MC9S08QG8CFFE - 8-bit S08 MCU, 8KB Flash, 20MHz | NXP
MPN: MC9S08QG8CFFE ✗ End of Life| 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 |
MC9S08QG8CFFE Overview
An 8-bit microcontroller (MCU) integrates a processor core, program memory, data memory, and peripherals onto a single chip. Within the power-management and embedded-control hierarchy, the HCS08 family sits in the cost-sensitive general-purpose MCU segment, where low pin count, small package, and low power consumption matter more than raw processing throughput. The S08QG family brings serial interfaces and peripherals normally found in higher-end devices into a very small footprint.
Key features include the 20 MHz HCS08 central processor unit using the HC08 instruction set with the added BGND instruction, 8KB of on-chip Flash program memory, an on-chip background debugging system with breakpoint capability for in-circuit debugging, and the low-power S08 architecture suited to battery-powered products. The exposed-pad QFN package improves thermal performance and provides a compact 5x5 mm land pattern.
Technically, the device uses the enhanced HCS08 core, which maintains HC08 object-code compatibility while adding background debug mode (BDM) access, and the family data sheet spans 352 pages covering all module variants, including an addendum for the QFN package migration from the original SOIC/DFN offerings. Typical applications include small home appliances, battery-powered handheld instruments, low-cost sensor nodes, and simple industrial control tasks where 8KB of code space and a 20 MHz bus are sufficient.
A key design consideration: because this part is End-of-Life per NXP, new designs should plan for last-time-buy stock or qualifying the same-family pin-compatible variants listed on this page before committing the PCB footprint.
This page synthesizes distributor availability, drop-in alternatives, cross-reference findings, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for MC9S08QG8CFFE — 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 MC9S08QG8CFFE (same form factor and footprint) — differing in Package, ADC, Instruction Set, RoHS Status, Lifecycle Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08QG8CFFER
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S08QG8CDTE
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →MC9S08QG8CDNE
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC9S08QG8CFQE
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC9S08QG4CFFE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.1 / Unit
View Datasheet →MC9S08QG4CDNE
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
Contact for price
View Datasheet →MC9S08QG8CFFE Maximum Ratings & Electrical Characteristics
| Core Processor | S08 |
| Core Size | 8-Bit |
| Bus Speed | 20 MHz |
| Flash Memory | 8KB (8K x 8) |
| Instruction Set | HC08 with added BGND instruction |
| Package | 16-QFN-EP (5x5 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Supplier Device Package | QFN-16 |
| Program Memory Type | FLASH |
| On-Chip Debug | Background debugging system with breakpoint capability |
| Family | HCS08 / S08QG |
| Peripherals | Serial interfaces and peripherals typical of S08QG family |
| Lifecycle Status | End of Life (per NXP product page) |
MC9S08QG8CFFE Pin Configuration
| Pin 1 | PTA0/KBIP0 — General-purpose I/O port A, bit 0 / keyboard interrupt |
| Pin 2 | PTA1/KBIP1 — General-purpose I/O port A, bit 1 / keyboard interrupt |
| Pin 3 | PTA2/BKGD/MS — Port A bit 2 / background debug / mode select |
| Pin 4 | VDD — Power supply |
| Pin 5 | VSS — Ground |
| Pin 6 | PTA3 — General-purpose I/O port A, bit 3 |
| Pin 7 | PTB0 — General-purpose I/O port B, bit 0 |
| Pin 8 | PTB1 — General-purpose I/O port B, bit 1 |
| Pin 9 | PTB2 — General-purpose I/O port B, bit 2 |
| Pin 10 | PTB3 — General-purpose I/O port B, bit 3 |
| Pin 11 | PTB4 — General-purpose I/O port B, bit 4 |
| Pin 12 | PTB5 — General-purpose I/O port B, bit 5 |
| Pin 13 | PTB6 — General-purpose I/O port B, bit 6 |
| Pin 14 | PTB7 — General-purpose I/O port B, bit 7 |
| Pin 15 | VDDAD/VREFH — Analog supply / ADC high reference |
| Pin 16 | VSSAD/VREFL — Analog ground / ADC low reference |
Typical Applications
MC9S08QG8CFFE is suitable for 6 applications: Battery-Powered Handheld Devices, Small Home Appliances, Low-Cost Sensor Nodes, Simple Industrial Control, Consumer Electronics Subsystems, Legacy Design Maintenance.
