NXP Semiconductors MC33287DW

Overview

MC33287DW from Freescale Semiconductor is an automotive-grade contact monitoring and dual low-side protected driver IC. It interfaces switch contacts (to VBAT or GND) with a microcontroller, featuring eight 40 V-rated sense inputs with ratiometric thresholds, two current-limited (535 mA) low-side drivers with 50 V internal overvoltage clamping and independent overtemperature shutdown, and diagnostic reporting via multiplexed and dedicated outputs. It is used in vehicle body control modules for switch status acquisition and load driving.

For engineers reviewing the MC33287DW datasheet, MC33287DW pinout, MC33287DW application, or MC33287DW equivalent, key selection considerations include its 20-pin SOICW package, -40°C to +125°C operating range, 55 µA standby current, dual-driver fault detection logic, and compatibility with 5 V microcontroller I/O levels.

Technical Context

The MC33287DW integrates eight high-voltage sense inputs with programmable multiplexing via AD0–AD2 address pins, enabling single MCU ADC channel monitoring of up to seven inputs plus diagnostics. Its two low-side drivers feature complementary command polarity: CD1 is active-low while CD2 is active-high, each with independent thermal shutdown and voltage-based fault detection (VFAULT = 2.0–3.5 V).

Internal protection includes 50 V positive output clamp on OUTD1/OUTD2, RDS(ON) ≤ 3.20 Ω (typical 1.40 Ω), and dynamic timing parameters such as tON = 1.3 µs (typ), tOFF = 2.1 µs (typ), and edge rates under 10 µs. All sense inputs tolerate 40 V with ≥25 kΩ series resistance and exhibit 5–10 V hysteresis depending on VDD1.

Key Specifications

Pinout & Package

The MC33287DW is housed in a 20-pin SOICW (Small Outline Integrated Circuit, Wide-body) package with 0.600-inch body width and standard 1.27 mm pitch. Pin 1 is marked by a notch or dot; the package is RoHS-compliant (Pb-free, EG suffix variant available).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar contact monitoring and dual low-side driver applications.

Compared with MC33287DW, MC33883 offers fewer sense channels and no multiplexed diagnostics, while BTS724G provides higher drive current but no built-in monitoring - making MC33287DW uniquely suited for cost-sensitive, space-constrained BCM designs requiring integrated sensing and dual low-side drive.

Availability

MC33287DW is available at Aetrix Electronics and suitable for automotive body control modules, door modules, seat control units, and roof modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MC33287DW 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

Freescale Semiconductor (now part of NXP Semiconductors) was a leading designer of automotive and industrial analog/mixed-signal ICs, known for robust, AEC-Q100-qualified products targeting harsh-environment applications.

The MC33287DW belongs to Freescale's automotive analog interface product line, engineered specifically for contact monitoring and protected low-side driving in body electronics - balancing integration, protection, and diagnostic capability for cost-effective ECU designs.

FAQ

What is the maximum input voltage rating for the sense inputs on the MC33287DW?

The MC33287DW sense inputs (IN0–IN7) are rated for up to 40 V continuous input voltage, provided a minimum series resistor of 25 kΩ is used. This rating allows direct interfacing with automotive battery rails and supports operation during load dump events per ISO 7637-2. The input clamp voltage is specified at 17–23 V (at 100 µA), with internal protection sustaining up to 40 V without damage.

How does the MC33287DW handle fault detection for its low-side drivers?

The MC33287DW implements independent fault detection for each low-side driver (OUTD1 and OUTD2) using voltage threshold comparison. When a fault occurs - such as open load, short-to-GND, or overload - the corresponding DIAGD1 or DIAGD2 pin asserts a logic-level signal. These diagnostic outputs can be routed directly to MCU GPIOs or multiplexed into OUT1 via AD0–AD2 for ADC-based reading. Fault detection triggers at VFAULT = 2.0–3.5 V and includes unfiltered, real-time reporting.

Can the MC33287DW operate with a 5 V microcontroller supply (VDD2) while interfacing with a 12 V battery rail?

Yes, the MC33287DW is designed for exactly this configuration: VDD2 accepts 4.75–5.25 V (standard 5 V logic supply), while VDD1 handles 7.0–18 V (battery rail). Input thresholds (e.g., CD1/CD2, AD0–AD2) are referenced to VDD2, ensuring full compatibility with 5 V MCU I/O. Sense inputs remain referenced to VDD1, enabling accurate ratiometric measurement across battery voltage variations - a core requirement for automotive applications.

What is the purpose of the AD0–AD2 pins on the MC33287DW?

The AD0–AD2 pins on the MC33287DW configure the internal 8-to-1 analog multiplexer that routes signals to the OUT1 output pin. By setting these three address bits, the user selects which of IN0–IN6 or DIAGD1/DIAGD2 appears at OUT1 as a 0–6.0 V analog voltage. This enables a single MCU ADC channel to monitor up to seven switch inputs or two diagnostic flags, significantly reducing pin count and external component requirements in resource-constrained ECUs.

Does the MC33287DW support Pb-free (RoHS-compliant) packaging?

Yes, the MC33287DW is available in Pb-free packaging, designated by the EG suffix (e.g., MCZ33287EG/R2). The DW suffix variant (MC33287DW/R2) is also RoHS-compliant and meets JEDEC J-STD-020C reflow standards. Both variants share identical electrical specifications, thermal performance, and pinout - the EG version simply replaces leaded solder with lead-free terminations, maintaining full drop-in compatibility in assembly processes.