ZHCSG41B March   2017  – February 2020 TCA9802

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     Device Images
      1.      简化原理图
  4. 修订历史记录
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  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. Parameter Measurement Information
  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. 13器件和文档支持
    1. 13.1 文档支持
    2. 13.2 接收文档更新通知
    3. 13.3 支持资源
    4. 13.4 商标
    5. 13.5 静电放电警告
    6. 13.6 Glossary
  14. 14机械、封装和可订购信息

Design Requirements

The system designer must first select the correct variant of the TCA980x family for the load. In order to do this, the information in Table 6 must be known. The setup in Figure 19 is used for these example design requirements.

CL is the capacitance of the bus, including the pin capacitance of each slave device connected, and the capacitance of the board trace. It is possible to estimate the bus capacitance by summing up the pin capacitances of each slave device on the node (using 10-pF per slave is a safe estimate, since this is the maximum allowed per the I2C specification), but trace capacitance requires an estimation through simulation or by getting the capacitance per unit length from the board manufacturer.

Table 6. Design Requirements

Parameter Description Acceptable Range Example Value/Target
CL Load capacitance (bus capacitance) on B-side up to 400 pF 100 pF
tr Rise time up to 300 ns ≤ 150 ns
VCCA VCCA supply voltage 0.8 V-3.6 V 1.2 V
VCCB VCCB supply voltage 1.65 V-3.6 V 3.3 V
fSCL I2C clock frequency 400 kHz