Battery-Powered Handheld Devices
The low-power S08 architecture of the MC9S08QG8CFFE is specifically called out by NXP as a fit for battery-powered devices. In a handheld instrument, the MCU sleeps between button presses and periodically polls a sensor over I2C or SPI, waking on keyboard interrupt or a low-power timer. The 20 MHz core handles menu logic and display updates fast enough that users perceive no lag, while the 8KB Flash stores application code and calibration constants without external memory. The 5x5 mm QFN package keeps the PCB small enough for compact enclosures. Designs should exploit the S08 low-power wait/stop modes and the on-chip debug interface for field firmware updates during development.
Recommended
Small Home Appliances
Small appliances such as coffee makers, fans, and personal-care devices need simple state-machine control, a few button inputs, and LED or segment-display outputs - exactly the I/O and code-size envelope of the MC9S08QG8CFFE. The 20 MHz S08 core executes control loops deterministically without an RTOS, and the 8KB Flash accommodates the application plus safety interlock code. The exposed-pad QFN-16 offers good thermal and mechanical robustness on low-layer-count consumer PCBs. Because the appliance market is price-sensitive and this part is End-of-Life, new appliance designs should evaluate the same-footprint S08QG variants to preserve the certified layout while securing supply.
Recommended
Low-Cost Sensor Nodes
The S08QG family provides serial interfaces normally found in higher-end devices, making the MC9S08QG8CFFE well suited to sensor nodes that read an ADC or digital sensor and forward data over a serial link. A typical node samples a temperature or humidity sensor every few seconds, applies offset/gain correction stored in Flash, and streams readings through the on-chip serial peripheral. The MCU spends most of its life in stop mode, so average current stays in the microamp range - a decisive advantage for coin-cell or energy-harvesting nodes. The 16-pin QFN keeps the node PCB under 1 square centimeter. End-of-life status makes the pin-compatible family variants important for long-lived deployments.
Recommended
Simple Industrial Control
In industrial sub-systems - small motor start/stop logic, limit-switch monitoring, and status signaling - the MC9S08QG8CFFE supplies deterministic 8-bit control with the ruggedness of on-chip debug for commissioning. The background debugging system with breakpoint capability lets field engineers inspect registers through the single-wire BDM interface without disturbing the control loop, which shortens on-site bring-up. The 8KB Flash holds ladder-like control logic plus a simple Modus/serial polling routine. The QFN-16 package survives the vibration typical of control cabinets when properly soldered with the exposed pad anchored. Industrial buyers should note the EOL status and qualify MC9S08QG8CDTE or MC9S08QG8CDNE as validated alternates on the same footprint.
Recommended
Consumer Electronics Subsystems
Within larger consumer products - chargers, toys, remote controls, small displays - the MC9S08QG8CFFE acts as the low-cost supervisor MCU handling key scanning, LED indication, and simple protocol communication. The HC08 instruction set with the added BGND instruction keeps firmware development toolchain-friendly, while 8KB Flash is ample for these compact applications. The 5x5 mm QFN-EP footprint fits dense multi-board consumer assemblies and its exposed pad simplifies reflow soldering on high-volume SMT lines. Since consumer programs run years, design teams should dual-source the footprint with MC9S08QG8CFFER and MC9S08QG8CDNE, both verified as complete replacements with consistent terminals and package.
