Floating Signal Inputs Offer New Application Advantages - Data Translation TEMPpoint DT9871U User Manual

Floating Signal Inputs Offer New Application
Advantages
Precision measurement systems are often limited in that all inputs are connected to a single
ground. Typically, multiplexer input configurations are set up this way, since all signal inputs
are connected to the same return. Even differential input configurations use the same ground
reference. The result is that accuracy and flexibility for accurate measurements can be severely
compromised when noise or common mode voltage is present (see
Figure 41: In multiplexed systems, all inputs are connected to a signal ground, which can cause
errors when noise or common mode voltage is present.
Crosstalk from one input signal can easily be reflected onto another input. The design
movement to an A/D per channel can help this problem. But that is not sufficient in many
cases (see Figure 42).
About ISO-Channel Technology
Figure 41).
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