NXP Semiconductors UJA1075ATW/3V3/WDJ

Overview

UJA1075ATW/3V3/WDJ from NXP Semiconductors is a high-speed CAN/LIN core System Basis Chip (SBC) integrating a 3.3 V/250 mA microcontroller voltage regulator, ISO 11898-2-compliant CAN transceiver, LIN 2.2A/SAE J2602 transceiver, advanced window/timeout watchdog, and SPI interface - designed for automotive ECU power and communication management in engine control, body electronics, and ADAS sensor nodes.

For engineers reviewing the UJA1075ATW/3V3/WDJ datasheet, UJA1075ATW/3V3/WDJ pinout, UJA1075ATW/3V3/WDJ application, or UJA1075ATW/3V3/WDJ equivalent, key selection considerations include its 3.3 V V1 regulator accuracy (±2 %), dual wake-up inputs with configurable sampling, SPLIT pin for CAN bus stabilization, limp home output for fail-safe activation, and HTSSOP32 package with exposed thermal pad for automotive-grade thermal reliability.

Technical Context

The UJA1075ATW/3V3/WDJ implements a state-machine-based system controller managing Off/Standby/Normal/Sleep/Overtemp modes with deterministic transitions triggered by VBAT thresholds, wake events, or register writes. Its CAN transceiver uses a dedicated low-dropout V2 regulator (5 V) independent of V1, improving EMC and enabling floating bus pins during power-off.

It features full-duplex SPI (16-bit) with read-only register access, on-chip oscillator for watchdog timing, and programmable wake biasing (WBIAS) with 16 ms/64 ms sampling options - all coordinated via Mode_Control, WD_and_Status, and Int_Control registers to enable remote flash programming, cyclic wake-up, and detailed fault reporting including V1/V2 undervoltage, wake source identification, and overtemperature shutdown.

Key Specifications

Pinout & Package

Package: HTSSOP32 (SOT549-1), plastic thermal enhanced thin shrink small outline package; 32 leads; body width 6.1 mm; lead pitch 0.65 mm; exposed die pad soldered to PCB ground for optimal thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar core SBC applications.

Compared with UJA1076ATW/3V3/WDJ, the UJA1075ATW/3V3/WDJ omits VEXT supervision but retains identical CAN/LIN performance, 3.3 V regulation, and watchdog behavior - making it optimal for cost-sensitive ECU designs without external 5 V rail monitoring. Against TJA1044GT/3, it delivers full SBC integration versus discrete CAN-only functionality.

Availability

UJA1075ATW/3V3/WDJ is available at Aetrix Electronics and suitable for automotive engine control, body electronics, and ADAS sensor nodes requiring stable component supply across extended temperature ranges (−40 °C to +150 °C), long lifecycle commitments, and AEC-Q100 Grade 1 qualification.

Supply support for UJA1075ATW/3V3/WDJ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with leadership in CAN, LIN, and automotive power management ICs.

The UJA1075ATW/3V3/WDJ belongs to NXP's System Basis Chip product line, engineered specifically for automotive ECU consolidation - reducing discrete component count while delivering robust power regulation, fault-tolerant communication, and fail-safe behavior in harsh vehicle environments.

FAQ

What is the primary function of the UJA1075ATW/3V3/WDJ in an automotive ECU?

The UJA1075ATW/3V3/WDJ serves as a core System Basis Chip that integrates a 3.3 V/250 mA microcontroller regulator, ISO 11898-2 CAN transceiver, LIN 2.2A transceiver, advanced watchdog, and SPI interface. It replaces discrete power and communication components in automotive ECUs, enabling centralized power management, network interfacing, and fail-safe supervision - all within a single HTSSOP32 package qualified to AEC-Q100 Grade 1.

Does the UJA1075ATW/3V3/WDJ support both CAN and LIN communication simultaneously?

Yes, the UJA1075ATW/3V3/WDJ supports concurrent CAN and LIN operation in Normal mode. Its CAN transceiver complies with ISO 11898-2:2003 and ISO 11898-5:2006, while the LIN transceiver meets LIN 2.2A and SAE J2602 standards. Both interfaces can be independently configured via SPI registers (e.g., STBCC and STBCL bits) to operate in Active or Lowpower mode with bus wake-up detection enabled.

How does the watchdog in the UJA1075ATW/3V3/WDJ differ from basic timeout watchdogs?

The UJA1075ATW/3V3/WDJ implements a programmable advanced watchdog with Window, Timeout, and Off modes - clocked by an on-chip oscillator independent of V1/V2. Unlike basic timeout watchdogs, its Window mode requires triggers within a defined time window (first half of period) to avoid reset, preventing premature resets due to timing jitter. The default period is 128 ms, adjustable from 8 ms to 4096 ms via NWP bits in the WD_and_Status register.

Can the UJA1075ATW/3V3/WDJ operate during automotive battery cranking conditions?

Yes, the UJA1075ATW/3V3/WDJ is designed for automotive cranking resilience. Its V1 regulator operates down to 4.5 V VBAT (per ISO 7637 and ISO 16750-2), maintaining stable 3.3 V output to the microcontroller. The V2 regulator sustains CAN transceiver operation down to 5.5 V VBAT. Both regulators include undervoltage warning and reset functions, ensuring controlled behavior during voltage sags.

What is the purpose of the SPLIT pin on the UJA1075ATW/3V3/WDJ?

The SPLIT pin (Pin 24) on the UJA1075ATW/3V3/WDJ provides a common-mode stabilization output for the CAN bus. It connects to the center tap of a split termination resistor (e.g., two 60 Ω resistors) between CANH and CANL, reducing bus reflections and improving recessive-level stability - especially critical in longer or branched CAN networks. This feature enhances signal integrity without requiring external active components.