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NI 9683 User Guide and Specifications
Simultaneous Analog Input
The NI 9683 provides connections for 16 pseudo-differential analog input channels.
Each channel has an AI+ and AI- pin to which you can connect a voltage signal. AI- is internally
connected to the isolated ground reference through a high value resistor.
Connecting Differential and Single-Ended Voltage Signals to the
NI 9683
You can connect grounded or floating signal sources to the NI 9683. Connect the positive
voltage signal to AI+ and the negative voltage signal to the AI-.
Figure 9.
Connecting a Differential Voltage Signal to a Simultaneous AI Channel
Figure 10.
Connecting a Single-Ended Voltage Signal to a Simultaneous AI Channel
NI 9683 Circuitry
The NI 9683 analog channels share a common ground that is isolated from other parts of the
board. The NI 9683 protects each channel from overvoltages. Refer to the
for more information about overvoltage protection. The incoming analog signal on each channel
is buffered and conditioned by the differential amplifier and then sampled by a 12-bit ADC.
Each channel has an independent track-and-hold amplifier and ADC that allow you to sample
and convert all 16 channel simultaneously.
Connecting Current Sensors to the NI 9683
You can connect current sensors to the NI 9683 using a termination resistor to convert the current
measurement to a single-ended voltage measurement.
Connect the current sensor output to AI+ and the external power supply COM to the current
sensor common pin (CS COM) on the NI 9683.
NI 96
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