SLAA907D September   2019  – December 2021 PGA450-Q1 , PGA460 , PGA460-Q1 , TDC1000 , TDC1000-Q1 , TDC1011 , TDC1011-Q1 , TUSS4440 , TUSS4470

 

  1.   Trademarks
  2. 1What is Ultrasonic Time-of-Flight Sensing?
    1. 1.1 Principles of Ultrasound
    2. 1.2 Why Use Ultrasonic Sensing?
    3. 1.3 How Does Ultrasound Compare to Other Sensing Technologies?
    4. 1.4 Typical Ultrasonic-Sensing Applications
  3. 2Ultrasonic System Considerations
    1. 2.1 Introduction to the Ultrasonic System
    2. 2.2 The Ultrasonic Echo and Signal Processing
    3. 2.3 Transducer Types
    4. 2.4 Transducer Topologies
    5. 2.5 Transducer Frequencies
    6. 2.6 Transducer Drive (Transformer Drive & Direct Drive) and Current Limit
    7. 2.7 Pulse Count
    8. 2.8 Minimum Detection Range
  4. 3What Factors Influence Ultrasonic Sensing?
    1. 3.1 Transmission Medium
    2. 3.2 Acoustic Impedance
    3. 3.3 Radar Cross Section
    4. 3.4 Ambient Conditions (Temperature, Humidity, Debris)
    5. 3.5 Device Selection
  5. 4Additional Resources
  6. 5Revision History

2.1 Introduction to the Ultrasonic System

GUID-25F613B4-FA82-4DA2-9A3F-EDE90BC45925-low.pngFigure 2-1 Ultrasonic System Level Block Diagram

Ultrasonic systems can:

  • Be fully discrete (composed of amplifiers, filters, diodes, and other passive components)
  • Be an integrated AFE
  • Be an Application Specific Standardized Part (ASSP) with some signal processing capabilities on chip
  • Be fully integrated with an MCU on-chip

Note that transducer selection is a key factor in the overall performance of the ultrasonic module. The rest of this section discusses how to choose a transducer based on its type, topology, and frequency, as well as what optimization techniques can be used to achieve better performance.

For TI's list of recommended transducers compatible with TI ultrasonic devices, download the PGA460 Transformer and Transducer Listings zip file.