NXP Semiconductors TJA1042T/1J

Overview

TJA1042T/1J from NXP Semiconductors is a high-speed CAN transceiver compliant with ISO 11898-2:2016 and SAE J2284-1 to J2284-5, delivering differential transmit/receive capability for automotive HS-CAN networks. It operates at supply voltages from 4.5 V to 5.5 V, supports CAN FD fast-phase data rates up to 5 Mbit/s, and features a low-current Standby mode (10–15 μA) with bus wake-up capability - enabling power-sensitive ECUs in 12 V/24 V systems.

For engineers reviewing the TJA1042T/1J datasheet, TJA1042T/1J pinout, TJA1042T/1J application, or TJA1042T/1J equivalent, key selection criteria include its AEC-Q100 qualification, ±58 V bus fault tolerance, SPLIT pin for recessive-level stabilization, and SO8 package compatibility with legacy TJA1040 designs.

Technical Context

The TJA1042T/1J implements the physical layer of high-speed CAN per ISO 11898-2:2016, supporting both classical CAN and CAN FD fast phase up to 5 Mbit/s. Its differential receiver threshold (0.5–0.9 V) and hysteresis (50–200 mV) ensure robust noise immunity in automotive EMI environments, while internal slope control minimizes electromagnetic emission.

It operates in two modes: Normal mode (STB = LOW), where full TX/RX functionality is active with typical ICC = 5 mA (recessive) or 45 mA (dominant); and Standby mode (STB = HIGH), where only a low-power wake-up receiver remains active, drawing ≤15 μA and detecting dominant bus states longer than 0.5–3 μs via RXD.

Key Specifications

Pinout & Package

Package: SO8 (SOT96-1), plastic small outline, 8-lead, 3.9 mm body width - compatible with standard PCB assembly and legacy TJA1040 footprints.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed CAN transceiver applications.

Compared with TJA1042T/3, the TJA1042T/1J offers identical performance and pinout but targets different logistics channels; versus TJA1042BT, it retains the SPLIT pin for recessive-level stabilization in 5 V systems - making it the preferred choice for cost-sensitive, thermally demanding, or legacy-compatible automotive nodes.

Availability

TJA1042T/1J is available at Aetrix Electronics and suitable for automotive body control modules, ADAS sensor nodes, electric powertrain controllers, and instrument cluster displays requiring stable component supply across long product lifecycles.

Supply support for TJA1042T/1J 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 leader focused on automotive, industrial, IoT, and communication infrastructure solutions, with deep expertise in secure connectivity and embedded processing.

The TJA1042 series belongs to NXP's third-generation high-speed CAN transceiver portfolio, engineered specifically for automotive ECU designs requiring low-power standby, robust EMC/ESD performance, and seamless CAN FD migration from legacy CAN networks.

FAQ

What is the primary function of the SPLIT pin on the TJA1042T/1J?

The SPLIT pin on the TJA1042T/1J outputs 0.5×VCC in Normal mode to stabilize the recessive common-mode voltage on the CAN bus when used with a split termination network. This reduces electromagnetic emission in networks with DC leakage paths (e.g., from dormant ECUs) and improves signal integrity at high data rates like 5 Mbit/s CAN FD. In Standby mode or with VCC off, the SPLIT pin is floating and should be left unconnected if unused. The TJA1042T/1J uses this pin instead of VIO, distinguishing it from VIO-equipped variants.

Does the TJA1042T/1J support CAN FD, and what is its maximum data rate?

Yes, the TJA1042T/1J fully supports CAN FD according to ISO 11898-2:2016 and SAE J2284-1 to J2284-5, with guaranteed timing for data rates up to 5 Mbit/s in the fast phase. Its propagation delay (65–125 ns) and tight timing symmetry (±40 ns) ensure reliable bit sampling at these speeds. The transceiver does not implement protocol logic - it handles only the physical layer - so CAN FD frame handling depends on the connected microcontroller's CAN controller. The TJA1042T/1J maintains full compatibility with classical CAN (125 kbit/s to 1 Mbit/s) as well.

How does the TJA1042T/1J enter and exit Standby mode?

The TJA1042T/1J enters Standby mode when STB is driven HIGH, reducing supply current to 10–15 μA while enabling bus wake-up detection via RXD. It exits Standby mode only when STB is actively pulled LOW - even if a wake-up pulse is detected on the bus, the transceiver remains in Standby until STB transitions. This prevents unintended mode changes during transient bus activity. Additionally, undervoltage on VCC (below 3.5–4.5 V) forces automatic Standby entry, and recovery requires both VCC restoration and STB assertion. The TJA1042T/1J implements this behavior consistently across its operating temperature range.

What protection features does the TJA1042T/1J include for automotive environments?

The TJA1042T/1J integrates multiple automotive-grade protections: ±58 V fault tolerance on CANH/CANL pins per ISO 7637-2; ±8 kV HBM ESD robustness on bus lines; TXD dominant time-out (0.3–5 ms) to prevent bus lockup; bus dominant time-out in Standby mode (0.3–5 ms); undervoltage detection on VCC and VIO; and thermal shutdown at 190 °C. These features collectively ensure reliable operation during load dump, jump start, electrostatic discharge, MCU failure, and overheating - meeting AEC-Q100 Grade 0 requirements. The TJA1042T/1J delivers fail-safe behavior across all supply conditions without external components.

Is the TJA1042T/1J pin-compatible with earlier NXP CAN transceivers like the TJA1040?

Yes, the TJA1042T/1J is backwards compatible with the TJA1040 in 5 V microcontroller systems, sharing the same SO8 package, identical pinout (including SPLIT instead of VIO), and compatible voltage thresholds. It improves upon the TJA1040 with better EMC/ESD performance, lower standby current (15 μA vs. ~30 μA), and CAN FD timing support. No PCB redesign is required for drop-in replacement in existing TJA1040 layouts - the TJA1042T/1J maintains mechanical and electrical compatibility while adding functional enhancements. However, users should verify timing margins in high-speed CAN FD applications due to updated propagation characteristics.