ZHCSOO3A May   2021  – December 2021

PRODUCTION DATA  

  1. 1 特性
  2. 2 应用
  3. 3 说明
  4. 4 Revision History
  5. 5 说明（续）
  6. 6 Pin Configurations and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 ESD Ratings IEC Specification
    4. 7.4 Recomended Operating Conditions
    5. 7.5 Thermal Information
    6. 7.6 Power Supply Characteristics
    7. 7.7 Electrical Characteristics
    8. 7.8 Switching Characteristics
    9. 7.9 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  VSUP Pin
      2. 9.3.2  VFLT Pin
      3. 9.3.3  Digital Inputs and Outputs
        1. 9.3.3.1 TXD Pin
        2. 9.3.3.2 RXD Pin
        3. 9.3.3.3 TS Pin
      4. 9.3.4  Digital Control and Timing
      5. 9.3.5  VIO Pin
      6. 9.3.6  GND
      7. 9.3.7  INH Pin
      8. 9.3.8  WAKE Pin
      9. 9.3.9  CAN Bus Pins
      10. 9.3.10 Local Faults
        1. 9.3.10.1 TXD Dominant Timeout (TXD DTO)
        2. 9.3.10.2 Thermal Shutdown (TSD)
        3. 9.3.10.3 Under/Over Voltage Lockout
        4. 9.3.10.4 Unpowered Devices
        5. 9.3.10.5 Floating Terminals
        6. 9.3.10.6 CAN Bus Short Circuit Current Limiting
        7. 9.3.10.7 Sleep Wake Error Timer
    4. 9.4 Device Functional Modes
      1. 9.4.1 Operating Mode Description
        1. 9.4.1.1 Normal Mode
        2. 9.4.1.2 Standby Mode
        3. 9.4.1.3 Sleep Mode
          1. 9.4.1.3.1 Remote Wake Request via Wake-Up Pattern (WUP)
          2. 9.4.1.3.2 Local Wake-Up (LWU) via WAKE Input Terminal
        4. 9.4.1.4 Fail-safe Mode
      2. 9.4.2 CAN Transceiver
        1. 9.4.2.1 CAN Transceiver Operation
        2. 9.4.2.2 CAN Transceiver Modes
          1. 9.4.2.2.1 CAN Off Mode
          2. 9.4.2.2.2 CAN Autonomous: Inactive and Active
          3. 9.4.2.2.3 CAN Active
        3. 9.4.2.3 Driver and Receiver Function Tables
        4. 9.4.2.4 CAN Bus States
  10. 10Application Information
    1. 10.1 Application Information Disclaimer
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 Bus Loading, Length and Number of Nodes
      2. 10.2.2 Detailed Design Procedures
        1. 10.2.2.1 CAN Termination
    3. 10.3 Application Curves
  11. 11Power Supply Requirements
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 接收文档更新通知
    3. 13.3 支持资源
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 术语表
  14. 14Mechanical, Packaging, and Orderable Information

9.3.10.1 TXD Dominant Timeout (TXD DTO)

While the CAN driver is in active mode a TXD DTO circuit prevents the local node from blocking network communication in event of a hardware or software failure where TXD is held dominant longer than the time out period tTXD_DTO. The TXD DTO circuit is triggered by a falling edge on TXD. If no rising edge is seen before the time out constant of the circuit, tTXD_DTO, expires the CAN driver is disabled releasing the bus lines to the recessive level. This keeps the bus free for communication between other nodes on the network. The CAN driver is re-activated on the next dominant to recessive transition on the TXD terminal, thus clearing the dominant time out. The high-speed receiver and RXD terminal will reflect what is on the CAN bus during a TXD DTO fault. The TS terminal in driven low during a TXD DTO fault.

GUID-E30FD5B4-ABA8-4236-A6D4-891B4E2508AC-low.gifFigure 9-2 Timing Diagram for TXD DTO

The minimum dominant TXD time allowed by the TXD DTO circuit limits the minimum possible transmitted data rate of the device. The CAN protocol allows a maximum of eleven successive dominant bits (on TXD) for the worst case, where five successive dominant bits are followed immediately by an error frame. The minimum transmitted data rate may be calculated using the minimum tTXD_DTO time and the maximum number of successive dominant bits (11 bits).

Equation 1. Minimum Data Rate = 11 bits / tTXD_DTO = 11 bits / 1.2 ms = 9.2 kbps