NXP Semiconductors MC68331CFC16

Overview

MC68331CFC16 from Freescale Semiconductor is a 32-bit modular microcontroller featuring the CPU32 core, System Integration Module (SIM), General-Purpose Timer (GPT), and Queued Serial Module (QSM). It operates at 16 MHz with a 132-pin PQFP package, −40 to +85 °C temperature range, and supports external bus interfacing, PWM, input capture, SCI, and QSPI. It is used in industrial motor control and embedded automation systems requiring deterministic real-time response.

For engineers reviewing the MC68331CFC16 datasheet, MC68331CFC16 pinout, MC68331CFC16 application, or MC68331CFC16 equivalent, key selection considerations include its static CPU32 architecture, integrated watchdog and clock monitor, 16-bit GPT with five output compare channels, QSM dual-protocol serial support, and 132-pin PQFP mechanical compatibility with legacy 68K-based control designs.

Technical Context

The MC68331CFC16 implements a modular intermodule bus (IMB) architecture with standardized 24-bit address and 16-bit data paths, enabling deterministic communication between CPU32, SIM, GPT, and QSM. Its SIM provides programmable chip selects (CS0–CS10), periodic interrupt generation, and system protection logic including bus, HALT, and software watchdog monitors.

CPU32 executes instructions in fully static mode with loop execution, table lookup/interpolate, and trace-on-change-of-flow capabilities. The GPT includes two 16-bit free-running counters, three input capture channels, four output compare channels, one combined input capture/output compare channel, pulse accumulator, and two PWM outputs - all synchronized to an optional external PCLK.

Key Specifications

Pinout & Package

MC68331CFC16 uses a 132-pin PQFP package (JEDEC MS-026AC) with 0.65 mm lead pitch, 20.0 × 20.0 mm body size, and standard thermal pad layout. Pin functions are defined per Freescale MC68331TS/D Rev. 2, Figure 2.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 32-bit industrial microcontroller applications.

Compared with MC68331CFC16, MC68332CAG16 offers greater on-chip memory and enhanced serial throughput but mandates mechanical redesign, while MC9328MX1CZK delivers higher compute throughput and OS readiness at the expense of cycle-accurate timing control and legacy 68K ecosystem compatibility.

Availability

MC68331CFC16 is available at Aetrix Electronics and suitable for industrial motor control, factory automation PLCs, railway signaling interfaces, and energy metering gateways requiring stable component supply across extended product lifecycles.

Supply support for MC68331CFC16 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) specialized in high-reliability microcontrollers for automotive, industrial, and aerospace applications before its 2015 acquisition.

The MC68331CFC16 belongs to the 683xx modular microcontroller family, designed specifically for deterministic real-time control in harsh environments - emphasizing hardware-based timing, system-level fault coverage, and long-term industrial qualification.

FAQ

What is the maximum operating frequency of the MC68331CFC16?

The MC68331CFC16 is rated for guaranteed operation at 16 MHz across its specified industrial temperature range of −40 to +85 °C. Its fully static CPU32 core permits clock stopping without data loss, and system timing remains valid down to DC - enabling ultra-low-power modes where the clock is gated during idle intervals. The MC68331CFC16 does not support overclocking beyond 16 MHz under specification.

Does the MC68331CFC16 include on-chip flash or RAM?

No, the MC68331CFC16 contains no on-chip nonvolatile memory or RAM. It relies entirely on external memory mapped via its 24-bit address bus and 16-bit data bus. Code execution occurs from external EPROM, Flash, or SRAM devices selected through its eleven programmable chip-select outputs. This architecture prioritizes flexibility and upgradeability over integrated storage.

How many interrupt request inputs does the MC68331CFC16 support?

The MC68331CFC16 provides seven dedicated vectored interrupt request inputs labeled IRQ1 through IRQ7 on Port F pins PF1–PF7. These inputs support priority-based nesting and automatic vector generation. In addition, the CPU32 core supports exception vectors for reset, bus error, address error, and trace exceptions - all handled independently of the IRQ lines.

Can the MC68331CFC16 generate PWM signals?

Yes, the MC68331CFC16's General-Purpose Timer (GPT) module includes two dedicated PWM output channels: PWMA and PWMB. These are hardware-generated, independent of CPU intervention, and support adjustable duty cycle and period via GPT registers. They are routed to dedicated pins PCLK, PWMA, and PWMB - enabling precise motor gate drive or LED dimming without software overhead.

Is the MC68331CFC16 pin-compatible with other 683xx family members?

No, the MC68331CFC16 is not pin-compatible with other 683xx variants such as the MC68332 or MC68376. While sharing the same CPU32 core and modular architecture, differences in peripheral integration - particularly the absence of on-chip RAM in MC68331CFC16 and distinct QSM register mapping - result in incompatible pin assignments and signal routing. Board-level replacement requires schematic and layout revision.