SLOS346O MARCH   2001  – April 2018 SN65HVD230 , SN65HVD231 , SN65HVD232

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Equivalent Input and Output Schematic Diagrams
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
    1.     Pin Functions
  8. 8 Specifications
    1. 8.1  Absolute Maximum Ratings
    2. 8.2  ESD Ratings
    3. 8.3  Recommended Operating Conditions
    4. 8.4  Thermal Information
    5. 8.5  Electrical Characteristics: Driver
    6. 8.6  Electrical Characteristics: Receiver
    7. 8.7  Switching Characteristics: Driver
    8. 8.8  Switching Characteristics: Receiver
    9. 8.9  Switching Characteristics: Device
    10. 8.10 Device Control-Pin Characteristics
    11. 8.11 Typical Characteristics
  9. 9 Parameter Measurement Information
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1 Vref Voltage Reference
      2. 10.3.2 Thermal Shutdown
    4. 10.4 Device Functional Modes
      1. 10.4.1 High-Speed Mode
      2. 10.4.2 Slope Control Mode
      3. 10.4.3 Standby Mode (Listen Only Mode) of the HVD230
      4. 10.4.4 The Babbling Idiot Protection of the HVD230
      5. 10.4.5 Sleep Mode of the HVD231
      6. 10.4.6 Summary of Device Operating Modes
  11. 11Application and Implementation
    1. 11.1 Application Information
      1. 11.1.1 CAN Bus States
    2. 11.2 Typical Application
      1. 11.2.1 Design Requirements
        1. 11.2.1.1 CAN Termination
        2. 11.2.1.2 Loop Propagation Delay
        3. 11.2.1.3 Bus Loading, Length and Number of Nodes
      2. 11.2.2 Detailed Design Procedure
        1. 11.2.2.1 Transient Protection
        2. 11.2.2.2 Transient Voltage Suppressors
      3. 11.2.3 Application Curve
    3. 11.3 System Example
      1. 11.3.1 ISO 11898 Compliance of SN65HVD23x Family of 3.3 V CAN Transceivers
        1. 11.3.1.1 Introduction
        2. 11.3.1.2 Differential Signal
          1. 11.3.1.2.1 Common Mode Signal
        3. 11.3.1.3 Interoperability of 3.3-V CAN in 5-V CAN Systems
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Related Links
    2. 14.2 Receiving Notification of Documentation Updates
    3. 14.3 Community Resources
    4. 14.4 Trademarks
    5. 14.5 Electrostatic Discharge Caution
    6. 14.6 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

11.2.1.3 Bus Loading, Length and Number of Nodes

The ISO11898 Standard specifies up to 1 Mbps data rate, maximum bus length of 40 meters, maximum drop line (stub) length of 0.3 meters and a maximum of 30 nodes. However, with careful network design, the system may have longer cables, longer stub lengths, and many more nodes. Many CAN organizations and standards have scaled the use of CAN for applications outside the original ISO11898 standard. They have made system level trade-offs for data rate, cable length, and parasitic loading of the bus. Examples of some of these specifications are ARINC825, CANopen, CAN Kingdom, DeviceNet and NMEA200.

A high number of nodes requires a transceiver with high input impedance and wide common mode range such as the SN65HVD23x CAN family. ISO11898-2 specifies the driver differential output with a 60 Ω load (two 120 Ω termination resistors in parallel) and the differential output must be greater than 1.5 V. The SN65HVD23x devices are specified to meet the 1.5 V requirement with a 60 Ω load, and additionally specified with a differential output voltage minimum of 1.2 V across a common mode range of –2 V to 7 V via a 167 Ω coupling network. This network represents the bus loading of 120 SN65HVD23x transceivers based on their minimum differential input resistance of 40 kΩ. Therefore, the SN65HVD23x supports up to 120 transceivers on a single bus segment with margin to the 1.2 V minimum differential input voltage requirement at each node. For CAN network design, margin must be given for signal loss across the system and cabling, parasitic loadings, network imbalances, ground offsets and signal integrity thus a practical maximum number of nodes may be lower. Bus length may also be extended beyond the original ISO11898 standard of 40 meters by careful system design and data rate tradeoffs. For example, CANopen network design guidelines allow the network to be up to 1 km with changes in the termination resistance, cabling, less than 64 nodes and significantly lowered data rate.

This flexibility in CAN network design is one of the key strengths of the various extensions and additional standards that have been built on the original ISO11898 CAN standard. In using this flexibility comes the responsibility of good network design.