NXP Semiconductors TJA1021T/20/C,118

Overview

TJA1021T/20/C,118 from NXP Semiconductors is an ISO 17987-4:2016 (12 V), LIN 2.x, and SAE J2602-compliant transceiver for automotive sub-networks. It operates at baud rates up to 20 kBd, features integrated 30 kΩ LIN responder termination, delivers ≤10 μA sleep current, and supports local/remote wake-up via WAKE_N or LIN bus dominant pulses. It serves as the physical layer interface between microcontroller LIN protocol controllers and the LIN bus in body electronics modules.

For engineers reviewing the TJA1021T/20/C,118 datasheet, TJA1021T/20/C,118 pinout, TJA1021T/20/C,118 application, or TJA1021T/20/C,118 equivalent, key selection criteria include LIN 2.2A compliance, 20 kBd timing performance, HVSON8 thermal resistance (54 K/W), wake-up source flag detection on TXD, and fail-safe behavior during VBAT undervoltage or thermal overload.

Technical Context

The TJA1021T/20/C,118 implements a LIN physical layer with optimized slew-rate-controlled transmitter output and hysteresis-equipped receiver input referenced to VBAT. Its internal 30 kΩ LIN-to-VBAT termination resistor enables responder operation without external components, while the open-drain RXD output signals wake-up interrupts to the MCU.

Three operating modes-Sleep (≤10 μA), Standby (450 μA typ.), and Normal (1.6 mA typ.)-are controlled by SLP_N, with automatic transition to Standby upon remote/local wake-up. Wake-up source identification (local vs. remote) is signaled via TXD's pull-down strength in Standby mode, and TXD dominant time-out disables the driver after >t_to(dom)TXD to prevent bus lockup.

Key Specifications

Pinout & Package

Package: HVSON8 (SOT782-1), 3.0 mm × 3.0 mm × 0.85 mm, leadless, thermally enhanced with exposed center pad soldered to PCB ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LIN transceiver applications.

Compared with TJA1021T/10/C,118, the TJA1021T/20/C,118 enables higher-speed LIN 2.2A networks; compared with MC33662B, it eliminates one external resistor and improves thermal performance via HVSON8's 54 K/W R_th(j-a).

Availability

TJA1021T/20/C,118 is available at Aetrix Electronics and suitable for automotive body electronics, seat control systems, and roof modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TJA1021T/20/C,118 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 specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The TJA1021 series is part of NXP's automotive LIN transceiver portfolio, designed specifically for low-power, high-reliability in-vehicle sub-networks with stringent EMC and functional safety requirements.

FAQ

What LIN protocol versions does the TJA1021T/20/C,118 support?

The TJA1021T/20/C,118 supports LIN 2.0, LIN 2.1, LIN 2.2, and LIN 2.2A, as well as ISO 17987-4:2016 (12 V) and SAE J2602. It is fully backward-compatible with earlier LIN revisions and certified for conformance testing per LIN 2.1 specification. This ensures interoperability across diverse automotive ECUs without protocol translation.

How does the TJA1021T/20/C,118 handle wake-up source identification?

The TJA1021T/20/C,118 signals wake-up source via TXD pin behavior in Standby mode: a weak pull-down indicates remote wake-up (LIN bus dominant), while a strong pull-down indicates local wake-up (WAKE_N edge). The microcontroller reads this state after entering Standby, then clears both flags by asserting SLP_N HIGH - a feature confirmed in the TJA1021T/20/C,118 datasheet Section 7.8.

Is the TJA1021T/20/C,118 pin-to-pin compatible with other NXP LIN transceivers?

Yes, the TJA1021T/20/C,118 is pin-to-pin compatible with the TJA1020 and MC33662(B) in both SO8 and HVSON8 packages. This allows drop-in replacement in existing designs, provided the target application requires 20 kBd operation and benefits from the integrated 30 kΩ termination resistor present in the TJA1021T/20/C,118 but not in the TJA1020.

What protection features does the TJA1021T/20/C,118 include for automotive environments?

The TJA1021T/20/C,118 includes ±6 kV HBM ESD protection on LIN, VBAT, and WAKE_N pins; ISO 7637-2 transient immunity; short-circuit protection on LIN to battery/ground; thermal shutdown at 175 °C typical; and VBAT undervoltage lockout at 4.4 V. These protections are validated per AEC-Q100 and documented in Sections 2.3 and 8 of the TJA1021T/20/C,118 datasheet.

Does the TJA1021T/20/C,118 require external components for basic LIN responder operation?

No - the TJA1021T/20/C,118 integrates a 30 kΩ termination resistor between LIN and VBAT, eliminating the need for an external resistor in responder applications. Only a 100 nF decoupling capacitor on VBAT and proper grounding of the HVSON8 exposed pad are required for standard operation, as specified in the TJA1021T/20/C,118 application schematic (Figure 7).