NXP Semiconductors MC908GR32ACFJE

Overview

MC908GR32ACFJE from Freescale Semiconductor is an 8-bit HCS08-core microcontroller with 32 KB on-chip Flash memory, 1 KB RAM, and integrated peripherals including ADC (8-channel, 10-bit), ESCI (LIN-capable UART), SPI, two TIM modules, and a PLL-based clock generator. It operates at up to 8 MHz bus frequency and supports 5.0 V operation in industrial temperature range (–40°C to +85°C), targeting embedded control in automotive body electronics and industrial sensors.

For engineers reviewing the MC908GR32ACFJE datasheet, MC908GR32ACFJE pinout, MC908GR32ACFJE application, or MC908GR32ACFJE equivalent, key selection criteria include its LIN-compliant ESCI interface, 32 KB Flash with block protection, 10-bit ADC with internal reference, low-power stop/wait modes, and compatibility with HC08 development tools and legacy M68HC08 firmware.

Technical Context

The MC908GR32ACFJE implements the HCS08 CPU core with enhanced addressing modes and a 16-bit index register, executing instructions at up to 8 MHz bus speed derived from a PLL-locked crystal oscillator (1–8 MHz input). Its CGM supports automatic PLL acquisition and manual bandwidth control for jitter-sensitive timing.

It integrates dual timer modules (TIM1/TIM2) with input capture, output compare, and PWM generation; an ESCI module supporting LIN 1.3/2.0 master/slave operation via break detection and sync field handling; and a 10-bit ADC with programmable sample time, left/right justification, and 8-channel multiplexing across Port A and Port B pins.

Key Specifications

Pinout & Package

MC908GR32ACFJE is housed in a 52-pin QFP (Quad Flat Package) with 0.65 mm pitch, JEDEC MS-026 compliant, suitable for automated SMT assembly and thermal management in dense PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908GR32ACFJE, MC908GR32MFJE offers lower unit cost at scale but sacrifices field update capability, while MC9S08GR32CPJ delivers superior Flash reliability and debugging without layout changes - making it the recommended migration path for long-lifecycle products.

Availability

MC908GR32ACFJE is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor nodes, appliance motor controllers, and building automation panels requiring stable component supply and long-term obsolescence management.

Supply support for MC908GR32ACFJE 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) pioneered 8-bit MCU architectures for automotive and industrial markets, emphasizing robustness, toolchain maturity, and qualification to AEC-Q100 standards.

The MC908GR32ACFJE belongs to the HCS08 GR-series, designed specifically for cost-sensitive, functionally integrated control applications where LIN connectivity, analog sensing, and low-power operation are essential - especially in body electronics and distributed sensor systems.

FAQ

What is the maximum bus frequency supported by the MC908GR32ACFJE?

The MC908GR32ACFJE supports a maximum bus frequency of 8 MHz, achieved via its integrated PLL-based Clock Generator Module (CGM) locking to an external crystal (1–8 MHz). This frequency is used for CPU execution, peripheral timing, and instruction cycle synchronization - enabling real-time response in motor control and LIN communication tasks within the MC908GR32ACFJE's operational envelope.

Does the MC908GR32ACFJE include hardware support for LIN communication?

Yes, the MC908GR32ACFJE includes an Enhanced Serial Communications Interface (ESCI) module explicitly designed for LIN 1.3 and LIN 2.0 compliance. It provides hardware break detection, sync field generation, and slave response timing control - all critical for deterministic LIN frame handling without CPU-intensive bit-banging, confirming full LIN functionality within the MC908GR32ACFJE's peripheral set.

What are the ADC capabilities of the MC908GR32ACFJE?

The MC908GR32ACFJE features a 10-bit successive approximation ADC with 8 input channels multiplexed across Port A and Port B pins (AD0–AD15). It supports programmable sample time, left/right result justification, and ±1 LSB integral nonlinearity - enabling accurate analog sensor interfacing. The ADC operates from the same 5 V supply as the core, with dedicated VDDAD/VSSAD pins for noise isolation, as specified in the MC908GR32ACFJE datasheet.

Is the MC908GR32ACFJE pin-compatible with other devices in the GR-series?

Yes, the MC908GR32ACFJE shares the same 52-pin QFP package and pin assignment with MC68HC908GR48A and MC68HC908GR60A, differing only in Flash size (32 KB vs. 48 KB vs. 60 KB) and RAM allocation. This allows hardware reuse across product variants - for example, a single PCB can support all three GR-series parts by populating the appropriate Flash density, preserving layout integrity and test fixtures for the MC908GR32ACFJE and its siblings.

What debug and programming interfaces does the MC908GR32ACFJE support?

The MC908GR32ACFJE supports Background Debug Mode (BDM) via a single-wire interface using the BKGD pin, enabling in-circuit debugging, flash programming, and real-time register inspection without halting system operation. This BDM interface is fully supported by Freescale's CodeWarrior IDE and third-party emulators - providing standardized development access across the entire HCS08 family, including the MC908GR32ACFJE.