs of a minimum of 1.2V and a Max of 1.6V. I;m trying to research how to control these LEDS's independent of eachother? (as in one button controls one LED on/off) – MagicalToast92 Sep 11 '14 at 03:43
  • I'm sure it can be done in LABVIEW if you have a minimum of three digital outputs (data, serial clock, register clock). ISTR shift registers in LABVIEW, but I try to avoid this platform.. – Spehro Pefhany Sep 11 '14 at 04:20
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TI TLC5926 is the chip you're looking for... They are serial, so chain them together and talk to them like shift registers.

vicatcu
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