The OPAx607 devices have a wide operating voltage range of 2.2 V to 5.5 V with a maximum quiescent current of 1 mA. The availability of the inbuilt shutdown function enables designers to power cycle the front-end signal chain, reducing the net quiescent current even further. The minimum operating voltage range of 2.2 V proves to be very suitable for battery-powered and power sensitive applications such as the ultrasonic-based flow meters. The high GBW of the OPAx607 devices enable the gain stages and the ADC drive stages to be designed and combined, thereby reducing component count. A schematic similar to that of Figure 9-12 can be used in ultrasonic flow meters for the front-end signal chain.
The Ultrasonic sensing subsystem reference design for gas flow measurement design guide has a detailed design procedure for ultrasonic-based sensing for gas flow measurement. The OPAx607 devices are very suitable op amps for the discrete front-end design described in this design guide.