SLLSFO8C May   2024  – November 2025 TCAN2450-Q1 , TCAN2451-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  IEC ESD Ratings
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Thermal Information
    6. 6.6  Supply Characteristics
    7. 6.7  Electrical Characteristics
    8. 6.8  Timing Requirements
    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  CAN FD Transceiver
        1. 8.3.1.1 Driver and Receiver Function
      2. 8.3.2  VCC1 Regulator
        1. 8.3.2.1 Functional Description of Buck Regulator
          1. 8.3.2.1.1 Fixed Frequency Peak Current Mode Control
          2. 8.3.2.1.2 Minimum ON-Time, Minimum OFF-Time, and Frequency Foldback
          3. 8.3.2.1.3 Overcurrent and Short Circuit Protection
          4. 8.3.2.1.4 Soft Start
        2. 8.3.2.2 Buck Regulator Functional Modes
          1. 8.3.2.2.1 Buck Shutdown Mode
          2. 8.3.2.2.2 Buck Active Modes
      3. 8.3.3  VCC2 Regulator
        1. 8.3.3.1 VCC2 Short to Battery Protection
      4. 8.3.4  Reset Function (nRST Pin)
      5. 8.3.5  LIMP Function
      6. 8.3.6  High Side Switches
      7. 8.3.7  WAKE and ID Inputs
        1. 8.3.7.1 ID Functionality
      8. 8.3.8  Interrupt Function (nINT Pin)
      9. 8.3.9  SPI Communication
        1. 8.3.9.1 Cyclic Redundancy Check
        2. 8.3.9.2 Chip Select Not (nCS):
        3. 8.3.9.3 SPI Clock Input (SCK):
        4. 8.3.9.4 SPI Data Input (SDI):
        5. 8.3.9.5 SPI Data Output (SDO):
      10. 8.3.10 SW Pin
      11. 8.3.11 GFO Pin
      12. 8.3.12 Wake Functions
        1. 8.3.12.1 CAN Bus Wake Using RXD Request (BWRR) in Sleep Mode
        2. 8.3.12.2 Local Wake Up (LWU) via WAKEx Input Terminal
          1. 8.3.12.2.1 Static Wake
          2. 8.3.12.2.2 Cyclic Sensing Wake
        3. 8.3.12.3 Cyclic Wake
        4. 8.3.12.4 Selective Wake-up
          1. 8.3.12.4.1 Selective Wake Mode (TCAN2451-Q1)
          2. 8.3.12.4.2 Frame Detection
          3. 8.3.12.4.3 Wake-Up Frame (WUF) Validation
          4. 8.3.12.4.4 WUF ID Validation
          5. 8.3.12.4.5 WUF DLC Validation
          6. 8.3.12.4.6 WUF Data Validation
          7. 8.3.12.4.7 Frame Error Counter
          8. 8.3.12.4.8 CAN FD Frame Tolerance
          9. 8.3.12.4.9 8Mbps Filtering
      13. 8.3.13 Protection Features
        1. 8.3.13.1 Fail-safe Features
          1. 8.3.13.1.1 Sleep Mode Through Sleep Wake Error
        2. 8.3.13.2 Device Reset
        3. 8.3.13.3 Floating Terminals
        4. 8.3.13.4 TXD Dominant Time Out (DTO)
        5. 8.3.13.5 CAN Bus Short Circuit Current Limiting
        6. 8.3.13.6 Thermal Shutdown
        7. 8.3.13.7 Under and Over Voltage Lockout and Unpowered Device
          1. 8.3.13.7.1 Under-Voltage
            1. 8.3.13.7.1.1 VSUP and VHSS Under-voltage
            2. 8.3.13.7.1.2 VCC1 Under-Voltage
            3. 8.3.13.7.1.3 VCC2 Under-voltage
            4. 8.3.13.7.1.4 VCAN Under-voltage
          2. 8.3.13.7.2 VCC1 and VCC2 Over-voltage
          3. 8.3.13.7.3 VCC1 and VCC2 Short Circuit
        8. 8.3.13.8 Watchdog
          1. 8.3.13.8.1 Watchdog Error Counter and Action
          2. 8.3.13.8.2 Watchdog SPI Programming
            1. 8.3.13.8.2.1 Watchdog Configuration Lock Mechanism
              1. 8.3.13.8.2.1.1 Watchdog Configuration in SPI Two-byte Mode
          3. 8.3.13.8.3 Watchdog Timing
          4. 8.3.13.8.4 Question and Answer Watchdog
            1. 8.3.13.8.4.1 WD Question and Answer Basic Information
            2. 8.3.13.8.4.2 Question and Answer Register and Settings
            3. 8.3.13.8.4.3 WD Question and Answer Value Generation
              1. 8.3.13.8.4.3.1 Answer Comparison
              2. 8.3.13.8.4.3.2 Sequence of the 2-bit Watchdog Answer Counter
              3. 8.3.13.8.4.3.3 Question and Answer WD Example
                1. 8.3.13.8.4.3.3.1 Example Configuration for Desired Behavior
                2. 8.3.13.8.4.3.3.2 Example of performing a question and answer sequence
        9. 8.3.13.9 Bus Fault Detection and Communication
      14. 8.3.14 Customer EEPROM Programming
    4. 8.4 Device Functional Modes
      1. 8.4.1 Init Mode
      2. 8.4.2 Normal Mode
      3. 8.4.3 Standby Mode
      4. 8.4.4 Restart Mode
      5. 8.4.5 Fail-safe Mode
        1. 8.4.5.1 SBC Faults
        2. 8.4.5.2 CAN Transceiver Faults
      6. 8.4.6 Sleep Mode
  10. 9 Device Register Tables
    1. 9.1 Device Registers
  11. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 CAN BUS Loading, Length and Number of Nodes
      2. 10.1.2 CAN Termination
        1. 10.1.2.1 CAN Bus Biasing
      3. 10.1.3 Device Brownout Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedures
        1. 10.2.2.1 CAN Detailed Design Procedure
      3. 10.2.3 Application Curves
    3. 10.3 Power Supply Recommendations
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 CAN Transceiver Physical Layer Standards:
      2. 11.1.2 EMC Requirements:
      3. 11.1.3 Conformance Test Requirements:
      4. 11.1.4 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

