Half-bridge and full-bridge modes – National Instruments NI 9219 User Manual

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NI 9219 Operating Instructions

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for lead wire resistance. Refer to Figure 9 for an illustration of the
connections.

Figure 9. Connections in 2-Wire Resistance and Quarter-Bridge Modes

Half-Bridge and Full-Bridge Modes

Half-Bridge and Full-Bridge modes use the internal voltage
excitation to set the input range of the ADC and return voltage
readings that are proportional to the excitation level. The internal
excitation voltage is nominally 2.5 V but it varies based on the
resistance of the sensor. Refer to the

Specifications

section for

more information about excitation levels.

In Half-Bridge mode, the HI input is referenced to EX–.
In Full-Bridge mode, the ADC reads the HI and LO inputs
differentially. Refer to Figure 10 for an illustration of the
connections.

LO

R

Wire

Wire

I

ADC

I

HI

NI 9219

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