NXP Semiconductors MC68HC11A1MFNE

Overview

MC68HC11A1MFNE from Freescale Semiconductor is an 8-bit HCMOS single-chip microcontroller featuring 512 bytes of on-chip RAM, 2 KB of EEPROM, and 12 KB of ROM. It integrates a 16-bit programmable timer, 8-channel 8-bit ADC, dual serial interfaces (SCI and SPI), and five parallel I/O ports. It is used in industrial control systems requiring deterministic real-time response and nonvolatile configuration storage.

For engineers reviewing the MC68HC11A1MFNE datasheet, MC68HC11A1MFNE pinout, MC68HC11A1MFNE application, or MC68HC11A1MFNE equivalent, this page delivers verified electrical specs, validated pin functions, confirmed operating modes (single-chip, expanded, bootstrap), and documented alternative parts for legacy design continuity and supply chain resilience.

Technical Context

The MC68HC11A1MFNE implements the M68HC11 CPU core with full instruction set compatibility to the Motorola 6800 family. It operates in three primary modes: single-chip (all memory and I/O internal), expanded multiplexed (external memory interface via AD0–AD7 and A8–A13), and special bootstrap (on-chip monitor ROM execution for in-system programming).

Its peripheral subsystem includes a 16-bit timer with input capture/output compare, real-time interrupt (RTI) with programmable rate, pulse accumulator, and dual serial interfaces - SCI supporting asynchronous full-duplex communication and SPI supporting master/slave synchronous transfers. The 8-channel ADC supports single- and multiple-channel conversion with configurable sample timing.

Key Specifications

Pinout & Package

MC68HC11A1MFNE is housed in a 48-pin DIP (dual in-line package) with 0.6-inch body width, compliant with JEDEC MS-001. Pin functions are validated per Freescale's MC68HC11A8 Technical Data document (which applies identically to A1 variant per Family Summary Table 1-1 and Ordering Information Table B-1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68HC11A1MFNE, MC68HC11E9CP offers extended serial timing and packaging flexibility but identical memory architecture, while MC912B32CFUE provides modern FLASH-based reprogrammability and CAN, at the cost of migration effort and higher component cost.

Availability

MC68HC11A1MFNE is available at Aetrix Electronics and suitable for industrial motor control, automotive body electronics, medical infusion devices, and building HVAC sensor nodes requiring stable component supply and long-term obsolescence management.

Supply support for MC68HC11A1MFNE 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) is a fabless semiconductor company specializing in microcontrollers, analog, and mixed-signal ICs for automotive, industrial, and consumer markets.

The MC68HC11 family was designed for cost-sensitive, real-time embedded control applications where deterministic timing, on-chip nonvolatile storage, and minimal external components were critical - especially in legacy industrial and automotive ECUs.

FAQ

What is the maximum operating frequency of the MC68HC11A1MFNE?

The MC68HC11A1MFNE operates with a maximum E clock frequency of 2 MHz, derived from an external crystal or oscillator connected to XTAL/EXTAL pins. This corresponds to a maximum oscillator frequency of 4 MHz. The CPU executes instructions at rates dependent on addressing mode and instruction type, with typical throughput ranging from 0.5 to 2 million instructions per second.

Does the MC68HC11A1MFNE include a hardware watchdog timer?

Yes, the MC68HC11A1MFNE includes a Computer Operating Properly (COP) watchdog timer. Its timeout period is configurable via the OPTION register and ranges from approximately 2.5 ms to 1.6 seconds, depending on selected prescaler values (CR1/CR0 bits). The COP must be periodically cleared by software to prevent system reset.

Can the MC68HC11A1MFNE execute code from its internal EEPROM?

No, the MC68HC11A1MFNE cannot execute code directly from EEPROM. Its 2 KB EEPROM is intended for data storage only - such as calibration constants, configuration parameters, or fault logs. Program execution occurs from ROM (12 KB) or external memory in expanded mode; EEPROM contents must be copied to RAM for runtime use.

What are the supported operating modes of the MC68HC11A1MFNE?

The MC68HC11A1MFNE supports three primary operating modes: single-chip mode (all memory and I/O internal), expanded multiplexed mode (external memory interface using AD0–AD7 and A8–A13), and special bootstrap mode (execution from on-chip monitor ROM for in-system programming and debugging). Mode selection is controlled by MODA and MODB pins at reset.

Is the MC68HC11A1MFNE pin-compatible with other MC68HC11 variants like the A8 or E9?

No, the MC68HC11A1MFNE (48-pin DIP) is not pin-compatible with the MC68HC11A8 (48-pin DIP, same package) or MC68HC11E9CP (52-pin PLCC). While the A1 and A8 share identical pinouts and electrical specifications per Freescale's family documentation, the E9 uses a different package and adds pins for enhanced peripherals - requiring PCB layout changes for substitution.