CompactRIO is widely used in all kinds of embedded control and detection system

but it has no high precision and high integration acquisition module.In order to meet the requirements of high precision sampling applications

we designed a high precision data acquisition module with self-calibration based on CompactRIO.This module is highly integrated.Being of an area of 73.38 mm × 66.04 mm

it realizes 6-channel data acquisition of 24 bit

with the THD of better than –108 dB

and RMS noise of below 1.2 μV.The module can achieve offset calibration and gain calibration of ADC according to an internal high precision voltage source

which improves the amplitude consistency among channels.Test results demonstrate that self-calibration improves the amplitude consistency from 1.5% to 5× 10 6.