NXP Semiconductors MC33388D

Overview

MC33388D from NXP (formerly Freescale/Motorola) is an automotive fault-tolerant low-speed CAN physical layer transceiver in SO-14 package, supporting 10–125 kBaud operation, −40°C to +125°C ambient range, and dual-mode (differential/single-wire) bus recovery under failure. It serves as the interface between microcontroller UART/CAN peripheral and unshielded twisted-pair CAN bus in body electronics modules.

For engineers reviewing the MC33388D datasheet, MC33388D pinout, MC33388D application, or MC33388D equivalent, key selection considerations include its 15 µA sleep current, automatic bus-failure detection and mode-switching logic, VBAT-supplied wake-up capability, and integrated RTH/RTL switch control for external termination resistors.

Technical Context

The MC33388D implements a dual-path receiver architecture: differential comparator active during normal operation, with automatic fallback to single-ended CANH or CANL comparators upon wire interruption or short-circuit faults (e.g., CANH-to-battery or CANL-to-ground). Its transmitter uses high-side (CANH) and low-side (CANL) switches with internal slope control (3.5–10 V/µs) to minimize RFI on unshielded cabling.

Four operational modes-Normal, Receive Only, Standby VBAT, and Sleep-are controlled via STB and EN pins, with INH output enabling/disabling external 5V regulators. Fault detection includes eight defined wiring failures, each triggering specific internal switch actions (S1–S5), thermal shutdown at 165°C, and battery fail flag latching via NERR in Receive Only mode.

Key Specifications

Pinout & Package

MC33388D is housed in a plastic SO-14 narrow-body package (Case 751A-03), surface-mountable with 1.27 mm pitch, rated for 120°C/W junction-to-ambient thermal resistance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TJA1055T/3 and SN65HVD256, the MC33388D uniquely combines VBAT-supplied 15 µA sleep current, dual-edge wake-up pin, battery fail flag latching, and RTH/RTL-controlled external termination-making it the only option among the three qualified for automotive body electronics with full fault-aware power management.

Availability

MC33388D is available at Aetrix Electronics and suitable for door control modules, roof modules, seat control units, and trunk/liftgate modules requiring stable component supply across extended automotive temperature and voltage ranges.

Supply support for MC33388D 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, and IoT applications, with deep heritage in automotive networking IP dating back to Motorola's CAN innovations.

The MC33388D belongs to NXP's legacy automotive CAN transceiver portfolio, specifically engineered for fault-tolerant, low-power body electronics multiplexing-prioritizing bus resilience, wake-up flexibility, and seamless integration with 5V microcontrollers and external regulators.

FAQ

What is the minimum operating baud rate supported by the MC33388D?

The MC33388D supports a minimum baud rate of 10 kBaud, as confirmed in the device description and electrical characteristics section. This enables compatibility with legacy low-speed CAN networks used in cost-sensitive automotive body applications where higher speeds are unnecessary. The MC33388D maintains full fault detection and recovery functionality across the entire 10–125 kBaud range.

How does the MC33388D handle CAN bus wire interruption faults?

The MC33388D detects CANH or CANL wire interruption (Faults #1 and #2) using edge-count difference monitoring between CANH and CANL signals. Upon detection, it automatically switches to single-ended reception on the intact line while keeping the transmitter path disabled-allowing continued message reception without disrupting network communication. The MC33388D resumes full differential operation once both lines recover.

Can the MC33388D operate without a VDD supply?

Yes-the MC33388D can operate solely from VBAT in Sleep and Standby VBAT modes, drawing as little as 15 µA. In these modes, VDD is not required; the device monitors bus activity and WAKE pin transitions to initiate wake-up. Once awakened, it asserts INH to enable the external 5V regulator, restoring VDD. The MC33388D remains fully functional-including NERR flag reporting and wake-up detection-throughout VDD-absent operation.

What is the purpose of the RTH and RTL pins on the MC33388D?

The RTH and RTL pins on the MC33388D provide controlled switching of external termination resistors to CANH and CANL, respectively. During normal operation, they connect the resistors to establish proper bus biasing; during faults (e.g., CANH short-to-battery), the internal switches open to isolate faulty lines. This eliminates need for external FETs or discrete logic, simplifying design while preserving fault-aware termination-key to the MC33388D's autonomous bus recovery capability.

Does the MC33388D support wake-up from both rising and falling edges on the WAKE pin?

Yes-the MC33388D features dual-edge sensitive wake-up logic on the WAKE pin. At entry to Sleep or Standby VBAT mode, it samples the WAKE pin voltage and stores it as a reference; any transition to the opposite state (high-to-low or low-to-high) triggers wake-up. Thresholds are VBAT-referenced (0.44×VBAT and 0.57×VBAT), with 500 mV hysteresis. This behavior is explicitly documented in the Electrical Characteristics table and Pin Function Description for the MC33388D.