SLLU321 July   2022

 

  1.   TCAN1043AEVM Evaluation Module User's Guide
  2.   Trademarks
  3. 1Introduction
    1. 1.1 TCAN1043A-Q1 EVM
    2. 1.2 Applications
  4. 2Test Setup and Results
    1. 2.1 Overview and Basic Operation Settings
      1. 2.1.1 Jumper Description
      2. 2.1.2 Power Supply Inputs VSUP, VCC, and VIO
      3. 2.1.3 TXD Input
      4. 2.1.4 RXD Output
      5. 2.1.5 nSTB and EN Mode Control
      6. 2.1.6 Inhibit (INH) High Voltage Output
      7. 2.1.7 CANH and CANL Bus Pins
      8. 2.1.8 WAKE Input
      9. 2.1.9 nFAULT Output
    2. 2.2 Using CAN Bus Load, Terminations, and Protection Features
    3. 2.3 Using Customer-Installable I/O Options for Current Limiting, Pull Up and Pull Down, Noise Filtering
  5. 3EVM Setup and Basic Usage
    1. 3.1 Equipment
    2. 3.2 TCAN1043A-Q1 EVM Setup
    3. 3.3 TCAN1043A-Q1 Normal Operation 500 kbps Test Results
  6. 4Schematic and Bill of Materials
    1. 4.1 TCAN1043A-Q1 EVM Schematic
    2. 4.2 TCAN1043AEVM Bill Of Materials

2.1.9 nFAULT Output

The nFAULT terminal is used to signal multiple fault condition and is available via JMP2 position 6 and TP0. Table 2-3 shows the device status indicator flags implemented to allow for the system to determine the status and diagnose the device and system. In addition to faults, the nFAULT terminal also signals wake up requests and cold power-up sequence on the VSUP battery supply terminal so the system can do any diagnostics or cold booting sequence necessary. The faults are multiplexed (ORed) to the nFAULT output.

Table 2-3 Internal and External Indicator Flags (nFAULT)
Event Flag Name Cause Indicators Flag Cleared Comment
Power up PWRON Power up on VSUP and any return of VSUP after it has been below UVVSUP nFAULT = L upon entering silent mode from standby, go-to-sleep, or sleep mode After transition to normal mode
Wake-up request WAKERQ Wake-up event on CAN bus, state transition on WAKE pin, or initial power up nFAULT = RXD = L after wake up in standby mode, go-to-sleep mode, and sleep mode After transition to normal mode, or either a UVVCC or UVVIO event Wake-up request may only be set from standby, go-to-sleep, or sleep mode. Resets timers for UVVCC or UVVIO
Wake-up source recognition WAKESR Wake-up event on CAN bus, state transition on WAKE pin, initial power up Available upon entering normal mode , nFAULT = L indicates wake from WAKE terminal, nFAULT = H indicates wake from CAN bus After four recessive to dominant edges on TXD in normal mode, leaving normal mode, or either a UVVCC or UVVIO event A LWU source flag is set on initial power up
Undervoltage UVVCC Undervoltage VCC Not externally indicated VCC returns, or Wake-up request occurs
UVVIO Undervoltage VIO Not externally indicated VIO returns, or Wake-up request occurs
UVVSUP Undervoltage VSUP Not externally indicated VSUP returns VSUP undervoltage event triggers the PWRON and WAKERQ flags upon return of VSUP
CAN bus failures CBF CANH or CANL shorted to GND, VCC, VSUP nFAULT = L in normal mode only If fault is not present for four consecutive dominant to recessive transitions or upon leaving normal mode Failure must persist for four consecutive dominant to recessive transitions
Local faults TXDCLP TXD low when CAN active mode is entered nFAULT = L upon entering silent mode from normal mode RXD = L and TXD = H, or upon transitioning into normal, standby, go-to-sleep, or sleep modes with TXD = H CAN driver reamins disabled until the TXDCLP is cleared. CAN receiver remains active during the TXDCLP fault
TXDDTO TXD dominant time out, dominant (low) signal for t ≥ tTXD_DTO CAN driver remains disabled until the TXDDTO is cleared. CAN receiver remains active during TXDDTO fault.
TXDRXD TXD and RXD pins are shorted together for t ≥ tTXD_DTO CAN driver remains disabled until the TXDRXD is cleared. CAN driver remains active during the TXDRXD fault.
CANDOM CAN bus dominant fault, when dominant bus signal received for t ≥ tBUS_DOM RXD = H, or upon transitioning into normal, standby, go-to-sleep, or sleep modes Driver remains enabled
TSD Thermal shutdown, junction temperature ≥ TTSD TJ drops below TTSD and either RXD = L and TXD = H, or upon transitioning into normal, standby, go-to-sleep, or sleep modes CAN driver remains disabled until the TSD is cleared