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

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Configuration and Installation Chapter 2
AT-MIO-64F-5 User Manual 2-18 © National Instruments Corporation
Extended Analog Input Subconnector Signal Descriptions
Pin Signal Name Reference Description
1-24 ACH<16..27> AI GND Analog Input Channels 16 through 27 and
ACH<40..51>51 AI GND 40 through Ð In the differential mode, the
input is configured for up to 32 channels,
with ACH<16..27> and ACH<40..51>
representing differential Channels 16
through 27 and 40 through 51. In the RSE
and NRSE modes, the input is configured
for up to 64 channels with ACH<16..27>
as Channels 16 through 27 and
ACH<40..51>as Channels 40 through 51.
25 AI SENSE AI GND Analog Input Sense Ð This pin serves as
the reference mode when the board is in
NRSE configuration. If desired, this
signal can be programmed to be driven by
the board analog input ground.
26 AI GND N/A Analog Input Ground Ð These pins are the
reference point for single-ended
measurements and the bias current return
point for differential measurements.
27-50 ACH<28..39> AI GND Analog Input Channels 28 through 39 and
ACH<52..63>63 AI GND 52 through Ð In the DIFF mode,
ACH<28..39> and ACH<52..63>
represent differential Channels 28 through
39. In the RSE and NRSE modes,
ACH<28..39> represent Channels 28
through 39, and ACH<52..63> represent
Channels 52 through 63.
The signals on the connector are classified as analog input signals. Signal connection guidelines
for each of these groups are given in the following section.
Analog Input Signal Connections
Pins 1 through 19 of the MIO subconnector and pins 1 through 50 of the extended analog input
subconnector are analog input signal pins. Pins 1 and 2 of the MIO subconnector and pin 26 of
the extended analog input subconnector are AI GND signal pins. AI GND is an analog input
common signal that is routed directly to the ground tie point on the AT-MIO-64F-5. These pins
can be used for a general analog power ground tie point to the AT-MIO-64F-5 if necessary.
Pin 19 of the MIO subconnector and pin 25 of the extended analog input subconnector comprise
the AI SENSE signal. In NRSE mode, AI SENSE is connected internally to the negative (-)
input of the AT-MIO-64F-5 PGIA. In the DIFF and RSE modes, this signal is driven by
AI GND or left unconnected. Each subconnector individually buffers the AI SENSE signal with