NXP Semiconductors MC9S08QG4CFKE

Overview

MC9S08QG4CFKE from NXP (formerly Freescale) is an 8-bit HCS08 microcontroller with 4 KB flash, 256 bytes RAM, 20-MHz CPU, and integrated peripherals including 10-bit ADC, SCI, SPI, I²C, TPM, ACMP, and MTIM. It operates in industrial temperature range and targets low-cost embedded control in space-constrained applications such as appliance sub-systems and sensor nodes.

For engineers reviewing the MC9S08QG4CFKE datasheet, MC9S08QG4CFKE pinout, MC9S08QG4CFKE application, or MC9S08QG4CFKE equivalent, key selection criteria include its 8-pin SOIC package, single-wire background debug interface, internal clock source with FLL, COP watchdog, and low-voltage detection - all critical for cost-sensitive, battery-aware MCU designs requiring minimal external components.

Technical Context

The MC9S08QG4CFKE implements the HCS08 CPU core with HC08 instruction set plus BGND, supporting in-circuit debugging via a single-wire BDM interface and up to three breakpoints. Its debug module includes two comparators, nine trigger modes, and an eight-deep FIFO for flow-event capture.

It integrates dual clock sources: ICS with frequency-locked loop (FLL) enabling bus frequencies from 1–10 MHz using trimmed internal reference (±2% over voltage/temperature), and XOSC supporting crystal/resonator inputs from 31.25 kHz to 16 MHz or external clock up to 20 MHz.

Key Specifications

Pinout & Package

MC9S08QG4CFKE is housed in an 8-pin narrow-body SOIC package (body width 3.9 mm), optimized for PCB area efficiency and manual assembly. Pin functions are validated per Freescale DS rev. 5 (2009), with dedicated RESET, BKGD/MS, VDD/VSS, and six general-purpose I/O pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC9S08QG4CFKE, MC9S08QG4CDTE offers higher I/O density in larger package, while MC9RS08KA2CSC trades peripheral richness for deeper sleep and smaller memory - making MC9S08QG4CFKE optimal for compact, feature-balanced control tasks requiring debug access and mixed-signal integration.

Availability

MC9S08QG4CFKE is available at Aetrix Electronics and suitable for home appliance control, industrial sensor nodes, smart lighting dimmers, and POS peripheral controllers requiring stable component supply and long-term industrial availability.

Supply support for MC9S08QG4CFKE 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 company formed from the spin-off of Freescale Semiconductor and Philips' semiconductor division, specializing in secure connectivity solutions for automotive, industrial, and IoT markets.

The MC9S08QG4CFKE belongs to the legacy HCS08 microcontroller family designed for cost-sensitive, low-pin-count embedded control applications demanding high reliability, integrated analog peripherals, and streamlined debug capability.

FAQ

What is the maximum operating frequency of the MC9S08QG4CFKE CPU core?

The MC9S08QG4CFKE features an HCS08 CPU core rated for up to 20 MHz operation. Bus frequency is derived from the internal clock source (ICS) or external oscillator (XOSC), with ICS supporting 1–10 MHz bus speeds via its FLL. The 20-MHz rating reflects core timing margin under specified VDD (2.7–3.6 V) and temperature (–40°C to +85°C) conditions per Freescale DS rev. 5.

Does the MC9S08QG4CFKE support in-circuit debugging, and what interface is used?

Yes, the MC9S08QG4CFKE supports in-circuit debugging via a single-wire background debug mode (BDM) interface using the BKGD/MS pin. This interface enables real-time bus capture, breakpoint setting (one active + two in debug module), and memory/register access without halting full system operation - essential for rapid firmware validation on the MC9S08QG4CFKE.

What are the supported power-saving modes on the MC9S08QG4CFKE, and how do they differ?

The MC9S08QG4CFKE supports Wait mode and three Stop modes (Stop1, Stop2, Stop3). Stop3 disables all clocks except RTC and offers lowest current (<1 µA); Stop2 retains TPM and ADC clocks; Stop1 keeps ICS running for fast wake-up. All modes retain RAM content and support wake-up via IRQ, RTI, or ACMP - critical for deterministic low-power behavior in the MC9S08QG4CFKE.

Can the MC9S08QG4CFKE's ADC operate without an external voltage reference?

Yes, the MC9S08QG4CFKE's 10-bit ADC includes an internal bandgap reference channel and temperature sensor, allowing fully self-contained analog measurements without external VREFH/VREFL. It supports asynchronous clocking and hardware triggering via RTI - enabling precise, low-overhead sampling in resource-constrained applications using the MC9S08QG4CFKE.

Is the MC9S08QG4CFKE pin-compatible with other members of the QG4 family, such as the MC9S08QG4CDTE?

No, the MC9S08QG4CFKE (8-pin SOIC) is not pin-compatible with the MC9S08QG4CDTE (16-pin TSSOP). They share identical core architecture and register mapping but differ in package, pin count, and I/O allocation. The MC9S08QG4CFKE provides six GPIO pins plus RESET, BKGD/MS, IRQ, VDD, and VSS; the CDTE variant offers twelve GPIO and different peripheral pinouts - requiring PCB redesign for substitution.