ELECTRICAL CONDUCTIVITY MODULE

摘要

A driving circuit for a fluid conductivity sensor includes a pulse width modulation unit, an H-bridge, first and second differential amplifiers, and an analog-to-digital converter (ADC). The pulse width modulation unit generates two opposing driving signals. The H-bridge receives the two opposing driving signals and generates two H-bridge outputs. The first differential amplifier includes first inputs connected in parallel to a shunt resistor. One of the first inputs is coupled to the two generated H-bridge outputs. The second differential amplifier includes second inputs connected in parallel with a pair of terminals having a sensor attached thereto. One of the second inputs and the pair of terminals receive a signal from the other of the two generated H-bridge outputs. The ADC receives a first output representative of a first current from the first differential amplifier; and a second output representative of a second current from the second differential amplifier.

主权项

1. A driving circuit for a fluid conductivity sensor, the circuit comprising:
a pulse width modulation unit configured to generate two opposing driving signals; an H-bridge configured to:
receive the two opposing driving signals; andgenerate at least two H-bridge outputs; a first differential amplifier including first inputs connected in parallel to a shunt resistor, wherein one of the first inputs is configured to receive one of the at least two generated H-bridge outputs; a second differential amplifier including second inputs connected in parallel with a pair of terminals having a sensor attached thereto, wherein one of the second inputs and the pair of terminals are configured to receive the other of the at least two generated H-bridge outputs; and an analog-to-digital converter (ADC) configured to receive:
a first output representative of a first current from the first differential amplifier; anda second output representative of a second current from the second differential amplifier.