SCPS133K December   2005  – December 2024 PCA9557

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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 I2C Interface Timing Requirements
    7. 5.7 Reset Timing Requirements
    8. 5.8 Switching Characteristics
    9. 5.9 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Functional Block Diagram
    2. 7.2 Feature Description
      1. 7.2.1 RESET
        1. 7.2.1.1 RESET Errata
          1. 7.2.1.1.1 System Impact
          2. 7.2.1.1.2 System Workaround
      2. 7.2.2 Power-On Reset
    3. 7.3 Programming
      1. 7.3.1 I2C Interface
    4. 7.4 Register Maps
      1. 7.4.1 Device Address
      2. 7.4.2 Control Register And Command Byte
      3. 7.4.3 Register Descriptions
        1. 7.4.3.1 Bus Transactions
          1. 7.4.3.1.1 Writes
          2. 7.4.3.1.2 Reads
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Detailed Design Procedure
        1. 8.2.1.1 Minimizing ICC when I/O is Used to Control LED
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Power-On Reset Errata
        1. 8.3.1.1 System Impact
  10. 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
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
7.4.3.1.1 Writes

Data is transmitted to the PCA9557 by sending the device address and setting the least-significant bit (LSB) to a logic 0 (see Figure 7-7 for device address). The command byte is sent after the address and determines which register receives the data that follows the command byte. There is no limitation on the number of data bytes sent in one write transmission (see Figure 7-9 and Figure 7-10).

PCA9557 Write to Output Port RegisterFigure 7-9 Write to Output Port Register
PCA9557 Write to Configuration or Polarity Inversion RegistersFigure 7-10 Write to Configuration or Polarity Inversion Registers