Another application of the
TMUX7219 is in the ultrasonic sensing gas meter.
Ultrasonic sensing of gas flow uses the time of flight (ToF) of an ultrasonic wave and
its dependency and behavior in the medium using two transducer pairs for upstream and
downstream paths.
Figure 8-3 shows a circuit example utilizing the MSP430FR6043 MCU, high voltage
low distortion operational amplifiers (THS3091), along with
TMUX7219, 2:1 precision switches. The
TMUX7219 are needed to select the Rx and Tx path of the transducer. The
TMUX7219 offers low on-state resistance and causes a
very low signal distortion. The break-before-make feature allows transferring of a
signal from one port to another, with a minimal signal distortion. This device also
offers a low charge injection which makes this device suitable for high-performance
audio and data acquisition systems.