NXP Semiconductors MC33389CDWR2

Overview

MC33389CDWR2 from NXP (formerly Freescale) is a System Basis Chip (SBC) integrating dual 5 V low-dropout regulators (100 mA and 200 mA), a low-speed fault-tolerant CAN transceiver (125 kBaud), SPI interface, programmable watchdog, and VBAT-switched 10 Ω high-side driver (V3) for automotive engine control units. It supports Normal/Stand-by/Sleep modes with <125 µA sleep current and operates across -40°C to 125°C.

For engineers reviewing the MC33389CDWR2 datasheet, MC33389CDWR2 pinout, MC33389CDWR2 application, or MC33389CDWR2 equivalent, key selection criteria include its dual-regulator power architecture, LS-CAN fault tolerance per ISO 11898-3, SPI-controlled wake-up inputs (L0–L2), VBAT monitoring with BATFAIL detection, and integrated thermal protection for V1/V2/V3.

Technical Context

The MC33389CDWR2 implements a monolithic automotive SBC architecture with three independent voltage domains: V1 (microcontroller supply, 5.0 V ±3%, 100 mA), V2 (peripheral supply, 5.0 V ±5%, 200 mA), and V3 (VBAT-switched 10 Ω high-side output). Its CAN transceiver complies with ISO 11898-3 for low-speed fault-tolerant operation up to 125 kBaud and includes bus failure detection (short-to-battery, short-to-ground, open-wire) with dedicated thresholds for CANH/CANL.

Control is executed via a 4-wire SPI interface (CS, SCLK, MOSI, MISO) supporting register read/write, interrupt reporting (INT), reset assertion (RST), and programmable cyclic wake-up timing (8 selectable intervals from 22.4 ms to 8.2 s). Mode transitions (Normal/Stand-by/Sleep) are decoupled from CAN interface states and managed through SPI commands and external wake-up sources including CAN bus activity, L0–L2 inputs, and VBAT level thresholds.

Key Specifications

Pinout & Package

MC33389CDWR2 uses a 28-pin SOICW (SO-28) package with exposed thermal pad, Pb-free (EG suffix), rated for -40°C to 125°C ambient. Pin 17 is NC (no connect); all GND pins (6–9, 20–23) are internally tied to lead frame for thermal conduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar System Basis Chip applications.

Compared with MC33389CDWR2, MC33883DWR2 omits V3 switching capability and offers less granular wake-up control, while TLF35584QVVS1 adds safety features but increases system complexity and cost due to external CAN PHY requirement.

Availability

MC33389CDWR2 is available at Aetrix Electronics and suitable for automotive engine control units, body control modules, and transmission control units requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MC33389CDWR2 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 leader in automotive semiconductors, delivering secure, reliable, and energy-efficient solutions for vehicle electrification, connectivity, and autonomy.

The MC33389 product line was designed specifically for automotive body electronics and powertrain ECUs, integrating power management, communication, and system supervision into a single chip to reduce design complexity and improve robustness.

FAQ

What is the maximum transient voltage rating for MC33389CDWR2 on the VBAT pin?

The MC33389CDWR2 supports up to 40 V transient voltage on the VBAT pin for durations ≤500 ms, complying with automotive load dump requirements per ISO 7637-2 Pulse 5a. This rating applies under specified thermal conditions and ensures continued operation without latch-up or permanent damage when used with appropriate input filtering.

Does MC33389CDWR2 support both Normal and Sleep modes simultaneously with CAN bus activity?

No. MC33389CDWR2 decouples CAN interface operation from system mode states: CAN remains active in Stand-by mode but is disabled in Sleep mode. In Sleep mode, the CAN transceiver is powered down to minimize current; wake-up requires external event (CAN bus activity in Stand-by, L0–L2 edge, or VBAT threshold crossing) to transition back to Stand-by or Normal mode before CAN resumes.

What is the function of the RTH and RTL pins on MC33389CDWR2?

The RTH and RTL pins on MC33389CDWR2 provide dedicated connection points for external 120 Ω termination resistors between CANH and ground (RTH) and between CANL and ground (RTL). They are not internal resistors but routing terminals-ensuring proper LS-CAN bus impedance matching per ISO 11898-3 and enabling flexible PCB layout for termination placement.

How does the V3 output of MC33389CDWR2 behave under short-circuit conditions?

Under short-circuit, the V3 output of MC33389CDWR2 activates current limiting and thermal foldback: output current is clamped near 150 mA (typical), and junction temperature rise triggers shutdown at 155–185°C. Recovery occurs automatically after cooling below hysteresis threshold. This protects external relays and wiring without requiring fuse replacement or manual reset.

Can MC33389CDWR2 be used in systems requiring ASIL compliance?

MC33389CDWR2 is not certified to any ASIL level. It lacks hardware-level fault collection, diagnostic coverage reporting, and safety mechanisms required for ISO 26262 compliance. For ASIL-B or higher applications, designers must select purpose-built safety chips such as NXP's TLF35584 or S32K series with documented FMEDA and safety manuals.