SCPS290A April   2024  – June 2024 TCAL6416R

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements
    7. 5.7 I2C Bus Timing Requirements
    8. 5.8 Switching Characteristics
    9. 5.9 Typical Characteristics
  7. Parameter Measurement Information
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Voltage Translation
      2. 7.3.2 I/O Port
      3. 7.3.3 Adjustable Output Drive Strength
      4. 7.3.4 Interrupt Output (INT)
      5. 7.3.5 Reset Input (RESET)
      6. 7.3.6 Software Reset Call
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-On Reset
    5. 7.5 Programming
      1. 7.5.1 I2C Interface
    6. 7.6 Register Maps
      1. 7.6.1 Device Address
      2. 7.6.2 Control Register and Command Byte
      3. 7.6.3 Register Descriptions
      4. 7.6.4 Bus Transactions
        1. 7.6.4.1 Writes
        2. 7.6.4.2 Reads
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Minimizing ICC When I/Os Control LEDs
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Power-On Reset Requirements
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Adjustable Output Drive Strength

The output drive strength registers allow the user to control the drive level of the GPIO. Each GPIO can be configured independently to one of the four possible current levels. By programming these bits the user is changing the number of transistor pairs or 'fingers' that drive the I/O pad. Figure 7-3 shows a simplified output stage. The behavior of the pad is affected by the Configuration register, the output port data, and the output drive strength register. When the output drive strength register bits are programmed to 01b, then only two of the fingers are active, reducing the current drive capability by 50%.

TCAL6416R Simplified Output Stage Figure 7-3 Simplified Output Stage

A function of the output drive selection causes a peak current to occur when the output switches. Reducing the current drive capability may reduce the system noise that occurs. This peak current runs through the supply and GND package inductance and creates a noise (some radiated, but more critically Simultaneous Switching Noise (SSN)). In other words, switching many outputs at the same time will create ground and supply noise. The output drive strength control through the Output Drive Strength registers allows the user to mitigate SSN issues without the need of additional external components.