National Instruments AT-MIO-64F-5, User Manual

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Chapter 2 Configuration and Installation
© National Instruments Corporation 2-7 AT-MIO-64F-5 User Manual
the configuration memory register and Table 4-9 in Chapter 4, Register Map and Descriptions .
The results of this configuration are as follows.
¥ One of channels 0 through 7 or 16 through 39 is tied to the positive (+) input of the PGIA.
¥ One of channels 8 through 15 or 40 through 63 is tied to the negative (-) input of the PGIA.
¥ Multiplexer control is configured to control up to 32 input channels.
¥ AI SENSE may be driven by the board analog input ground or left unconnected.
Considerations for using the DIFF input configuration are discussed in the Signal Connections
section later in this chapter. Figures 2-7 and 2-8 show schematic diagrams of this configuration.
RSE Input (64 Channels)
RSE input means that all input signals are referenced to a common ground point that is also tied
to the analog input ground of the AT-MIO-64F-5 board. The negative (-) input of the differential
input amplifier is tied to the analog ground. This configuration is useful when measuring
floating signal sources. See the
Types of Signal Sources section later in this chapter for more
information. With this input configuration, the AT-MIO-64F-5 can monitor up to 64 different
analog input signals. This configuration is selected via software. See the configuration memory
register and Table 4-9 in Chapter 4,
Register Map and Descriptions . The results of this
configuration are as follows:
¥ The negative (-) input of the PGIA is tied to the PGIA signal ground.
¥ Multiplexer outputs are tied together into the positive (+) input of the PGIA.
¥ Multiplexer control is configured to control up to 64 input channels.
¥ AI SENSE may be driven by the board analog input ground or left unconnected.
Considerations for using the RSE configuration are discussed in the Signal Connections section
later in this chapter. Figure 2-9 shows a schematic diagram of this configuration.
NRSE Input (64 Channels)
NRSE input means that all input signals are referenced to the same common-mode voltage, but
this common-mode voltage can float with respect to the analog ground of the AT-MIO-64F-5
board. This common-mode voltage is subsequently subtracted by the input PGIA. This
configuration is useful when measuring ground-referenced signal sources. See the
Types of
Signal Sources section later in this chapter for more information.