NXP Semiconductors MC68302AG16C

Overview

MC68302AG16C from Freescale Semiconductor is a single-chip integrated multi-protocol processor featuring an MC68000/MC68008 microprocessor core, a dedicated RISC-based communications processor (CP), and a system integration block (SIB). It operates at 16 MHz, integrates 1152 bytes of on-chip dual-port RAM, supports HDLC/SDLC/UART/DDCMP/Totally Transparent protocols via three SCCs, and targets ISDN terminal adapters and data concentrators.

For engineers reviewing the MC68302AG16C datasheet, MC68302AG16C pinout, MC68302AG16C application, or MC68302AG16C equivalent, key selection considerations include its 16 MHz clock rating, triple SCC with protocol flexibility, dual-port RAM size, TQFP-132 package footprint, and support for concurrent multi-protocol operation without CPU intervention.

Technical Context

The MC68302AG16C implements a tightly coupled architecture where the MC68000 core handles general-purpose processing while the independent RISC-based communications processor manages serial protocol stacks. Its three full-duplex Serial Communication Controllers (SCCs) each support HDLC/SDLC, UART, DDCMP, Bisync, and Totally Transparent modes, with six dedicated serial DMA channels enabling frame buffering without CPU involvement.

System-level features include an IDMA controller, interrupt controller with two operating modes, four programmable chip-select lines with wait-state logic, three timers (including software watchdog), DRAM refresh controller, and on-chip clock generator. The SIB provides bus arbitration, low-latency interrupt handling, freeze control for debugging, and standby power management.

Key Specifications

Pinout & Package

MC68302AG16C is housed in a 132-pin Thin Quad Flat Pack (TQFP) package with 0.4 mm lead pitch and 20.0 × 20.0 mm body size. Pin assignments follow Motorola/Freescale standard MC68302 pinout layout, supporting multiplexed address/data bus, peripheral control signals, and dedicated serial interface pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-protocol communications processor applications.

Compared with MC68EN302 and MC68LC302, the MC68302AG16C delivers optimal balance of protocol breadth, deterministic serial throughput, and mature toolchain support for fixed-line ISDN and legacy telecom equipment-without over-provisioning Ethernet or ultra-low-power features.

Availability

MC68302AG16C is available at Aetrix Electronics and suitable for ISDN terminal adapters, data concentrators, and modem controller designs requiring stable component supply across long-lifecycle industrial deployments.

Supply support for MC68302AG16C 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's semiconductor division.

The MC68302AG16C belongs to Freescale's legacy Communications Processor family, engineered specifically for cost-sensitive, real-time telecom infrastructure requiring integrated protocol acceleration and minimal external components.

FAQ

What is the maximum operating frequency of the MC68302AG16C?

The MC68302AG16C is rated for a maximum clock frequency of 16 MHz, as indicated by the "G16" suffix in its part number. This speed is guaranteed across commercial temperature range (0°C to +70°C) and defines the upper limit for instruction execution rate, serial bit timing accuracy, and real-time interrupt response. The device requires a stable 16 MHz input clock on the CLKIN pin to achieve full specification compliance.

Does the MC68302AG16C support V.110 protocol, and how is it implemented?

Yes, the MC68302AG16C supports V.110 protocol through its three Serial Communication Controllers (SCCs), as confirmed in Freescale's official MC68302 technical documentation. V.110 is implemented in hardware within the SCCs' protocol engine, enabling asynchronous-to-synchronous conversion and rate adaptation for ISDN data services without CPU overhead. This capability is active in both SCC1 and SCC2 when configured in V.110 mode.

How much on-chip memory does the MC68302AG16C integrate, and what is its architecture?

The MC68302AG16C integrates 1152 bytes of on-chip dual-port static RAM. This memory is architecturally shared between the MC68000 core and the RISC-based communications processor, allowing concurrent read/write access from both domains without arbitration delay. It is mapped into the processor's address space and supports programmable address alignment for flexible peripheral register allocation.

Is the MC68302AG16C pin-compatible with other MC68302 derivatives like the MC68QH302?

No, the MC68302AG16C is not pin-compatible with the MC68QH302. While both belong to the MC68302 family, the MC68QH302 uses a 144-pin TQFP package and adds a dual-channel SCC, whereas the MC68302AG16C uses a 132-pin TQFP package with three standard SCCs. Physical pin count, spacing, and signal assignment differ significantly-requiring PCB redesign for substitution.

What debug features does the MC68302AG16C provide for embedded firmware development?

The MC68302AG16C includes freeze control logic that halts selected on-chip peripherals-including SCCs, timers, and IDMA-while allowing the CPU to remain operational for register inspection and breakpoint insertion. It also supports hardware watchdog reset and low-latency interrupt handling for real-time tracing. These features are accessible via JTAG-compatible boundary-scan test access port defined in the MC68302AG16C pinout specification.