Solution
The PXIe-4339 has 2 modes: ratiometric and voltage. The ratiometric mode is used to provide excitation and measure from bridge-based sensors whereas the voltage mode is used to measure regular voltages. In ratiometric mode, the programmable excitation is able to be corrected through the use of remote sense lines. In voltage mode, instead of using the programmable excitation, a steady 2.5V signal is sent into the reference of the ADC to calculate the output. This is further exemplified in the following image.