Chapter 2
Configuration and Installation
© National Instruments Corporation
2-9
AT-MIO-16 User Manual
Input Mode
The AT-MIO-16 has three different input modes—differential (DIFF) input, referenced single-
ended (RSE) input, and nonreferenced single-ended (NRSE) input. The single-ended input
configurations use 16 channels. The DIFF input configuration uses eight channels. You may
find it helpful to refer to the Analog Input Signal Connections section in Chapter 3, Signal
Connections, which contains diagrams showing the signal paths for the three configurations.
The multiplexer-mode selection jumpers configure the analog input channels as 16 single-ended
inputs or 8 differential inputs. When single-ended mode is selected, the outputs of the two
multiplexers are tied together and routed to the positive (+) input of the instrumentation
amplifier. The negative (-) input of the instrumentation amplifier is tied to the AT-MIO-16
ground for RSE input or to the analog return of the input signals via the AI SENSE input on the
I/O connector for NRSE input. When DIFF mode is selected, the output of MUX0 is routed to
the positive (+) input of the instrumentation amplifier, and the output of MUX1 is routed to the
negative (-) input of the instrumentation amplifier.
DIFF Input (Eight Channels, Factory Setting).
DIFF input means that each input signal has its own reference, and the difference between each
signal and its reference is measured. The signal and its reference are each assigned an input
channel. With this input configuration, the AT-MIO-16 can monitor eight different analog input
signals. You select the DIFF input configuration by setting jumpers W6 and W9 shown in
Table 2-6.
Table 2-6. DIFF Input Configuration (Factory Setting)
Jumper
Settings
Description
W6
H
F
D
B
G
E
C
A
Jumper is placed in standby position or can be discarded.
AISENSE is tied to the instrumentation amplifier output ground point.
Channels 0 through 7 are tied to the positive input of the instrumentation
amplifier. Channels 8 through 15 are tied to the negative input of the
instrumentation amplifier.
W9
DIFF
SE
•
The multiplexer is configured to control eight input channels.
RSE Input (16 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-16 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 in Chapter 3, Signal Connections, for
more information. With this input configuration, the AT-MIO-16 can monitor 16 different
analog input signals. You select the RSE input configuration by setting jumpers W6 and W9 as
shown in Table 2-7.