MC9S08QG8CFQE - 8-Bit HCS08 MCU 8KB Flash 20MHz | NXP
MPN: MC9S08QG8CFQE ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
MC9S08QG8CFQE Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, on-chip memory (Flash, RAM), peripherals (timers, ADC, communication interfaces), and I/O lines on a single semiconductor die. MCUs sit at the heart of embedded systems across consumer, industrial, and automotive products. Within the broader hierarchy, the MC9S08QG8CFQE belongs to the 8-bit microcontroller category, sits in the S08QG sub-family of the HCS08 family, and is part of NXP/Freescale's low-cost ultra-low-power MCU portfolio designed for battery-powered and space-constrained applications.
The MC9S08QG8CFQE features a 20 MHz enhanced HCS08 CPU with the HC08 instruction set plus the BGND instruction for background debugging. It provides a Background Debug System (BDCS) that supports a single breakpoint during in-circuit debugging plus two additional breakpoints in on-chip debug hardware. The integrated clock, low-power modes, and peripherals target cost-sensitive applications that still require deterministic real-time response.
The device integrates an internal clock generator, ADC, timers, and serial interfaces in a compact DFN package. Typical use cases include battery-powered sensors, remote controls, small appliances, low-end consumer electronics, and simple motor-control loops where 8-bit performance with low power consumption is more than sufficient.
This 8-pin MCU is best suited for designs where board space is highly constrained but a moderate processing capability is still needed. Engineers should pay attention to power-supply decoupling and the exposed-pad thermal/ground connection; the thermal pad must be soldered to the ground plane for both thermal dissipation and electrical reference.
This page consolidates distributor pricing, drop-in same-package alternatives, and practical design notes for the MC9S08QG8CFQE that are not available in the manufacturer datasheet alone.
Drop-in alternatives for MC9S08QG8CFQE — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MC9S08QG8CFQE (same form factor and footprint) — differing in Package, Core Processor, Instruction Set, Lifecycle Status, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08QG8CFFE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
Contact for price
View Datasheet →MC9S08QG4CFFE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.1 / Unit
View Datasheet →MC9S08QG84CFFE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.21 / Unit
View Datasheet →MC9S08QD4CSC
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
Contact for price
View Datasheet →MC908QT2ACPE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$0.75 / Unit
View Datasheet →MC9S08QG8CFQE Maximum Ratings & Electrical Characteristics
| Core | HCS08 (enhanced S08) |
| CPU Architecture | 8-bit CISC |
| Maximum CPU Frequency | 20 MHz |
| Program Memory (Flash) | 8 KB (8K x 8) |
| Supply Voltage (VDD) | 1.8 V to 3.6 V |
| I/O Pins | Up to 6 |
| Package | 8-pin DFN-EP (4x4 mm) |
| Mounting Type | Surface Mount |
| On-chip Debug | Background Debug Mode (BDCS), 1 + 2 breakpoints |
| Instruction Set | HC08 + BGND |
| ROM Type | Flash |
| RoHS Status | ROHS compliant (per datasheet) |
| Lifecycle Status | End-of-Life / Last Time Buy (per NXP product page) |
MC9S08QG8CFQE Pin Configuration
| Pin 1 | PTB5/IRQ/TCLK0/SS — General-purpose I/O / IRQ input / Timer channel / SPI SS (function-multiplexed) |
| Pin 2 | PTA2/KBI1P2/ADC0 — Port A I/O / Keyboard interrupt / ADC channel |
| Pin 3 | PTA3/KBI1P3/ADC1 — Port A I/O / Keyboard interrupt / ADC channel |
| Pin 4 | PTA4/KBI1P4/ADC2 — Port A I/O / Keyboard interrupt / ADC channel |
| Pin 5 | PTA5/KBI1P5/ADC3 — Port A I/O / Keyboard interrupt / ADC channel |
| Pin 6 | VDD — Positive supply (1.8 V to 3.6 V) |
| Pin 7 | VSS — Ground reference |
| Pin 8 | BKGD/MS — Background Debug Mode / Mode Select (used for in-circuit programming and debug) |
Typical Applications
MC9S08QG8CFQE is suitable for 6 applications: Battery-Powered Remote Control, Industrial Sensor Node, Consumer Appliance Control Panel, Wireless Sensor / IoT Edge Device, Automotive Body Electronics (Legacy), Test and Measurement Probe Module.
Battery-Powered Remote Control
The MC9S08QG8CFQE fits battery-powered remote-control designs because it operates from a 1.8 V to 3.6 V supply, supports the HCS08 low-power stop and wait modes, and integrates all required peripherals on-die to keep BOM small in a 4x4 mm DFN-EP footprint. Its 20 MHz HCS08 core handles IR/button scanning and short-range RF protocol encoding without external logic. The 8 KB Flash is enough for key-decoding tables, protocol state machines, and a small bootloader. Versus discrete designs, the part reduces quiescent current dramatically and extends CR2032 battery life.
Recommended
Industrial Sensor Node
For low-cost industrial 4-20 mA loop-powered or two-cell battery sensor nodes, the MC9S08QG8CFQE provides a deterministic 8-bit HCS08 core at 20 MHz, on-chip ADC, and timers needed to sample analog signals and drive a digital output. The 1.8 V to 3.6 V supply lets the node run directly from a step-up converter output or a two-cell alkaline battery. Its small DFN-EP 8-pin package allows the entire node - MCU + sensor + isolation - to fit inside a sensor housing with minimal PCB area, which is critical for industrial field-mounted devices.
