NI PCI-MIO-16E-1 & NI PCI-6070E digital outputs to scb-68 to electrical circuit

[michiganwolverine5974]

I am currently designing a circuit and trying to interface the NI PCI-MIO-16E-1 & NI PCI-6070E DAQ's and the SCB-68 to my small circuit. The outputs are 0vdc (low) to 5vdc (High). From what I underdstand the NI PCI-MIO-16E-1 & NI PCI-6070E are the same when it comes to the 5 volt digital outputs? Also will the current be enough to turn on a LED on a PS2501-4 or a 4N38 Octocoupler? If not, what would I need to do to amplify the current. Or if you have any suggestions on resistors, capacitiors, etc. please let me know. Thanks!!

[Cooking_Up_Code]

Hello,

You are correct in your understanding that the NI PCI-MIO-16E-1 & NI PCI-6070E function the same the same way. You can read more about their output currents and other specifications in this link.

http://www.ni.com/pdf/manuals/370725c.pdf

In regards to your LED and optocoupler configuration, it looks like you should be able to get sufficient current to drive your LED. According to the spec sheet of that product I found below for the PS2501-4 optococoupler, it has an IF Current of 10mA, which your DAQ cards should be able to provide.

http://www.mouser.com/ds/2/286/ps2501-34138.pdf

I hope this helps, have a great day.

Paul C

[michiganwolverine5974]

Thank you for your reply!

The If of the photocoupler I am using is 10mA. But the DAQ only outputs +/-5mA. How will this be sufficent enought? Please let me know your thought. Thank you!

[Cooking_Up_Code]

The +/-5mA output is for the 2 analog outputs on your device. If you look under the DI/O modules, you can see under output high voltage it has (IOH=-13mA), which means that it will be sufficient enough to drive your 10mA in either high voltage or low voltage mode.

Paul C

[michiganwolverine5974]

Ok that makes sense. I had a 700 ohm resistor in series with opto, so given that information, a 500 ohm would probably be better. But a 700 should be sufficent. Do you think this should be sufficent enough? Thank you for your help!

R= 5.00V / .010 A = 500 ohm

I= 5.00V / 700 ohm = 7mA

[Cooking_Up_Code · Accepted solution]

You are correct in your thinking! From a 5 volt source, a 500 ohm resistance in series with your LED will provide enough current drive by the ohm's law math you have already provided.

Paul C

[michiganwolverine5974]

Thank you for your help! its grealy appreciated!!