NXP UJA1167TK,118: A Comprehensive Technical Overview of the System Basis Chip for Automotive Networks
The relentless drive towards more connected, autonomous, and electrified vehicles has necessitated the development of highly robust and integrated electronic components. At the heart of many modern automotive network architectures lies the System Basis Chip (SBC), a class of devices that consolidate several critical functions into a single package. The NXP UJA1167TK,118 stands as a prime example of this integration, engineered specifically to serve as a highly reliable network node for LIN sub-networks within the demanding automotive environment.
This SBC is designed to provide a complete local area network (LIN) node solution, significantly reducing the component count and complexity for electronic control units (ECUs) that do not require the high bandwidth of CAN or CAN FD. Its primary role is to manage power, communication, and supervision for a connected microcontroller (MCU) or other local logic.
Core Functional Blocks and Key Features
The UJA1167TK,118 integrates several vital subsystems:
1. Voltage Regulators: The chip features a 5.0 V/3.3 V low-dropout (LDO) linear regulator with a typical output current of 120 mA. This regulator powers the external microcontroller and other circuitry, and it is equipped with over-temperature and short-circuit protection, making it exceptionally robust against electrical faults.
2. LIN Transceiver: A fully compliant LIN 2.2/SAE J2602 transceiver forms the communication core. It is designed for very low electromagnetic emission (EME) and high electromagnetic immunity (EMI), which are critical for passing stringent automotive EMC tests. The transceiver supports baud rates up to 20 kbaud and includes features like wake-up via LIN bus and a dedicated wake-up input pin.
3. Watchdog and Supervision: A key aspect of functional safety in automotive systems is ensuring the connected microcontroller operates correctly. The UJA1167 integrates a windowed watchdog timer and a voltage supervisor for the MCU's supply. This ensures the system can trigger a safe state or a controlled reset if the software fails or the supply voltage drifts out of specification.
4. Fail-Safe and Diagnostic Capabilities: The device is packed with extensive diagnostic features, including overtemperature warning, undervoltage detection on VCC and VBAT, and short-circuit diagnosis on the LIN bus. These features are essential for ISO 26262 functional safety applications, aiding in the development of systems targeting ASIL grades.
5. Low-Power Management: To minimize quiescent current and support always-on applications, the chip offers multiple power modes: Normal, Standby, Sleep, and Fail-safe. In Sleep mode, the device draws a very low quiescent current from the battery (VBAT), which is crucial for meeting the strict power consumption requirements of modern vehicles, especially when parked.
Target Applications and Benefits
The UJA1167TK,118 is ideal for a wide range of automotive body and convenience applications, including:
Door control modules
Seat control units
Steering wheel control units
Smart sensors and actuators
Any LIN-based sub-node requiring a regulated power supply
The primary benefits of using this SBC are its significantly reduced system size and cost due to high integration, enhanced system reliability through built-in protection and diagnostics, and simplified design process by providing a pre-validated solution for power and communication.
The NXP UJA1167TK,118 is a quintessential System Basis Chip that exemplifies the trend towards higher integration in automotive electronics. By combining a robust LIN transceiver, a protected voltage regulator, and comprehensive system supervision into a single, small-outline package, it provides a complete and fail-safe foundation for space-constrained LIN nodes. Its strong focus on functional safety, low power consumption, and diagnostic coverage makes it a trusted component for designing reliable ECUs that meet the rigorous standards of the automotive industry.
Keywords: System Basis Chip (SBC), LIN Transceiver, Automotive Networks, Functional Safety, Low-Power Management.
