UJA1079ATW/5V0WD,1

Specialized Overview

The UJA1079ATW/5V0WD,1 is a LIN core System Basis Chip (SBC) from NXP Semiconductors designed for automotive Electronic Control Units. It integrates a LIN transceiver compliant with LIN 2.2A and SAE J2602 standards, alongside a scalable 5 V voltage regulator delivering up to 250 mA for microcontroller supply. The device includes an advanced independent watchdog with window and timeout modes, a full-duplex Serial Peripheral Interface (SPI), two local wake-up input ports, and a limp home output port. Packaged in a 32-lead HTSSOP plastic thermal enhanced thin shrink small outline package (SOT549-1), it supports low-power concepts and safe system start-up behavior.

Specialized Feature Summary

• Integrates a LIN transceiver compliant with LIN 2.2A, SAE J2602, and downward compatible with earlier versions, featuring low slope mode for optimized EMC performance.
• Provides a scalable 5 V voltage regulator capable of delivering up to 250 mA, extendable via external PNP transistor for improved heat distribution.
• Includes an advanced independent watchdog supporting Window and Timeout modes with an on-chip oscillator, ensuring safe system operation.
• Features a full-duplex 16-bit SPI interface for configuration, control, and diagnosis, along with detailed status reporting capabilities.

Specialized Applications

• Automotive Electronic Control Units (ECU) requiring LIN bus connectivity
• Power and sensor peripheral control networks using LIN as a local sub-bus
• Microcontroller power management systems with integrated reset and watchdog functions

Specialized Procurement Notes

Verify the specific ordering suffix '5V0' confirms the 5 V regulator version and 'WD' indicates the inclusion of the watchdog feature. Ensure the package type matches the required HTSSOP32 footprint. Confirm RoHS compliance and dark green status if environmental regulations apply to your assembly process. Cross-reference the datasheet revision date to ensure compatibility with your design specifications.

Specialized Selection Notes

Select this component when a single-chip solution for LIN communication and microcontroller power regulation is required. The 5 V output version is suitable for systems needing higher current capacity or specific voltage levels compared to the 3.3 V variant. The integrated watchdog eliminates the need for external monitoring circuits, simplifying PCB layout. Consider the external PNP transistor option if thermal dissipation exceeds the internal regulator's capability.

Specialized Part Context

The UJA1079A belongs to NXP's LIN core System Basis Chip family, distinct from the CAN/LIN dual-interface UJA1078A. While the UJA1078A combines high-speed CAN and dual LIN interfaces, the UJA1079A focuses exclusively on LIN functionality. This specialization allows for optimized cost and pin count in applications where only LIN connectivity is necessary, maintaining similar power management and safety features like the watchdog and voltage regulation.

Specialized Replacement Considerations

Direct replacements within the same family include the UJA1079ATW/3V0WD,1 for 3.3 V regulator requirements. For applications requiring CAN integration, the UJA1078A series may be considered, though pinouts and functionalities differ significantly. Verify electrical parameters and pin compatibility before substituting with non-NXP components.

Specialized FAQ

What LIN standards does the UJA1079A support?

The UJA1079A features a LIN transceiver compliant with LIN 2.2A and SAE J2602. It is also downward compatible with LIN 2.2, LIN 2.1, LIN 2.0, LIN 1.3, LIN 1.2, LIN 1.1, and LIN 1.0.

How can the voltage regulator current capability be extended?

The 250 mA voltage regulator can be extended by connecting an external PNP transistor. This allows for increased current capability and better heat distribution across the PCB.

What watchdog modes are available in the WD variant?

The UJA1079ATW/5V0WD,1 supports Window mode, Timeout mode, and Off mode for its advanced independent watchdog. The watchdog period is programmable via the SPI interface.