Recommended
Legacy Design Maintenance
For products already in production using the MC9S08QG8CFFE, the priority is supply continuity rather than new design. NXP's product page documents the discontinuance and replacement product change notice; purchasing should secure last-time-buy quantities from DigiKey and Mouser (stock ships today while it lasts), then register with Rochester Electronics, which carries the MC9S08QG8CFFER licensed continuation. Engineering should qualify at least one pin-compatible alternate - MC9S08QG8CDTE or MC9S08QG8CDNE - on the same 16-QFN footprint so the PCB requires no re-spin. Per FindIC, these replacements keep performance parameters, terminals, and package consistent, requiring no layout modification.
Recommended
Recommended Products Summary
Engineering reference data for MC9S08QG8CFFE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08QG8CFFER | MC9S08QG8CDTE | MC9S08QG8CDNE | MC9S08QG4CFFE |
|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-QFN-EP (5x5 mm) | 16-QFN-EP (5x5 mm) - same | QFN-16 - same | QFN-16 - same | 16-QFN-EP (5x5 mm) - same |
| Core | S08, 8-bit | S08, 8-bit | S08, 8-bit | S08, 8-bit | S08, 8-bit |
| Bus Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Flash Memory | 8KB (8K x 8) | 8KB (8K x 8) | 8KB (8K x 8) | 8KB (8K x 8) | 4KB (4K x 8) |
| Lifecycle Status | End of Life | EOL; Rochester Electronics continuation | EOL family | EOL family | EOL family |
| In-Circuit Debug | BDM with breakpoints + BGND | Identical (same die) | Identical (same die) | Identical (same die) | Identical BDM system |
| PCB Modification Required | - | None (identical footprint) | None (per FindIC: full replacement) | None (per FindIC) | None; firmware must fit 4KB |
Key Differentiators
- Full 8KB Flash capacity in the smallest family footprint (vs MC9S08QG4CFFE)
- Licensed continuation availability (vs MC9S08QG8CDTE)
- Verified no-PCB-change replacement chain (vs MC9S08AC8CFDE)
Design Notes
The 16-QFN-EP (5x5 mm) package has an exposed pad that must be soldered to a grounded copper keepout on the PCB - do not leave it as an optical-only pad. Use an array of thermal vias under the pad to tie it to internal ground planes; this anchors the package mechanically against vibration and improves thermal relief. Follow the QFN package migration addendum in the S08QG8 datasheet (352-page document) when converting layouts originally designed for the older SOIC/DFN packages, since land-pattern geometry differs.
This part is End-of-Life per NXP, and its ETEI comparisons show that visually similar S08 parts (e.g., MC9S08AC8CFDE, MC9S08GT16ACFCER, MC9S08AC16MFDE) are NOT drop-in compatible - they come from different families and packages. Only substitute within the verified S08QG8 QFN-16 list on this page. Always verify the temperature/ordering-grade letter in the MPN suffix (F, D, etc.) before placing production orders, since grades differ in operating range and screening.
Estimated: budget the analog supply (VDDAD/VREFH) separately from digital VDD with local decoupling - typically a 100 nF ceramic at each supply pin plus a bulk 4.7 uF near the MCU - because ADC reference noise directly degrades conversion accuracy on the shared QFN pins. Keep the VSSAD/VREFL return path away from high-current switching grounds. Confirm exact recommended decoupling values from the manufacturer datasheet rather than this estimate.
Route the single-wire BKGD/MS debug pin (pin 3 area) to a 2.54 mm or 1.27 mm header footprint on every production board. Because the part is EOL, firmware re-flashing during last-time-buy validation and field debugging will be frequent, and the on-chip background debugging system is the only re-programming path. A 4-pin BDM header costs almost nothing and avoids destructive removal of QFN packages during development.
Compliance Information
Environmental quality page exists on the NXP product page but compliance values were not captured in the retrieved data; verify RoHS/REACH status on nxp.com/part/MC9S08QG8CFFE before procurement.
