Learn about making analog input measurements with the USB-6451.

Analog Input Range
Input range refers to the set of input voltages that an analog input channel can digitize with the specified accuracy. The NI-PGIA amplifies or attenuates the AI signal depending on the input range. You can individually program the input range of each AI channel on your USB-6451.
Working Voltage Range
The NI programmable gain instrumentation amplifier (NI-PGIA) operates normally by amplifying signals of interest while rejecting common-mode signals under certain conditions.
Analog Input Terminal Configurations
The USB-6451 supports three analog input terminal configurations: differential mode, referenced single-ended mode, and non-referenced single-ended mode.
Dual-Channel Scanning
The USB-6451 uses dual-channel scanning mode to sample both channels of a differential pair as two separate single-ended channels.
Analog Input Data Acquisition Methods
When performing analog input measurements, you either can perform software-timed or hardware-timed acquisitions.
Analog Input Signal Connections
You can connect floating signal sources and ground-referenced signal sources to the USB-6451.
Analog Input Timing Engine
The USB-6451 has a flexible timing engine.
Analog Input Timing Signals
The USB-6451 features six analog input timing signals.
Analog Triggering
You can configure the analog trigger circuitry of the USB-6451 to monitor any analog input channel from which you acquire data.
Onboard Temperature Sensing
You can connect a twisted pair of thermocouples to any analog input channel in differential, NRSE, or RSE mode to measure temperature.

USB-6451 and USB-6451 (OEM) User Manual

20-Bit, 1 MS/s/ch (16 AI, 2 AO, 16 DIO) mioDAQ, USB Multifunction I/O Device