UJA1065TW: High-speed CAN/LIN fail-safe system basis chip

2.1 General

• Contains a full set of CAN and LIN ECU functions:
  • CAN transceiver and LIN transceiver
  • Voltage regulator for the microcontroller (3.3 V or 5.0 V)
  • Separate voltage regulator for the CAN transceiver (5 V)
  • Enhanced window watchdog with on-chip oscillator
  • Serial Peripheral Interface (SPI) for the microcontroller
  • ECU power management system
  • Fully integrated autonomous fail-safe system
• Designed for automotive applications:
  • Supports 14 V and 42 V architectures
  • Excellent ElectroMagnetic Compatibility (EMC) performance
  • ±8 kV ElectroStatic Discharge (ESD) protection Human Body Model (HBM) for off-board pins
  • ±4 kV ElectroStatic Discharge (ESD) protection IEC 61000-4-2 for off-board pins
  • ±60 V short-circuit proof CAN/LIN-bus pins
  • Battery and CAN/LIN-bus pins are protected against transients in accordance with ISO 7637-3
  • Very low sleep current
• Supports remote flash programming via the CAN-bus
• Small 6.1 mm × 11 mm HTSSOP32 package with low thermal resistance

2.2 CAN transceiver

• ISO 11898-2 and ISO 11898-5 compliant high-speed CAN transceiver
• Enhanced error signalling and reporting
• Dedicated low dropout voltage regulator for the CAN-bus:
  • Independent from microcontroller supply
  • Guarded by CAN-bus failure management
  • Significantly improves EMC performance
• Partial networking option with global wake-up feature, allows selective CAN-bus communication without waking up sleeping nodes
• Bus connections are truly floating when power is off
• SPLIT output pin for stabilizing the recessive bus level

2.3 LIN transceiver

• LIN 2.0 compliant LIN transceiver
• Enhanced error signalling and reporting
• Downward compatible with LIN 1.3 and the TJA1020

2.4 Power management

• Smart operating modes and power management modes
• Cyclic wake-up capability in Standby and Sleep mode
• Local wake-up input with cyclic supply feature
• Remote wake-up capability via the CAN-bus and LIN-bus
• External voltage regulators can easily be incorporated in the power supply system (flexible and fail-safe)
• 42 V battery-related high-side switch for driving external loads such as relays and wake-up switches
• Intelligent maskable interrupt output

2.5 Fail-safe features

• Safe and predictable behavior under all conditions
• Programmable fail-safe coded window and time-out watchdog with on-chip oscillator, guaranteeing autonomous fail-safe system supervision
• Fail-safe coded 16-bit SPI interface for the microcontroller
• Global enable pin for the control of safety-critical hardware
• Detection and detailed reporting of failures:
  • On-chip oscillator failure and watchdog alerts
  • Battery and voltage regulator undervoltages
  • CAN and LIN-bus failures (short-circuits and open-circuit bus wires)
  • TXD and RXD clamping situations and short-circuits
  • Clamped or open reset line
  • SPI message errors
  • Overtemperature warning
  • ECU ground shift (two selectable thresholds)
• Rigorous error handling based on diagnostics
• Supply failure early warning allows critical data to be stored
• 23 bits of access-protected RAM is available e.g. for logging of cyclic problems
• Reporting in a single SPI message; no assembly of multiple SPI frames needed
• Limp-home output signal for activating application hardware in case system enters Fail-safe mode (e.g. for switching on warning lights)
• Fail-safe coded activation of Software development mode and Flash mode
• Unique SPI readable device type identification
• Software-initiated system reset