Taking Differential Measurements

For differential signals, connect the positive lead of the signal to the AI+ terminal, and the negative lead to the AI- terminal.

Figure 8. Connecting a Differential Voltage Signal

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The differential input mode can measure ±20 V signals in the ±20 V range. However, the maximum voltage on any one pin is ±10 V with respect to GND. For example, if AI 1 is +10 V and AI 5 is -10 V, then the measurement returned from the device is +20 V.

Figure 9. Example of a Differential 20 V Measurement

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Connecting a signal greater than ±10 V on either pin results in a clipped output.

Figure 10. Exceeding ±10 V on AI Returns Clipped Output

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