NXP Semiconductors MC908EY16ACFJER

Overview

MC908EY16ACFJER from Freescale Semiconductor is a 8-bit HCS08-core microcontroller with 16 KB on-chip FLASH, 512 B RAM, integrated ADC10 (10-bit, 8-channel), BEMF counter, ESCI, SPI, and dual timer modules (TIMA/TIMB). It operates from 2.7–5.5 V, supports internal/external clock sources up to 8 MHz, and targets motor control and industrial sensing applications.

For engineers reviewing the MC908EY16ACFJER datasheet, MC908EY16ACFJER pinout, MC908EY16ACFJER application, or MC908EY16ACFJER equivalent, key selection criteria include FLASH security byte validation ($FFF6–$FFFD), trimmed internal oscillator accuracy (±2% over –40°C to +125°C), 10-bit ADC sampling rate (up to 100 kSPS), BEMF counter for brushless DC motor commutation, and ESCI/SPI serial interface support.

Technical Context

The MC908EY16ACFJER implements the HCS08 CPU core with 16 MB linear address space, 24-bit stack pointer, and 8-level hardware interrupt priority. Its Internal Clock Generator (ICG) integrates a digitally controlled oscillator (DCO), modulo-N divider, frequency comparator, and digital loop filter for adaptive clock trimming.

Security enforcement occurs during monitor mode entry: host must supply eight matching bytes at $FFF6–$FFFD; entry is denied if ≥5 of those bytes are $00. The BEMF counter module accepts differential back-EMF inputs and provides edge-triggered capture for precise rotor position detection in BLDC motor drives.

Key Specifications

Pinout & Package

MC908EY16ACFJER is housed in a 44-pin QFP (Quad Flat Package) with 0.8 mm pitch, JEDEC MS-026 compliant, body size 10 × 10 mm, and exposed thermal pad for enhanced heat dissipation in motor drive applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908EY16ACFJER, MC908EY8ACFJER offers identical functionality at lower memory cost, while S9KEAZ128AMLH provides modern ARM architecture and expanded peripherals at the expense of BEMF hardware acceleration and legacy toolchain compatibility.

Availability

MC908EY16ACFJER is available at Aetrix Electronics and suitable for brushless DC motor control, industrial sensor nodes, automotive cabin fans, and smart power outlets requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MC908EY16ACFJER 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) designed high-reliability microcontrollers for automotive, industrial, and appliance markets with emphasis on robust analog integration and real-time control.

The MC68HC908EY16A family was engineered specifically for cost-sensitive, high-volume motor control applications requiring deterministic timing, analog signal conditioning, and secure firmware update capability - exemplified by the MC908EY16ACFJER variant.

FAQ

What is the maximum operating frequency of the MC908EY16ACFJER internal oscillator?

The MC908EY16ACFJER internal oscillator, implemented as a digitally controlled oscillator (DCO) within the ICG module, achieves a maximum frequency of 8 MHz across the full operating temperature and voltage range. Factory-trimmed and user-adjustable calibration ensures ±2% accuracy without external components, making it suitable for timing-critical motor control loops where crystal-free operation is preferred.

How does the FLASH security feature work on the MC908EY16ACFJER?

The MC908EY16ACFJER enforces FLASH security during monitor mode entry: the host must transmit eight bytes matching the user-programmed values stored at memory locations $FFF6–$FFFD. If five or more of those bytes are $00, monitor mode entry is denied. This prevents unauthorized firmware extraction while allowing legitimate debug access when valid security bytes are programmed - a requirement explicitly stated in the datasheet addendum.

Which pins on the MC908EY16ACFJER support the BEMF counter function?

The MC908EY16ACFJER dedicates PTB7/AD7 and PTB6/AD6 as TBCH1 and TBCH0 - the two input terminals for the BEMF counter module. These pins accept differential back-EMF signals from motor windings and support edge-triggered capture with hardware timestamping, enabling precise rotor position detection without CPU polling or timer resource consumption.

Does the MC908EY16ACFJER support both 3.3 V and 5 V operation?

Yes, the MC908EY16ACFJER operates across a wide supply range of 2.7 V to 5.5 V, making it compatible with both 3.3 V and 5 V system rails. Its I/O pins are 5 V tolerant when configured as inputs, and its internal voltage regulator maintains stable core operation regardless of VDD level - simplifying design in mixed-voltage environments such as industrial PLCs interfacing with legacy 5 V sensors and modern 3.3 V communication ICs.

What peripheral modules are included in the MC908EY16ACFJER for motor control applications?

The MC908EY16ACFJER integrates several motor-control-optimized peripherals: the BEMF Counter Module for rotor position sensing, dual timer modules (TIMA and TIMB) supporting complementary PWM generation with dead-time insertion, ADC10 for current/voltage feedback sampling, ESCI for UART-based host communication, and SPI for daisy-chained gate drivers or position encoders - all coordinated by the HCS08 CPU with deterministic interrupt latency critical for real-time commutation.