SCPS226C January   2011  – August 2018 TCA4311A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  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 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
      1. 8.3.1 Rise-Time Accelerators
      2. 8.3.2 READY Digital Output
      3. 8.3.3 EN Low Current Disable
    4. 8.4 Device Functional Modes
      1. 8.4.1 Start-Up
      2. 8.4.2 Connection Circuitry
      3. 8.4.3 Missing ACK Event
        1. 8.4.3.1 System Impact
        2. 8.4.3.2 System Workaround
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 Input to Output Offset Voltage
        2. 9.2.1.2 Propagation Delays
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Resistor Pull-Up Value Selection
      3. 9.2.3 Application Curves
      4. 9.2.4 Live Insertion and Capacitance Buffering CompactPCI Application
        1. 9.2.4.1 Design Requirements
        2. 9.2.4.2 Detailed Design Procedure
        3. 9.2.4.3 Application Curves
      5. 9.2.5 Live Insertion and Capacitance Buffering PCI Application
        1. 9.2.5.1 Design Requirements
        2. 9.2.5.2 Detailed Design Procedure
        3. 9.2.5.3 Application Curves
      6. 9.2.6 Repeater/Bus Extender Application
        1. 9.2.6.1 Design Requirements
        2. 9.2.6.2 Detailed Design Procedure
        3. 9.2.6.3 Application Curves
      7. 9.2.7 Systems With Disparate Supply Voltages
        1. 9.2.7.1 Design Requirements
        2. 9.2.7.2 Detailed Design Procedure
        3. 9.2.7.3 Application Curves
  10. 10Power Supply Recommendations
  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 Community 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

9.2.6 Repeater/Bus Extender Application

Users who wish to connect two 2-wire systems separated by a distance can do so by connecting two TCA4311A back-to-back, as shown in Figure 14. The I2C specification allows for 400 pF maximum bus capacitance, severely limiting the length of the bus. The SMBus specification places no restriction on bus capacitance, but the limited impedances of devices connected to the bus require systems to remain small if rise- and fall-time specifications are to be met. The strong pull-up and pull-down impedances of the TCA4311A are capable of meeting rise- and fall-time specifications for one nano-Farad of capacitance, thus allowing much more interconnect distance. In this situation, the differential ground voltage between the two systems may limit the allowed distance, because a valid logic low voltage with respect to the ground at one end of the system may violate the allowed VOL specification with respect to the ground at the other end. In addition, the connection circuitry offset voltages of the back-to-back TCA4311A add together, directly contributing to the same problem.

TCA4311A appin7_cps226.gifFigure 14. Repeater/Bus Extender Schematic