SCPS124H September   2006  – March 2021 PCA9534

PRODUCTION DATA  

  1. 1 Features
  2. 2 Description
  3. 3 Revision History
  4. 4 Description (Continued)
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Resistance Characteristics
    5. 7.5 Electrical Characteristics
    6. 7.6 I2C Interface Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Functional Block Diagram
    2. 9.2 Device Functional Modes
      1. 9.2.1 Power-On Reset
      2. 9.2.2 I/O Port
      3. 9.2.3 Interrupt Output ( INT)
        1. 9.2.3.1 Interrupt Errata
          1. 9.2.3.1.1 Description
          2. 9.2.3.1.2 System Impact
          3. 9.2.3.1.3 System Workaround
    3. 9.3 Programming
      1. 9.3.1 I2C Interface
      2. 9.3.2 Register Map
        1. 9.3.2.1 Device Address
        2. 9.3.2.2 Control Register And Command Byte
        3. 9.3.2.3 Register Descriptions
        4. 9.3.2.4 Bus Transactions
          1. 9.3.2.4.1 Writes
          2. 9.3.2.4.2 Reads
  10. 10Application Information Disclaimer
    1. 10.1 Application Information
      1. 10.1.1 Typical Application
        1. 10.1.1.1 Design Requirements
          1. 10.1.1.1.1 Minimizing ICC When The I/O Controls Leds
  11. 11Power Supply Recommendations
    1. 11.1 Power-On Reset Requirements
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.3.2.2 Control Register And Command Byte

Following the successful acknowledgment of the address byte, the bus master sends a command byte, which is stored in the control register in the PCA9534. Two bits of this command byte state the operation (read or write) and the internal register (input, output, polarity inversion or configuration) that will be affected. This register can be written or read through the I2C bus. The command byte is sent only during a write transmission.

Once a command byte has been sent, the register that was addressed continues to be accessed by reads until a new command byte has been sent.

GUID-1FBD8BB7-1061-4086-92D9-A701AE8AF33B-low.gifFigure 9-7 Control Register Bits
Table 9-3 Command Byte
CONTROL
REGISTER BITS		COMMAND BYTE (HEX)REGISTERPROTOCOLPOWER-UP
DEFAULT
B1B0
000x00Input PortRead bytexxxx xxxx
010x01Output PortRead/write byte1111 1111
100x02Polarity InversionRead/write byte0000 0000
110x03ConfigurationRead/write byte1111 1111