TJA1042T,118

The TJA1042T,118 from Nexperia is a high-speed CAN bus transceiver that provides the interface between a CAN protocol controller and the physical CAN bus, supporting both classical CAN (up to 1Mbps) and CAN FD (Flexible Data Rate, up to 5Mbps). The device is optimized for 12V automotive battery systems and provides three operating modes: Normal mode for active communication, Silent mode (listen-only) where the receiver listens to the bus but the driver is disabled to avoid bus loading, and Standby mode with only 15uA current consumption for battery-saving sleep states. The Silent mode is particularly useful for diagnostic and monitoring applications where a node must observe bus traffic without affecting it. In Standby mode, the receiver can detect bus activity and wake up the microcontroller via the RXD pin, enabling low-power system designs. The CANH and CANL bus pins are protected against electrostatic discharge (ESD) to +/-8kV per IEC 61000-4-2, and against short-circuit voltages from -27V to +40V, covering all automotive fault conditions including battery reverse and load dump. The device features automatic thermal shutdown that disables the driver when junction temperature exceeds the threshold, protecting the device from bus contention or wiring faults. The TJA1042T is pin-compatible with the earlier TJA1040 and TJA1050, allowing easy upgrades from classical CAN to CAN FD. The ,118 suffix indicates Nexperia’s tape-and-reel packaging.

The TJA1042T,118 operates as a high-speed CAN physical layer transceiver. Key subsystems include: (1) Driver Section – converts the TXD logic input to differential bus signals on CANH and CANL; a dominant TXD (low) drives CANH high and CANL low (approximately 3.5V and 1.5V, 2V differential); a recessive TXD (high) releases both lines (approximately 2.5V on both, 0V differential); the driver is disabled in Silent and Standby modes; (2) Receiver Section – monitors the differential voltage on CANH/CANL and outputs the result on RXD; dominant bus (>0.9V differential) drives RXD low; recessive bus (<0.5V differential) drives RXD high; the receiver remains active in Silent mode but the driver is disabled; in Standby mode, a low-power receiver monitors for bus wake-up patterns; (3) Mode Control – the STB (standby) pin selects the operating mode; STB high = Normal/Silent mode (depending on SPLIT pin); STB low = Standby mode; the mode transition is controlled by the host MCU; (4) CAN FD Support – the driver and receiver are designed for signal integrity at data rates up to 5Mbps with controlled edge rates and minimal bit timing distortion; the loop delay is specified for CAN FD bit timing requirements; (5) Protection – the bus pins have internal ESD clamp diodes rated for +/-8kV; series diodes protect against reverse battery; thermal shutdown disables the driver at approximately 165C; the split pin (when available) provides a common-mode stabilization voltage of VCC/2 for bus termination networks.

• Automotive CAN FD gateway: 5Mbps CAN FD communication between ECUs with listen-only diagnostic mode
• Body controller: manage door, window, and lighting nodes on CAN bus with 15uA standby for battery preservation
• Industrial CAN: high-speed CAN FD for factory automation with 5Mbps burst data transfers
• Diagnostic tool: Silent mode allows non-intrusive bus monitoring without loading the network