[FAQ] TIDA-01386: How does PGA460 enable ultrasonic distance measurement in small form factor field transmitters

TIDA-01386 is a TI Reference Design featuring an ultrasonic distance sensor that fits in M12 housing due to its high integration and an optimized layout. The design offers an IO-Link interface to communicate with the system control, which makes it industry 4.0 ready.  The purpose of ultrasonic sensors is to detect or measure distances of an object independently from their color, transparency, or surface characteristics and from the surrounding environment. Ultrasonic sensors are able to function in harsh environments such as factories and process plants.

The PGA460 device is a highly-integrated system on-chip ultrasonic transducer driver and signal conditioner with an advanced DSP core. The device has a complimentary low-side driver pair that can drive a transducer either in a transformer based topology using a step-up transformer or in a direct-drive topology using external high-side FETs. The device can receive and condition the reflected echo signal for reliable object detection. This feature is accomplished using an analog front-end (AFE) consisting of a low-noise amplifier followed by a              programmable time-varying gain stage feeding into an ADC. The digitized signal is processed in the DSP core for both near-field and far-field object detection using time-varying thresholds.

TIDA-01386 makes use of the PGA460s high integration. It includes all signal processing components needed for US distance measurement into a single chip, making the design very compact measuring in at only 8.9 mm in width.

For additional information about this topic, please refer to section 2.3 "Design Considerations" of the User Guide for TIDA-01386.

You can also download the design files (BOM, Schematic, Gerber) for this reference design from the TIDA-01386 folder.