NXP Semiconductors MC68302AG33C

Overview

MC68302AG33C from Freescale Semiconductor is a 32-bit integrated communications microcontroller with on-chip CPU32 core, system integration module (SIM), and queued serial module (QSM), operating at 33 MHz maximum frequency, supporting asynchronous and synchronous serial protocols including IDL, GCI, and SCP, and used in telecom line interface cards and industrial protocol gateways.

For engineers reviewing the MC68302AG33C datasheet, MC68302AG33C pinout, MC68302AG33C application, or MC68302AG33C equivalent, key selection considerations include its 33 MHz CPU32 clock timing, integrated QSM with L1CLK up to 13.3 MHz, dual-channel serial support (IDL/GCI/SCP), 16-bit external bus interface with DTACK handshake, and 144-pin PGA package with multiplexed address/data bus.

Technical Context

The MC68302AG33C implements the CPU32 32-bit instruction set architecture with 16-bit external data bus and 24-bit address bus, featuring a system integration module that manages interrupt control, timer functions, and chip select logic. Its queued serial module supports three synchronous serial protocols-IDL, GCI, and SCP-with independent clock domains and programmable frame formats.

Timing is governed by a 33 MHz input clock (EXTAL), generating internal clocks including L1CLK (≤13.3 MHz), SPCLK (4–64 clock cycles), and RCLK1/TCLK1 (up to 13.2 MHz). The device uses DTACK for asynchronous bus cycle control and supports zero- to six-wait-state memory access with AS/DS strobes and R/W control.

Key Specifications

Pinout & Package

The MC68302AG33C is housed in a 144-pin Pin Grid Array (PGA) package with 12 × 12 pin layout, requiring socketed mounting and thermal consideration for sustained 33 MHz operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68302AG33C, MC68302FC33C offers identical functionality at lower cost in benign environments, while MPC823EVRM delivers higher performance and modern peripherals at the expense of M68K firmware compatibility and increased power/complexity.

Availability

MC68302AG33C is available at Aetrix Electronics and suitable for telecom infrastructure, industrial protocol conversion, and legacy equipment modernization requiring stable component supply and long-term lifecycle support.

Supply support for MC68302AG33C 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, specializing in automotive, industrial, and networking applications.

The MC68302AG33C belongs to the Motorola/Freescale 68300 family of integrated communications microcontrollers, designed specifically for real-time protocol processing in telecom line interfaces and industrial control systems.

FAQ

What is the maximum operating frequency of the MC68302AG33C?

The MC68302AG33C operates at a maximum external clock frequency of 33 MHz applied to the EXTAL pin, enabling full-speed CPU32 core execution and timing-critical peripheral operation such as L1CLK generation up to 13.3 MHz and SPCLK output with 4–64 cycle periods. This rating is guaranteed across the industrial temperature range of −40°C to +85°C.

Does the MC68302AG33C support synchronous serial communication?

Yes, the MC68302AG33C supports synchronous serial communication through its Queued Serial Module (QSM), which implements IDL, GCI, and SCP protocols. Each protocol has dedicated clock inputs (e.g., L1CLK for IDL/GCI, SPCLK for SCP) and configurable frame formats, with timing parameters like L1CLK width low (28 ns min) and SPCLK rise/fall time (≤6 ns) specified in the datasheet.

How does the MC68302AG33C handle external memory timing?

The MC68302AG33C uses DTACK-driven asynchronous bus timing with programmable chip select (CS0–CS3) parameters. It supports zero to six wait states based on external device readiness, and timing values such as tchsl (3–15 ns), tasrv (≤7 ns), and tcldo (≤15 ns) define setup/hold/strobe relationships between clock, AS/DS, and data bus signals for reliable interfacing with SRAM, flash, or peripherals.

What package type is used for the MC68302AG33C?

The MC68302AG33C is packaged in a 144-pin Pin Grid Array (PGA) with 12 × 12 pin arrangement. This PGA variant is distinct from PLCC or QFP versions of the 68300 family and requires socketed mounting. Pin assignments for EXTAL, AS, DS, DTACK, R/W, CS outputs, and serial interface signals (L1CLK, L1SY1, SPCLK) are defined in the official Freescale MC68302 hardware manual.

Is the MC68302AG33C pin-compatible with other MC68302 variants?

The MC68302AG33C shares the same 144-pin PGA package and pinout as other AG-suffix MC68302 variants (e.g., MC68302AG25C), differing only in speed grade and temperature rating. It is not pin-compatible with FC-suffix (commercial) or LC-suffix (ceramic PGA) variants that use different packages or pin configurations, nor with later MPC8xx family members.