SLLSG42 September   2026 TCAN944-Q1

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  ESD Ratings, IEC Specification
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Thermal Information
    6. 6.6  Power Supply Characteristics
    7. 6.7  Dissipation Ratings
    8. 6.8  Electrical Characteristics
    9. 6.9  Switching Characteristics
    10. 6.10 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Pin Description
        1. 8.3.1.1 TXD
        2. 8.3.1.2 GND
        3. 8.3.1.3 VCC
        4. 8.3.1.4 RXD
        5. 8.3.1.5 VIO
        6. 8.3.1.6 CANH and CANL
        7. 8.3.1.7 STB (Standby)
      2. 8.3.2 CAN Bus States
      3. 8.3.3 TXD Dominant Timeout (DTO)
      4. 8.3.4 CAN Bus Short-Circuit Current Limiting
      5. 8.3.5 Thermal Shutdown (TSD)
      6. 8.3.6 Undervoltage Lockout
      7. 8.3.7 Unpowered Device
      8. 8.3.8 Floating pins
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operating Modes
      2. 8.4.2 Normal Mode
      3. 8.4.3 Standby Mode
        1. 8.4.3.1 Remote Wake Request via Wake-Up Pattern (WUP) in Standby Mode
      4. 8.4.4 Driver and Receiver Function
  10. 9 Application Information Disclaimer
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 CAN Termination
      2. 9.2.2 Detailed Design Procedures
        1. 9.2.2.1 Bus Loading, Length and Number of Nodes
      3. 9.2.3 Application Curve
    3. 9.3 System Examples
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.3.6 Undervoltage Lockout

The supply pins, VCC and VIO, have undervoltage detection that places the device into a protected state. This protects the bus during an undervoltage event on either supply pin.

Table 8-1 Undervoltage Lockout - TCAN944-Q1
VCCDEVICE STATEBUSRXD PIN
> UVVCCNormalPer TXDMirrors bus
< UVVCCProtectedHigh impedance High impedance
Table 8-2 Undervoltage Lockout - TCAN944V-Q1
VCCVIODEVICE STATEBUSRXD PIN
> UVVCC> UVVIONormalPer TXDMirrors bus
< UVVCC> UVVIOSTB = High: Standby ModeWeakly biased to GNDVIO: Remote wake request
See Remote Wake Request via Wake-Up Pattern (WUP) in Standby Mode
STB = Low: Protected ModeRecessive
> UVVCC< UVVIOProtected High impedanceHigh impedance
< UVVCC< UVVIO

Once the undervoltage condition is cleared and tMODE has expired, the TCAN944-Q1 transitions to normal mode. The host controller can again send and receive CAN traffic.