SLASEJ4C April   2017  – February 2023 PGA460

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Internal Supply Regulators Characteristics
    6. 6.6  Transducer Driver Characteristics
    7. 6.7  Transducer Receiver Characteristics
    8. 6.8  Analog to Digital Converter Characteristics
    9. 6.9  Digital Signal Processing Characteristics
    10. 6.10 Temperature Sensor Characteristics
    11. 6.11 High-Voltage I/O Characteristics
    12. 6.12 Digital I/O Characteristics
    13. 6.13 EEPROM Characteristics
    14. 6.14 Timing Requirements
    15. 6.15 Switching Characteristics
    16. 6.16 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power-Supply Block
      2. 7.3.2  Burst Generation
        1. 7.3.2.1 Using Center-Tap Transformer
        2. 7.3.2.2 Direct Drive
        3. 7.3.2.3 Other Configurations
      3. 7.3.3  Analog Front-End
      4. 7.3.4  Digital Signal Processing
        1. 7.3.4.1 Ultrasonic Echo—Band-Pass Filter
        2. 7.3.4.2 Ultrasonic Echo–Rectifier, Peak Hold, Low-Pass Filter, and Data Selection
        3. 7.3.4.3 Ultrasonic Echo—Nonlinear Scaling
        4. 7.3.4.4 Ultrasonic Echo—Threshold Data Assignment
        5. 7.3.4.5 Digital Gain
      5. 7.3.5  System Diagnostics
        1. 7.3.5.1 Device Internal Diagnostics
      6. 7.3.6  Interface Description
        1. 7.3.6.1 Time-Command Interface
          1. 7.3.6.1.1 RUN Commands
          2. 7.3.6.1.2 CONFIGURATION/STATUS Command
        2. 7.3.6.2 USART Interface
          1. 7.3.6.2.1 USART Asynchronous Mode
            1. 7.3.6.2.1.1 Sync Field
            2. 7.3.6.2.1.2 Command Field
            3. 7.3.6.2.1.3 Data Fields
            4. 7.3.6.2.1.4 Checksum Field
            5. 7.3.6.2.1.5 PGA460 UART Commands
            6. 7.3.6.2.1.6 UART Operations
              1. 7.3.6.2.1.6.1 No-Response Operation
              2. 7.3.6.2.1.6.2 Response Operation (All Except Register Read)
              3. 7.3.6.2.1.6.3 Response Operation (Register Read)
            7. 7.3.6.2.1.7 Diagnostic Field
            8. 7.3.6.2.1.8 USART Synchronous Mode
          2. 7.3.6.2.2 One-Wire UART Interface
          3. 7.3.6.2.3 Ultrasonic Object Detection Through UART Operations
        3. 7.3.6.3 In-System IO-Pin Interface Selection
      7. 7.3.7  Echo Data Dump
        1. 7.3.7.1 On-Board Memory Data Store
        2. 7.3.7.2 Direct Data Burst Through USART Synchronous Mode
      8. 7.3.8  Low-Power Mode
        1. 7.3.8.1 Time-Command Interface
        2. 7.3.8.2 UART Interface
      9. 7.3.9  Transducer Time and Temperature Decoupling
        1. 7.3.9.1 Time Decoupling
        2. 7.3.9.2 Temperature Decoupling
      10. 7.3.10 Memory CRC Calculation
      11. 7.3.11 Temperature Sensor and Temperature Data-Path
      12. 7.3.12 TEST Pin Functionality
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 UART and USART Communication Examples
    6. 7.6 Register Maps
      1. 7.6.1 EEPROM Programming
      2. 7.6.2 Register Map Partitioning and Default Values
      3. 7.6.3 REGMAP Registers
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Transducer Types
    2. 8.2 Typical Applications
      1. 8.2.1 Transformer-Driven Method
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Transducer Driving Voltage
          2. 8.2.1.2.2 Transducer Driving Frequency
          3. 8.2.1.2.3 Transducer Pulse Count
          4. 8.2.1.2.4 Transformer Turns Ratio
          5. 8.2.1.2.5 Transformer Saturation Current and Main Voltage Rating
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Direct-Driven (Transformer-Less) Method
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.4.1 Layout Guidelines

A minimum of two layers is required to a accomplish a small-form factor ultrasonic module design. The layers should be separated by analog and digital signals. The pin map of the device is routed such that the power and digital signals are on the opposing side of the analog driver and receiver pins. Consider the following best practices for PGA460 device layout in order of descending priority:

  • Separating the grounding types is important to reduce noise at the AFE input of the PGA460. In particular, the transducer sensor ground, supporting driver, and return-path circuitry should have a separate ground before being connected to the main ground. Separating the sensor and main grounds through a ferrite bead is best practice, but not required; a copper-trace or 0-Ω short is also acceptable when bridging grounds.
  • The analog return path pins, INP and INN, are most susceptible to noise and therefore should be routed as short and directly to the transducer as possible. Ensure the INN capacitor is close to the pin to reduce the length of the ground wire.
  • In applications where protection from an ESD strike on the case of the transducer is important, ground routing of the capacitor on the INN pin should be separate from the device ground and connected directly with the shortest possible trace to the connector ground.
  • The analog drive pins can be high-current, high-voltage, or both and therefore the design limitation of the OUTA and OUTB pins is based on the copper trace profile. The driver pins are recommended to be as short and direct as possible when using a transformer, and driving the primary windings with a high-current limit
  • The decoupling capacitors for the AVDD, IOREG, and VPWR pins should be placed as close to the pins as possible
  • Any digital communication should be routed away from the analog receiver pins. The IO, TXD, RXD, and SCLK pins should be routed on the opposite side of the PCB, away from of the analog signals. When the IO pin is referenced to a high-voltage VPWR, and operating at a high-speed baud rate, the trace to the connector or controller should be as direct as possible