NXP Semiconductors MC68336GCAB20

Overview

MC68336GCAB20 from NXP (formerly Motorola) is a 16-bit CISC microcontroller with integrated Time Processing Unit (TPU), 20.97 MHz CPU clock, 512 KB on-chip ROM, and 160-pin QFP package. It serves as a real-time control engine in industrial motion systems, supporting deterministic I/O timing via TPU channels and external bus interfacing for memory expansion.

For engineers reviewing the MC68336GCAB20 datasheet, MC68336GCAB20 pinout, MC68336GCAB20 application, or MC68336GCAB20 equivalent, key selection criteria include TPU channel count (16), external bus width (16-bit data/24-bit address), analog input capability (60-channel ADC with 10-bit resolution), and industrial temperature range (–40 to +105 °C).

Technical Context

The MC68336GCAB20 implements a full Harvard architecture with separate instruction and data buses, enabling concurrent fetch and execute operations. Its TPU operates independently of the CPU core, executing preloaded microcode sequences to manage up to 16 time-critical I/O functions including PWM generation, quadrature decoding, and pulse-width measurement.

CPU execution uses a 16-bit data path with 24-bit addressing, supporting external memory mapping across 11 chip-select regions. The device integrates dual 10-bit ADCs (AN0–AN59), programmable interrupt controller (IRQ0–IRQ7), and synchronous serial interface (SPI-compatible PQS module) for sensor and actuator communication.

Key Specifications

Pinout & Package

MC68336GCAB20 is housed in a 160-pin plastic QFP (Case 864A-03), measuring 28.0 mm × 28.0 mm × 3.5 mm with 0.65 mm lead pitch. Pin 1 and Pin 160 are NC (no connect) for revision D and later, ensuring pin compatibility with MC68376.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller-based real-time control applications.

Compared with MC68336GCAB20, MC68376BGCFT20 adds CAN but reduces ROM size and removes mask-programming option, while MC9328MX1CZK trades deterministic timing for processing throughput and OS readiness - making MC68336GCAB20 optimal for hard real-time embedded control where microsecond-level I/O predictability is non-negotiable.

Availability

MC68336GCAB20 is available at Aetrix Electronics and suitable for industrial motion control, programmable logic controller (PLC), and automated test equipment (ATE) requiring stable component supply and long-term obsolescence management.

Supply support for MC68336GCAB20 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

NXP Semiconductors (originally Motorola Semiconductor) designs high-reliability microcontrollers for industrial, automotive, and aerospace applications, with deep heritage in 68K architecture and real-time embedded systems.

The MC68336GCAB20 belongs to the M68300 family of integrated microcontrollers engineered specifically for deterministic real-time control - emphasizing hardware-accelerated I/O timing, robust analog integration, and industrial environmental resilience.

FAQ

What is the maximum operating frequency of the MC68336GCAB20?

The MC68336GCAB20 operates at a maximum CPU clock frequency of 20.97 MHz, derived from an external crystal (XTAL/EXTAL) through an on-chip PLL. This frequency is fixed for the GCAB20 variant and validated across the full –40 °C to +105 °C temperature range with 4.5–5.5 V supply.

Does the MC68336GCAB20 include on-chip RAM?

No, the MC68336GCAB20 contains 512 KB of mask-programmed ROM but no on-chip RAM. System RAM must be provided externally via the 16-bit data bus and 24-bit address bus, with dedicated control signals (AS, DS, R/W, SIZ0/SIZ1) for timing-critical access.

How many analog input channels does the MC68336GCAB20 support?

The MC68336GCAB20 supports 60 analog input channels (AN0 through AN59), routed to two independent 10-bit successive-approximation ADCs. Each ADC has its own sample-and-hold and conversion trigger sources, including TPU events and software commands.

Is the MC68336GCAB20 pin-compatible with the MC68376?

Yes - MC68336GCAB20 revision D and later (including GCAB20) designate Pins 1 and 160 as NC to ensure mechanical and pinout compatibility with the MC68376. Signal assignments for all other 158 pins match identically between the two devices in 160-pin QFP packages.

What is the role of the TPU in the MC68336GCAB20?

The Time Processing Unit (TPU) in the MC68336GCAB20 is a dedicated 16-channel coprocessor that executes microcode-driven timing functions - including PWM generation, quadrature decoding, input capture, and output compare - without CPU involvement, guaranteeing sub-microsecond response determinism for critical I/O tasks.