Measurement of voltage USB 6008 ranging from 1mV

Hi, I'm doing a supply at an angle for an amplifier using the USB-6008. The ranges I look are - 0.5 to 0.5 V and 0.5 to 2.5 V. To generate negative tensions, I use the + 2, 5V for a reading of differential voltage output as a 'ground '. Voltage measures have a delay that varies with the voltage, given this by drawing these variations and set the output to data acquisition there is still a 'noise' of +/-1 mv so that it is clear from this parcel of tension against the sample number:

It seems that at some point the values are being rounded up to the nearest millivolt. I need to get to a resolution of 0.5 mV for my device, it will be possible with the USB-6008?

The AO USB-600 x has a range from 0 to + 5 V and the 12-bit resolution. 5/4096 = 1.22 mV. Absolute precision is 7 mV typical and 36.4 mV maximum full scale.  The noise of the AO is not specified.

If you measure the results with THE USB-6008, you have at least 0.5 mV, similar resolution system noise and absolute accuracy of 2.5 mV or more.

It's probably as good as you will get with the box USB-6008.

Lynn

Tags: NI Hardware

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