NXP Semiconductors MC908AZ32ACFUE

Overview

MC908AZ32ACFUE from NXP (formerly Freescale) is an 8-bit HCS08 microcontroller featuring 32 KB on-chip Flash memory, 1 KB RAM, and integrated CAN 2.0A/B controller. It operates at up to 40 MHz bus speed with internal PLL clock generation, supports 15-channel 10-bit ADC, and includes SCI, SPI, two timer modules (TIMA/TIMB), and COP watchdog. It targets automotive body control modules requiring robust real-time I/O and CAN communication.

For engineers reviewing the MC908AZ32ACFUE datasheet, MC908AZ32ACFUE pinout, MC908AZ32ACFUE application, or MC908AZ32ACFUE equivalent, key selection criteria include its 48-pin QFP package, CAN interface compliance, Flash endurance (100K erase/write cycles), operating voltage range (2.7–5.5 V), and qualification for automotive temperature grade (–40°C to +125°C).

Technical Context

The MC908AZ32ACFUE implements the HCS08 CPU core with enhanced addressing modes and a 16-bit index register. Its System Integration Module (SIM) manages reset sources-including LVI, COP timeout, and external RST-and coordinates low-power modes (WAIT/STOP) with wake-up via IRQ, SCI, or timer events.

The Clock Generator Module (CGM) integrates a crystal oscillator, PLL with programmable multiplication factor (×1 to ×32), and base clock selector supporting multiple clock sources. The MSCAN08 controller provides full CAN 2.0A/B protocol handling with three message buffers and flexible filter masking.

Key Specifications

Pinout & Package

MC908AZ32ACFUE is housed in a 48-pin Quad Flat Package (QFP) with 0.5 mm pitch, thermally enhanced for automotive environments. Pin assignments follow standard HCS08 port mapping with dedicated CAN Tx/Rx, ADC analog supply/ground, and CGM filter capacitor connections.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC9S08DZ32F2CLK, MC908AZ32ACFUE offers integrated keyboard scanning and retains full CAN functionality without peripheral trade-offs; versus S9KEAZ32AMLH, it delivers deterministic real-time response and lower power consumption in CAN-centric automotive control tasks.

Availability

MC908AZ32ACFUE is available at Aetrix Electronics and suitable for automotive body electronics, industrial CAN nodes, smart HVAC actuators, and diagnostic interface designs requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant operation.

Supply support for MC908AZ32ACFUE 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 secure connectivity solutions for automotive, industrial, and IoT applications.

The MC908AZ32ACFUE belongs to the HCS08 microcontroller family, designed specifically for cost-sensitive, real-time automotive body electronics and industrial control applications requiring CAN, ADC, and robust flash-based firmware execution.

FAQ

What is the maximum bus frequency supported by the MC908AZ32ACFUE?

The MC908AZ32ACFUE supports a maximum bus frequency of 40 MHz, achieved using the internal PLL with programmable multiplication factor (×1 to ×32) and external crystal (1–8 MHz). This frequency governs instruction execution speed, peripheral timing, and CAN bit rate accuracy. The PLL lock time and stability depend on the external CGMXFC filter capacitor value, as specified in Chapter 8 of the MC908AZ32ACFUE datasheet.

Does the MC908AZ32ACFUE include hardware support for EEPROM emulation?

Yes, the MC908AZ32ACFUE includes dedicated EEPROM emulation features via its on-chip Flash memory and EEPROM control registers (EECTL, EEAR, etc.). It provides 2 KB of emulated EEPROM with 100K write/erase cycles, configurable sector sizes, and automatic wear leveling through firmware libraries. This eliminates the need for external EEPROM in applications storing calibration data or user settings.

Can the MC908AZ32ACFUE operate without an external crystal?

Yes, the MC908AZ32ACFUE can operate using its internal oscillator (ICS) in conjunction with the PLL for clock generation, eliminating the need for an external crystal in cost-sensitive or space-constrained designs. However, crystal-based operation is required for CAN timing compliance and applications demanding higher frequency accuracy (<±1%). The internal oscillator drift exceeds CAN bit timing tolerance above 125 kbps.

What debug interfaces are supported by the MC908AZ32ACFUE?

The MC908AZ32ACFUE supports background debug mode (BDM) via a single-wire interface using the BKGD pin, enabling full read/write memory access, breakpoint setting, and real-time register inspection. It does not support JTAG. The built-in Monitor ROM also allows UART-based firmware updates without debug hardware, using standard SCI pins and predefined command protocols.

Is the MC908AZ32ACFUE pin-compatible with other HCS08 family members?

No, the MC908AZ32ACFUE is not pin-compatible with most other HCS08 devices due to its unique 48-pin QFP layout optimized for CAN, ADC, and expanded I/O. While it shares functional port naming (e.g., PTA, PTB) and register-level compatibility with the broader HCS08 family, mechanical pin mapping differs significantly from 44-pin or 64-pin variants like MC9S08DZ128 or MC9S08GB60. PCB layout must be designed specifically for MC908AZ32ACFUE.