UJA1079TW/5V0/WD:1

Specialized Overview

The UJA1079TW/5V0/WD:1 is a LIN core System Basis Chip (SBC) from NXP Semiconductors, designed to replace discrete components in Electronic Control Units (ECUs). It integrates a LIN transceiver compliant with LIN 2.1 and SAE J2602, a scalable 5 V voltage regulator delivering up to 250 mA for microcontrollers, and an advanced independent watchdog with Window and Timeout modes. The device features a full-duplex Serial Peripheral Interface (SPI), two local wake-up input ports, and a limp home output port. It operates within a battery supply range of 4.5 V to 28 V and is housed in a 32-lead HTSSOP package.

Specialized Feature Summary

• Integrates a LIN transceiver compliant with LIN 2.1, LIN 2.0, and SAE J2602 standards, featuring low slope mode for optimized EMC performance.
• Includes a scalable 5 V voltage regulator capable of delivering up to 250 mA, extendable via external PNP transistor for improved heat distribution.
• Features an advanced independent watchdog supporting Window, Timeout, and Off modes with an on-chip oscillator.
• Provides comprehensive system control through a full-duplex SPI interface, two local wake-up inputs, and a limp home output port.

Specialized Applications

• Automotive electronic control units requiring LIN bus communication
• Power management systems for sensor peripherals
• Microcontroller power-up and power-down functionality in ECUs

Specialized Procurement Notes

Verify the exact ordering suffix against the manufacturer's current documentation, as variations exist between tape-and-reel and tube packaging formats. Confirm that the specific part number matches the required regulatory compliance status and package type before finalizing procurement orders.

Specialized Selection Notes

Select this component when a single-chip solution for LIN communication and power regulation is required. Ensure the application utilizes a microcontroller compatible with the integrated watchdog and SPI interface. Verify that the 5 V regulator output meets the specific power requirements of the target microcontroller and peripheral circuits.

Specialized Part Context

The UJA1079 series serves as a dedicated LIN core System Basis Chip, consolidating essential ECU functions into a single package. It complements other NXP interface solutions by providing robust power management and diagnostic capabilities specifically tailored for Local Interconnect Network applications in automotive environments.

Specialized Replacement Considerations

Direct replacements include UJA1079TW/3V3/WD for 3.3 V regulator variants or UJA1079TW/5V0 without the watchdog feature. Cross-family alternatives like the UJA1078A offer CAN/LIN integration but differ significantly in architecture and pinout compatibility.

Specialized FAQ

What are the supported watchdog operating modes?

The UJA1079 supports three watchdog modes: Window mode, Timeout mode, and Off mode. These can be configured via the Mode_Control register and the WDOFF pin.

How does the voltage regulator handle high load currents?

The internal voltage regulator delivers up to 250 mA. For higher current capabilities and better heat distribution, an external PNP transistor can be connected to the VEXCTRL and VEXCC pins.

What protection features are included for the LIN bus pins?

The device provides ±8 kV ESD protection (Human Body Model) and ±6 kV IEC 61000-4-2 protection on the LIN bus pin. Additionally, the LIN bus pin is short-circuit proof up to ±58 V.