NXP Semiconductors MC9S08GT8ACFDE

Overview

MC9S08GT8ACFDE from NXP (formerly Freescale) is an 8-bit HCS08 microcontroller with 8 KB flash, 512 B RAM, 40-MHz CPU, and integrated peripherals including dual SCI, SPI, I²C, 10-bit ATD, and dual TPM timer/PWM modules. It operates from 1.8–3.6 V and supports three low-power stop modes, targeting cost-sensitive industrial control and sensor interface applications.

For engineers reviewing the MC9S08GT8ACFDE datasheet, MC9S08GT8ACFDE pinout, MC9S08GT8ACFDE application, or MC9S08GT8ACFDE equivalent, key selection criteria include flash size, peripheral set (especially dual serial interfaces and 10-bit ADC), low-voltage operation down to 1.8 V, and QFN-32 package compatibility for space-constrained designs.

Technical Context

The MC9S08GT8ACFDE implements the HCS08 CPU core with HC08 instruction set extension (including BGND), supporting up to 32 interrupt/reset sources and real-time interrupt (RTI) in run/wait/stop modes. Its internal clock generator includes FLL with ±0.5% deviation across voltage and temperature, and selectable clock sources: internal trimmed RC, external crystal (32 kHz–4 MHz), or external clock.

Memory subsystem features FLASH programmable/erasable at 1.8 V, block protection, and security lock; peripherals include two independent Timer/PWM modules (TPM1: 3-channel, TPM2: 2-channel), 8-channel 10-bit ATD with software trigger, and keyboard interrupt (KBI) on Port A pins - all accessible via dedicated I/O registers with configurable pullups and slew rate control.

Key Specifications

Pinout & Package

MC9S08GT8ACFDE is housed in a 32-pin QFN (5 × 5 mm, 0.5 mm pitch) package with exposed thermal pad. Pin functions are defined per port register mapping and support multiplexed peripheral signals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with MC9S08GT16ACFDE, the MC9S08GT8ACFDE offers identical peripherals and low-power behavior but halves flash/RAM capacity - ideal for fixed-function embedded control where code size is constrained. Versus S9KEAZ128AMLH, it retains legacy toolchain compatibility and lower gate count, avoiding ARM migration complexity while meeting basic real-time I/O needs.

Availability

MC9S08GT8ACFDE is available at Aetrix Electronics and suitable for industrial sensor nodes, smart thermostat controllers, motor interface modules, and legacy protocol converters requiring stable component supply and long-term lifecycle support.

Supply support for MC9S08GT8ACFDE 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 is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT markets.

The MC9S08GT8ACFDE belongs to the HCS08 microcontroller family, designed for cost-effective, low-power embedded control in resource-constrained applications where deterministic real-time response and minimal BOM cost are critical.

FAQ

What is the maximum operating frequency of the MC9S08GT8ACFDE?

The MC9S08GT8ACFDE features a 40-MHz HCS08 CPU core with bus frequency scalable via its internal clock generator's FLL. Maximum bus frequency is 40 MHz when using external crystal or internal trimmed RC with appropriate FLL configuration. Actual achievable frequency depends on supply voltage and selected clock mode - e.g., FEI mode delivers up to 20 MHz at 1.8 V, while FEE mode reaches 40 MHz at ≥2.7 V.

Does the MC9S08GT8ACFDE support in-circuit debugging?

Yes, the MC9S08GT8ACFDE includes a single-wire background debug interface (BKGD) on PTG0, enabling full in-circuit debugging and flash programming without dedicated JTAG pins. The on-chip debug module supports breakpoint setting, real-time bus capture with 8-deep FIFO, and nine trigger modes - all accessible through standard BDM tools compatible with the HCS08 architecture.

What are the power supply requirements for the MC9S08GT8ACFDE?

The MC9S08GT8ACFDE operates from a single 1.8–3.6 V supply, with separate VDD/VSS (digital) and VDDAD/VSSAD (analog) rails. Analog supply must be clean and decoupled independently to ensure 10-bit ADC accuracy. Internal LVD circuitry monitors VDD and can generate reset or interrupt below user-configured thresholds - critical for robust operation in fluctuating power environments.

How many I/O pins does the MC9S08GT8ACFDE provide in its QFN-32 package?

In the 32-pin QFN package, the MC9S08GT8ACFDE provides up to 28 general-purpose I/O pins across Ports A–E and G, plus dedicated function pins (RESET, IRQ, BKGD, XTAL/EXTAL). Eight of these pins (PTA0–PTA7) support keyboard interrupt, and eight are rated for 20 mA sink/source - enabling direct drive of indicators or small loads without external drivers.

Is the MC9S08GT8ACFDE pin-compatible with other devices in the GT series?

Yes, the MC9S08GT8ACFDE shares identical pinout and package dimensions with the MC9S08GT16ACFDE in the 32-pin QFN variant - making them hardware-compatible replacements. Firmware and PCB layout remain unchanged when upgrading from 8 KB to 16 KB flash, provided memory map usage stays within the smaller footprint or is adapted via linker script adjustments.