NXP Semiconductors MC68HC11F1CFN4

Overview

MC68HC11F1CFN4 from Freescale Semiconductor is an 8-bit microcontroller unit (MCU) featuring 2 KB of on-chip EEPROM, 192 bytes of RAM, and integrated peripherals including a 10-bit ADC, two serial interfaces (SCI and SPI), and a 16-bit timer system with input capture/output compare. It operates at up to 3.2 MHz in single-chip mode and targets embedded control applications such as automotive body electronics and industrial sensor nodes.

For engineers reviewing the MC68HC11F1CFN4 datasheet, MC68HC11F1CFN4 pinout, MC68HC11F1CFN4 application, or MC68HC11F1CFN4 equivalent, key selection considerations include its 68-pin PLCC package, EEPROM endurance (10,000 write/erase cycles), COP watchdog, and support for WAIT/STOP low-power modes - all critical for legacy automotive and industrial firmware maintenance.

Technical Context

The MC68HC11F1CFN4 implements the classic HC11 CPU core with full instruction set compatibility to the M6800 family, supporting six addressing modes and a 16-bit program counter. Its memory architecture includes fixed-function on-chip ROM bootloader, user-programmable EEPROM mapped into the $E000–$FFFF address space, and configurable chip selects for external memory expansion.

Peripherals are tightly coupled to the internal bus: the 10-bit ADC supports eight analog inputs with software- or timer-triggered conversions; the SCI provides asynchronous full-duplex communication with programmable baud rates; and the SPI operates in master/slave mode with independent clock polarity and phase control - all accessible via dedicated I/O ports A–G with configurable direction registers.

Key Specifications

Pinout & Package

MC68HC11F1CFN4 is housed in a 68-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead configuration, lead pitch of 0.05 inch (1.27 mm), and body size 1.100 inch × 1.100 inch (27.94 mm × 27.94 mm). Pin assignments follow Freescale's standard HC11 PLCC layout per Figure 2-1 in the technical data manual.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with MC68HC11A8CP and MC9S12DP512CPUE, the MC68HC11F1CFN4 uniquely balances legacy compatibility, EEPROM-based field update capability, and minimal external component count - making it the only viable choice for maintaining or extending existing HC11-based systems without architectural overhaul.

Availability

MC68HC11F1CFN4 is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor nodes, appliance motor control, and legacy industrial HMI applications requiring stable component supply and long-term lifecycle support.

Supply support for MC68HC11F1CFN4 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 embedded processors and analog/mixed-signal ICs, founded in 2004 as a spin-off from Motorola.

The MC68HC11F1CFN4 belongs to the HC11 family - a line of 8-bit microcontrollers developed for cost-sensitive, real-time embedded control in automotive, industrial, and appliance markets where reliability and code compatibility were paramount.

FAQ

What is the maximum operating frequency of the MC68HC11F1CFN4?

The MC68HC11F1CFN4 supports a maximum E-clock frequency of 3.2 MHz in single-chip mode. This corresponds to a 6.4 MHz crystal or external oscillator input, as the on-chip oscillator divides the input by two to generate the E-clock. Timing-critical applications must observe setup/hold requirements relative to this E-clock, especially for external memory accesses and peripheral register writes.

Does the MC68HC11F1CFN4 support in-system programming of its EEPROM?

Yes, the MC68HC11F1CFN4 supports in-system programming of its 2 KB on-chip EEPROM using a documented command sequence executed from RAM. No external high-voltage programmer is needed. The process requires disabling interrupts, setting specific values in the CONFIG and PPROG registers, and issuing timed write pulses - all detailed in Section 4.4.1 of the Freescale technical data manual for MC68HC11F1CFN4.

What package type is used for the MC68HC11F1CFN4?

The MC68HC11F1CFN4 uses a 68-pin Plastic Leaded Chip Carrier (PLCC) package with J-leads and a 1.100 inch × 1.100 inch body. The "FN" suffix in the part number explicitly denotes this PLCC variant, distinguishing it from the 80-pin QFP version (MC68HC11F1CFU4). Pin assignments match Freescale's standard HC11 PLCC layout shown in Figure 2-1 of the datasheet.

Can the MC68HC11F1CFN4 operate in low-power modes?

Yes, the MC68HC11F1CFN4 supports two low-power modes: WAIT and STOP. In WAIT mode, the CPU halts but peripherals remain active and can wake the device via interrupt. In STOP mode, all clocks stop and current drops to under 10 µA; wake-up is possible only via RESET, IRQ, or XIRQ. Both modes are entered via SWI or STOP instructions and require proper configuration of the CCR register before execution.

What is the role of the built-in COP watchdog timer in the MC68HC11F1CFN4?

The Computer Operating Properly (COP) watchdog timer in the MC68HC11F1CFN4 monitors software execution integrity by requiring periodic service (a write to the COPCTL register) within a configurable timeout window (0.5 ms to 1.0 s). If unserviced, it forces a hardware reset - preventing runaway code or lockup in safety-critical embedded systems like automotive body controllers where the MC68HC11F1CFN4 is commonly deployed.