Recommended
Consumer Appliance Control Panel
The MC9S08QG8CFQE suits small white-goods control-panel applications such as coffee machines, small kitchen appliances, and personal-care devices. It supports capacitive/segmented-display button interfaces, simple LED driving, and a serial interface to a main appliance controller. The 6 GPIO pins map cleanly onto a 4-6 button plus LED matrix. Its low-voltage supply range lets it run directly from rectified mains via a small capacitive dropper, while the Flash-based program memory allows last-minute firmware tuning in production.
Recommended
Wireless Sensor / IoT Edge Device
The MC9S08QG8CFQE is a strong fit for the edge side of wireless sensor and IoT endpoints where a small MCU must wake briefly to gather sensor data, transmit via an attached radio module, and return to sleep. The HCS08 core handles simple sensor fusion and protocol framing in firmware, and the BGND-based debug interface allows firmware updates in factory test fixtures. Combined with a sub-GHz or BLE radio on a small SPI/UART peripheral, the part helps a coin-cell sensor node achieve multi-year battery life in IoT deployments.
Recommended
Automotive Body Electronics (Legacy)
Though S08QG-family parts are not AEC-Q100 qualified, the MC9S08QG8CFQE has historically been used in non-safety automotive body electronics such as interior LED modules, simple switch panels, and HVAC accessories. Its small DFN-EP footprint, 1.8 V to 3.6 V supply tolerance, and Flash-based memory allow it to fit space-tight body modules that connect to a CAN/LIN backbone via an external transceiver. Modern designs should consider the Q-series AEC-Q100 parts in the same family or higher up the S12 portfolio.
Recommended
Test and Measurement Probe Module
The MC9S08QG8CFQE can serve as the local controller inside compact test-and-measurement probes and breakout boards where space is at a premium. Its on-chip ADC and timers, combined with deterministic 8-bit performance at 20 MHz, let it capture analog waveforms or count pulses and stream the data via a serial interface to a host. The exposed-pad DFN package dissipates heat well enough for continuous sampling at moderate duty cycles. The 8 KB Flash holds calibration data and a small protocol stack, while the BGND pin simplifies field firmware updates.
Recommended
Recommended Products Summary
Engineering reference data for MC9S08QG8CFQE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08QG8CFFE | MC9S08QG4CFFE | MC9S08QG84CFFE | MC9S08QD4CSC | MC908QT2ACPE |
|---|---|---|---|---|---|---|
| Package | DFN-EP 8-pin (4x4 mm) | DFN-EP 8-pin (4x4 mm) - same | DFN-EP 8-pin (4x4 mm) - same | DFN-EP 8-pin (4x4 mm) - same | DFN 8-pin family footprint | DIP-8 / S08 small-package family |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core | HCS08 8-bit | HCS08 8-bit | HCS08 8-bit | HCS08 8-bit | HCS08 8-bit | HC08 8-bit |
| Maximum CPU Clock | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 10 MHz | 8 MHz |
| Program Memory (Flash) | 8 KB | 8 KB | 4 KB | 8 KB | 4 KB | 1.5 KB |
| Supply Voltage | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 3.0 V to 5.5 V |
| GPIO Pins | Up to 6 | Up to 6 | Up to 6 | Up to 6 | Up to 4 | Up to 5 |
| On-chip Debug | BDCS (1+2 breakpoints) | BDCS (1+2 breakpoints) | BDCS (1+2 breakpoints) | BDCS (1+2 breakpoints) | BDCS | MON08 (legacy HC08 debug) |
| Automotive Grade (AEC-Q100) | Not qualified | Not qualified | Not qualified | Not qualified | Not qualified | Not qualified |
Key Differentiators
- Smallest 8 KB Flash S08 part available in DFN-EP 8 (vs MC9S08QG4CFFE)
- 20 MHz HCS08 core (vs 8 MHz on legacy MC908) (vs MC908QT2ACPE)
- Background Debug Mode support (vs MC908QT2ACPE)
Design Notes
The MC9S08QG8CFQE uses an 8-pin DFN-EP package whose exposed thermal pad is electrically the ground reference. The pad MUST be soldered to a continuous PCB ground copper pour with at least two thermal vias tied to the opposite-side ground plane. Skipping the exposed-pad connection causes both thermal dissipation and electrical-ground instability, resulting in intermittent resets or analog-channel errors. Estimated: 4 thermal vias of 0.3 mm drill are sufficient for typical 100 mA average loads.
Place a 100 nF ceramic decoupling capacitor within 3 mm of the VDD pin and an additional 10 uF bulk capacitor on the same rail to handle HC08/HCS08 in-rush currents during Flash programming and clock transitions. The part operates down to 1.8 V; below that, Flash programming may fail. Keep the supply rail well below 3.6 V to avoid latch-up. Estimated: an additional 4.7 uF on the programming-tool VDD line typically eliminates programming failures during production.
Do NOT confuse the BGGD/MS pin (background debug / mode select) with a general-purpose GPIO. It is used for in-circuit programming by CodeWarrior / P&E tools and must be accessible on the PCB. Driving the BKGD pin to a logic-low at reset enters MCU active-background mode; a 10 k pull-up to VDD is recommended when not actively debugged. Sharing this pin with a strong external driver can prevent the debugger from taking control.
Although 8-bit MCUs running at 20 MHz tolerate simple board layouts, keep the BKGD trace away from switching power and high-current LED traces by at least 3 mm. Place a series 4.7 k resistor near the BKGD pin if you expect long debug-cable runs, which prevents ringing during programming. Estimated: for cable lengths above 30 cm, the resistor is required; below 10 cm, the resistor can be omitted on compact boards.
Compliance Information
RoHS compliance per NXP/Freescale datasheet and DigiKey listing. AEC-Q100: not qualified - do not use in safety-critical automotive applications. REACH, halogen-free, and conflict-minerals status not explicitly listed in the verified data - flagged as unknown.
