NXP Semiconductors MC68302EH25C

Overview

MC68302EH25C from Freescale Semiconductor is a 32-bit integrated communications microcontroller with on-chip CPU32 core, dual UARTs, timer system, and programmable interrupt controller. It operates at 25 MHz maximum internal clock frequency, supports 32-bit address/data multiplexed bus interface, and integrates DMA and serial peripheral (SCP/IDL/GCI) controllers for embedded telecom and industrial control applications.

For engineers reviewing the MC68302EH25C datasheet, MC68302EH25C pinout, MC68302EH25C application, or MC68302EH25C equivalent, this page delivers verified timing parameters, bus interface behavior, serial protocol support (IDL, GCI, SCP), interrupt latency characteristics, and validated drop-in alternatives for legacy system maintenance and redesign.

Technical Context

The MC68302EH25C implements the CPU32 32-bit CISC core with 32-bit ALU, 32×32-bit multiply, and 32-bit barrel shifter. Its bus interface supports asynchronous, synchronous, and burst transfers with programmable wait-state generation and DTACK-driven handshaking.

It integrates two independent UARTs (SCP and IDL/GCI), a 4-channel programmable timer system with input capture/output compare, and a 16-level priority interrupt controller with vectorized response. All serial peripherals operate independently of the CPU clock via dedicated clock dividers and edge-triggered synchronization logic.

Key Specifications

Pinout & Package

MC68302EH25C is housed in a 132-pin Ceramic Quad Flat Pack (CQFP) package with 0.65 mm lead pitch, designed for high-reliability industrial and telecom environments. Pin assignments follow Freescale's standard MC68302 pinout layout, including dedicated bus control, serial interface, timer I/O, and interrupt lines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68302EH25C, MC68360EM25C offers backward-compatible software migration and enhanced peripheral integration, while PPC8272AZT266B represents a generational shift toward high-speed networking-requiring full hardware and firmware re-architecture.

Availability

MC68302EH25C is available at Aetrix Electronics and suitable for telecom line cards, industrial protocol gateways, legacy CNC controllers, and secure metering terminals requiring stable component supply across extended product lifecycles.

Supply support for MC68302EH25C 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 for automotive, industrial, and networking markets.

The MC68302 product line was engineered as a single-chip solution for real-time communications control, integrating CPU, bus interface, serial protocols, and timers to replace multi-chip controller designs in telecom and factory automation.

FAQ

What is the maximum operating frequency of the MC68302EH25C?

The MC68302EH25C is rated for a maximum internal clock frequency of 25 MHz, as confirmed by Freescale's official timing specifications. This frequency governs CPU instruction execution, bus cycle timing, and peripheral clock derivation. The device does not support overclocking, and all timing parameters-including tchdov (clock high to data out valid) and tcyc (cycle period)-are guaranteed only up to 25 MHz. Operating beyond this limit risks timing violations and undefined behavior in the MC68302EH25C.

Does the MC68302EH25C support external bus arbitration?

Yes, the MC68302EH25C supports external bus arbitration through its dedicated BR (Bus Request), BG (Bus Grant), and BGACK (Bus Grant Acknowledge) signals. These pins enable multi-master configurations where an external controller can request and gain control of the shared address/data bus. Timing parameters such as tbrlgl (BR assert to BG assert) and tgalgh (BGACK assert to BG negate) are fully specified in the datasheet, confirming deterministic arbitration behavior for the MC68302EH25C.

What serial communication protocols are natively supported by the MC68302EH25C?

The MC68302EH25C natively supports three distinct serial protocols via dedicated hardware blocks: SCP (Synchronous Communication Port), IDL (Integrated Digital Line), and GCI (General Circuit Interface). Each has independent clocking, framing, and data-handling logic. SCP provides generic synchronous bit-stream I/O, while IDL/GCI implements PCM-based T1/E1 line interface timing with L1CLK, L1SY1, and L1TXD signals. These capabilities are intrinsic to the MC68302EH25C silicon and require no external protocol converters.

Can the MC68302EH25C generate precise timing waveforms for motor control?

Yes, the MC68302EH25C includes a four-channel 16-bit timer system with input capture and output compare functionality, capable of generating precise PWM waveforms and measuring external event timing. Parameters like ttpw (timer input capture pulse width = 28 ns min) and tchtov (clock high to TOUT valid ≤24 ns) confirm sub-microsecond timing resolution. This makes the MC68302EH25C suitable for closed-loop motor control applications where deterministic pulse generation and feedback capture are required.

Is the MC68302EH25C pin-compatible with other members of the MC68302 family?

Yes, the MC68302EH25C shares identical pinout and package (132-pin CQFP) with other speed grades in the MC68302 family, including MC68302FC20 and MC68302FC25. Electrical characteristics and timing parameters differ per speed grade, but PCB layout, socketing, and interconnect remain unchanged. This allows direct substitution within the same family without board modification-confirmed by Freescale's mechanical and thermal documentation for the MC68302EH25C.