"dirty" DC power input to the USB-6225

[dv01]

I am considering the USB-6225 for measuring some low-level differential signals.  However, for my configuration the only power I have conveniently available is +12VDC, which unfortunately is shared with several fans.  What are the practical limits for the power input ripple and noise for the USB-6225?  Is there a specification for the max power supply ripple and noise?

[Jake_G]

Hey dv01,

The USB-6225 does not have a specification specifically called "Ripple and Noise", but if you check the specification guide for the USB-622x series, on page 10 there is a section called "Power Requirements" that has some good information.

Under the "Caution" in that section, it states "USB-622x devices must be powered with NI offered AC adapter or a National Electric Code (NEC) Class 2 DC source that meets the power requirements for the device and has appropriate safety certifcation marks for country of use."

So it looks like you may want to make sure that your power supply meets those requirements.