Crosstalk
PrintCrosstalk is any unwanted signal on one channel due to a signal on another channel. Crosstalk is the ratio, in dB, of the level of the interference on the affected channel to the actual level of the interfering signal at a specified load impedance and over a specific frequency. The crosstalk does not include any settling time error.
Units:
dB
Crosstalk in Data Acquisition
Crosstalk behavior is common to DAQ devices with scanning front ends because there is capacitance at the output of the channel multiplexer on a device. When you scan, a DAQ device can store voltage from one channel on the capacitor and pass that voltage to the next channel in the scan. If the impedance of the source on the second channel is not low enough, the source cannot charge the capacitance to its value in the allotted time, and crosstalk occurs.
To avoid crosstalk during data acquisition, do not scan any faster than necessary. Set the interchannel delay to as large a value as possible and use low impedance sources. You also can scan a grounded channel in between other channels to discharge the capacitance.
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