8.4 Device Functional Modes

The TCAN245x-Q1has several SBC operating modes: normal, standby, sleep, restart and fail-safe. The first three mode selections are made by the SPI register, 8'h10[2:0]. Fail-safe mode if enabled is entered due to various fault conditions. TheTCAN245x-Q1 automatically goes from sleep to restart and then to standby mode when receiving a WUP or LUP event. When selective wake is enabled, the device looks for a WUF and if not received the TCAN2451-Q1remains in sleep mode. See Table 8-27 for the various modes and what parts of the device are active during each mode.
Table 8-27 Mode Overview
Block Restart Sleep Standby Normal Fail-safe
nINT High (VCC1 present)
off others		 High (VCC1 present)
High-Z others		 Active Active High-Z
GFO High (VCC1 present)
off others		 High-Z Active Active High-Z
SW Off Wake capable/Off Active Active Wake capable/Off
HSSx Off Off - HSS4 can be on if WAKE pins setup for cyclic sensing As Programmed As Programmed Off - HSS4 can be on if WAKE pins setup for cyclic sensing
LIMP (Open-drain active low) Same as previous state unless from fail-safe mode. Off (high from external pull-up) from fail-safe mode unless WD error and then Low

High (LIMP_SLP_FLT_EN =0b);Enabled (LIMP_SLP_FLT_EN =1b)

 Previous state prior to entering STBY Previous state prior to entering normal mode Low
WAKEx Off On (default); programmable off On (default); programmable off On (default); programmable off On (default); programmable off
CRXD High (VCC1 present) High (VCC1 present)
High-Z others		 Transceiver configuration dependent Transceiver configuration dependent High-Z
nRST Low Low unless VCC1 programmed to be on in sleep mode, then high. High High Off
SPI Off Active if VCC1 present Active Active Off
Watchdog Off Off (default); programmable on

when VCC1 is on

 Default on with long first pulse but programmable off

- Timeout only

 Active Off
Low Power CAN RX Default on for Wake capable Default on for Wake capable On if Wake capable On if Wake capable Default on for Wake capable
CAN Transceiver Off Off Programmable

- Receiver only

 Programmable Off
VCC1 Ramping Off (default); programmable on On (default); programmable off On Off
VCC2 Ramping Off (default); programmable on On (default); programmable off On (default); programmable off Off
TCAN2450-Q1 TCAN2451-Q1 Device State Diagram Figure 8-53 Device State Diagram
Note:
  1. Fail-safe mode is exited after tREGOFF expires and a wake event has taken place if the fault has cleared. Wake event is not needed to exit fail-safe mode if VCC1_CFG = 01b (VCC1 is always ON). If the fail-safe mode is entered due to a TSD event, the device exits the fail-safe mode 1s after temperature falls below TSDF threshold without needing a wake event. If cyclic wake is turned ON in fail-safe mode, device automatically wakes up according to the selected timer intervals to check if the fault is cleared.
  2. SWE timer starts upon entering fail-safe mode and if timer times out the device transitions to sleep mode regardless of VCC1 configuration.
  3. Restart counter increments when entered from Normal or Standby modes
  4. Transition from Restart mode to Standby mode can take place if:
    • VCC1 > UVCC1R and
    • tNRST_TOG expires (in case of WD failure or entering from fail-safe mode) OR tRSTN_act expires (entering from sleep mode or power-up)
  5. If OVCC1_ACTION (8'h0C[6]) is set to 1b and there is an OVCC1 event, the device only sets the OVCC1 interrupt and stays in the current SBC mode.
  6. If VCC1 is ON in Sleep mode, the transition from Sleep mode to Restart mode due to wake event is enabled only when VCC1_SLP_ACT =1b. If instead VCC1_SLP_ACT = 0b (default), the device only sets a wake interrupt and indicates the wake-up via CRXD pin.
TCAN2450-Q1 TCAN2451-Q1 Selective Wake Enabled Sleep Mode Figure 8-54 Selective Wake Enabled Sleep Mode
Note:

For the state diagrams, by default SPI is off in sleep mode. SPI can be configured to work in sleep mode which includes selective wake sub state as shown in Figure 8-54.