General description
The UJA1061 fail-safe System Basis Chip (SBC) replaces basic discrete components that are common in every Electronic Control Unit (ECU) with a Controller Area Network (CAN) and a Local Interconnect Network (LIN) interface. The fail-safe SBC supports all networking applications that control various power and sensor peripherals by using fault-tolerant CAN as the main network interface and LIN as a local sub-bus.

FEATUREs and benefits
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, 24 V and 42 V architectures
   ♦ Excellent ElectroMagnetic Compatibility (EMC) performance
   ♦ ±8 kV ElectroStatic Discharge (ESD) protection Human Body Model (HBM) for off-board pins
   ♦ ±6 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
   ♦ Very low sleep current
■ Supports remote flash programming via the CAN-bus
■ Small 6.1 mm × 11 mm HTSSOP32 package with low thermal resistance

CAN transceiver
■ ISO 11898-3 compliant fault-tolerant 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
■ Ground shift detection

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

Power management
■ Smart operating modes and power management modes
■ Cyclic wake-up capability in Standby and Sleep modes
■ 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

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
   ♦ 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
■ 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