SCPS266B March   2017  – February 2020 TCA9802

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin 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 Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Integrated Current Source
      2. 9.3.2 Ultra-Low Power Consumption
      3. 9.3.3 No Static-Voltage Offset
      4. 9.3.4 Active-High Repeater Enable Input
      5. 9.3.5 Powered Off High Impedance I2C Bus Pins on A-Side
      6. 9.3.6 Powered-Off Back-Power Protection for I2C Bus Pins
      7. 9.3.7 Clock Stretching and Multiple Master Arbitration Support
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device Operation Considerations
        1. 9.4.1.1 B-Side Input Low (VIL/IILC/RILC)
          1. 9.4.1.1.1 VILC & IILC
          2. 9.4.1.1.2 RILC
        2. 9.4.1.2 Input and Output Leakage Current (IEXT-I/IEXT-O)
          1. 9.4.1.2.1 IEXT-I
          2. 9.4.1.2.2 IEXT-O
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Device Selection Guide
      2. 10.1.2 Special Considerations for the B-side
        1. 10.1.2.1 FET or Pass-Gate Translators
        2. 10.1.2.2 Buffered Translators/Level-shifters
    2. 10.2 Typical Application
      1. 10.2.1 Single Device
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
        3. 10.2.1.3 Application Curves
      2. 10.2.2 Buffering Without Level-Shifting
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
        3. 10.2.2.3 Application Curve
      3. 10.2.3 Parallel Device Use Case
        1. 10.2.3.1 Design Requirements
        2. 10.2.3.2 Detailed Design Procedure
        3. 10.2.3.3 Application Curves
      4. 10.2.4 Series Device Use Case
        1. 10.2.4.1 Design Requirements
        2. 10.2.4.2 Detailed Design Procedure
        3. 10.2.4.3 Application Curve
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

10.2.1 Single Device

The typical application for the TCA980x family is to be used as a buffering translator, where the VCCA and VCCB are at different values in order to level-shift the I2C bus voltages.

It is critical to note that there are no external sources of current allowed on the B-side ports, since this can affect device operation as shown in the IEXT-I section.

TCA9802 apps_single_trans.gifFigure 19. Typical Level-Shifting Application Example (Master on A-side)

NOTE

Decoupling capacitors are not shown to keep the illustration simple. Decoupling capacitors (1 µF and 0.1 µF) must be placed close to each power supply pin.

As shown in Figure 20, the I2C master can be on the B-side, and that it is ok to have VCCA > VCCB. The only requirements are that no external source of current (pull-up resistor or current source) be on the B-pins of the TCA980x, and that both VCCA/VCCB values are within the recommended range. As a note, since the EN pin is referenced to the VCCA supply voltage, when the master is on the A-side, the system designer must ensure that the enable pin voltage is pulled up to VCCA (either with an external or the internal pull-up resistor) to ensure that the device is enabled.

TCA9802 apps_single_trans_rev.gifFigure 20. Typical Level-Shifting Application Example (Master on B-side)

NOTE

Decoupling capacitors are not shown to keep the illustration simple. Decoupling capacitors (1 µF and 0.1 µF) must be placed close to each power supply pin.