SCPS206B March   2014  – November 2019 TCA9543A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Application Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Electrical Characteristics
    6. 6.6 I2C Interface Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Interrupt and Reset Timing Requirements
    9. 6.9 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
      1. 8.4.1 RESET Input
      2. 8.4.2 Power-On Reset
    5. 8.5 Programming
      1. 8.5.1 I2C Interface
    6. 8.6 Register Maps
      1. 8.6.1 Device Address
      2. 8.6.2 Control Register Description
      3. 8.6.3 Control Register Definition
      4. 8.6.4 Interrupt Handling
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Power-On Reset Requirements
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  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

8.6.4 Interrupt Handling

The TCA9543A provides two interrupt inputs (one for each channel) and one open-drain interrupt output (see Table 2). When an interrupt is generated by any device, it is detected by the TCA9543A and the interrupt output is driven low. The channel does not need to be active for detection of the interrupt. A bit also is set in the control register.

Bit 4 and Bit 5 of the control register correspond to the INT0 and INT1 inputs of the TCA9543A, respectively. Therefore, if an interrupt is generated by any device connected to channel 1, the state of the interrupt inputs is loaded into the control register when a read is accomplished. Likewise, an interrupt on any device connected to channel 0 would cause bit 4 of the control register to be set on the read. The master then can address the TCA9543A and read the contents of the control register to determine which channel contains the device generating the interrupt. The master then can reconfigure the TCA9543A to select this channel, and locate the device generating the interrupt and clear it.

It should be noted that more than one device can provide an interrupt on a channel, so it is up to the master to ensure that all devices on a channel are interrogated for an interrupt.

The interrupt inputs may be used as general-purpose inputs if the interrupt function is not required.

If unused, interrupt input(s) must be connected to VCC through a pull-up resistor.

Table 2. Control Register Read (Interrupt)(1)

D7 D6 INT1 INT0 D3 D2 B1 B0 COMMAND
X X X 0 X X X X No interrupt on channel 0
1 Interrupt on channel 0
X X 0 X X X X X No interrupt on channel 1
1 Interrupt on channel 1
0 0 0 0 0 0 0 0 No channel selected; power-up/reset default state
(1) Two interrupts can be active at the same time.