NXP Semiconductors MC68LC302AF16VCT

Overview

MC68LC302AF16VCT from Freescale is a low-power, static-core integrated multiprotocol processor based on the M68000 architecture, featuring a 16.67 MHz CPU clock, dual SCCs, 1152-byte on-chip dual-port RAM, and support for 32 kHz or 4 MHz crystal input via on-chip PLL. It serves as a space- and power-optimized alternative to the MC68302 in embedded communications and portable control systems.

For engineers reviewing the MC68LC302AF16VCT datasheet, MC68LC302AF16VCT pinout, MC68LC302AF16VCT application, or MC68LC302AF16VCT equivalent, key selection considerations include its 100-pin TQFP package, absence of SCC3, glueless memory interface (WEH/WEL/OE), low-power wake-up capability via PIT or two dedicated pins, and static core enabling full stop-mode operation.

Technical Context

The MC68LC302AF16VCT integrates a static 68000 core with dual full-duplex serial communication controllers (SCC1/SCC2) supporting HDLC/SDLC, UART, and BISYNC protocols. Its system integration block (SIB) includes three timers (one watchdog, one periodic interrupt timer), four chip-select lines with wait-state logic, and programmable address mapping for dual-port RAM and IMP registers.

It implements a dedicated on-chip PLL supporting 32 kHz or 4 MHz crystal inputs, generating internal clocks without external frequency multipliers. The device retains CPU disable (slave) mode for intelligent peripheral operation but removes external bus arbitration signals (BG/BGACK/BR) and SCC3, reducing pin count from 132 to 100 while maintaining core IMP functionality.

Key Specifications

Pinout & Package

MC68LC302AF16VCT is housed in a 100-pin Thin Quad Flat Pack (TQFP) with 0.5 mm pitch, lead-free and RoHS-compliant. Package dimensions are 14 mm × 14 mm × 1.4 mm max height, suitable for space- and height-constrained applications including PCMCIA cards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar integrated multiprotocol processor applications.

Compared with MC68302RC20 and MC68332ACPV16, the MC68LC302AF16VCT trades SCC3 and bus arbitration for lower power, smaller footprint, and simpler memory interfacing - making it optimal for cost- and size-sensitive portable or embedded communications nodes where two serial channels suffice.

Availability

MC68LC302AF16VCT is available at Aetrix Electronics and suitable for industrial RTUs, PCMCIA communications cards, and low-power handheld terminals requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MC68LC302AF16VCT 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) was a leading designer of embedded processors, microcontrollers, and analog chips for automotive, industrial, and networking markets.

The MC68LC302 product line delivers cost-optimized, low-power variants of the MC68302 IMP family - targeting portable, space-constrained, and battery-operated communications equipment where full bus arbitration and triple serial channels are unnecessary.

FAQ

What is the operating voltage range for the MC68LC302AF16VCT?

The MC68LC302AF16VCT operates at 3.3 V ± 0.3 V, as indicated by the "V" suffix in the order number. This single-supply configuration eliminates the need for separate I/O and core voltage rails, simplifying power design compared to 5 V variants like MC68LC302PU16. All I/O pins are 3.3 V tolerant, and the internal PLL and static core are optimized for this voltage level. The MC68LC302AF16VCT does not support 5 V operation.

Does the MC68LC302AF16VCT support external bus mastering?

No, the MC68LC302AF16VCT does not support external bus mastering. Bus arbitration pins (BG, BR, BGACK) were removed to achieve the 100-pin TQFP package. While an external master can assert HALT to pause the CPU, true bus ownership transfer is unsupported. In contrast, the MC68302 retains full bus arbitration. The MC68LC302AF16VCT is intended for standalone or slave-mode use - not multi-master bus systems.

How many serial communication controllers does the MC68LC302AF16VCT include?

The MC68LC302AF16VCT includes two independent full-duplex serial communication controllers (SCC1 and SCC2), each supporting HDLC/SDLC, UART, BISYNC, and transparent modes. SCC3 - present in the MC68302 - is omitted entirely. This reduction aligns with the device's focus on cost and power optimization for applications needing only two protocol-capable serial interfaces, such as dual-fieldbus nodes or modem + debug port configurations.

What clock sources does the MC68LC302AF16VCT support?

The MC68LC302AF16VCT supports two crystal-based clock inputs: 32 kHz for ultra-low-power RTC-like operation or 4 MHz for general-purpose timing. The MODCLK pin is sampled at reset to select the source, after which it becomes general-purpose I/O (PA12). The on-chip PLL generates the internal CPU and peripheral clocks - eliminating external clock generators. This dual-option design makes the MC68LC302AF16VCT adaptable to both battery-backed and mains-powered systems.

Is the MC68LC302AF16VCT pin-compatible with other MC68LC302 variants?

Yes, the MC68LC302AF16VCT shares identical pinout and electrical characteristics with all other 100-pin TQFP variants (e.g., MC68LC302PU16V, MC68LC302CPU16V), differing only in temperature grade (0°C to 70°C for "A", –40°C to +85°C for "C") and marking. The "F" in MC68LC302AF16VCT denotes Freescale's standard industrial-grade marking, and "CT" confirms the TQFP package. No PCB redesign is needed when migrating between these speed/temperature/package-matched variants.