MC9S08AC128CFUE - 40MHz 128KB Flash 8-Bit MCU | NXP
MPN: MC9S08AC128CFUE ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.4113 | $7.41 |
| 10 | $7.4113 | $74.11 |
| 100 | $7.4113 | $741.13 |
| 500 | $7.4113 | $3,705.65 |
| 1,000 | $7.4113 | $7,411.30 |
MC9S08AC128CFUE Overview
An 8-bit microcontroller is a compact computer integrated on one semiconductor die, containing a CPU core, program Flash, RAM, peripherals, and input/output circuitry. The S08 architecture provides a deterministic, CISC-oriented control platform suitable for industrial equipment, consumer products, appliance controllers, and compact embedded systems. The AC family also provides pin-, peripheral-, and tool-compatibility pathways within the Flexis portfolio.
The MC9S08AC128CFUE combines 128 KB of internal Flash with up to 40 MHz operation. Verified comparison data identifies an enhanced HCS08-based S08 CPU, 8 KB internal RAM, a 16-channel 10-bit ADC, and 54 general-purpose I/O pins. Its 3.3 V or 5 V typical operating-supply options and 2.7 V to 5.5 V operating range support both 3.3 V and 5 V system designs.
The 64-QFP surface-mount package exposes substantially more interface options than smaller MCU packages, supporting multiple digital inputs and outputs alongside analog measurement. Arrow identifies the part as CISC architecture with an S08 core, 40 MHz maximum CPU frequency, an 8-bit data-bus width, and Flash program memory. The NXP product page reports that the AC series is part of the Flexis family and includes pin-compatible 8-bit and 32-bit device options.
Typical uses include appliance and motor-control logic, factory automation modules, environmental monitoring controllers, sensor interfaces, and compact industrial controls. Designers should preserve the QFP land pattern, confirm the exact peripheral multiplexing of each pin, and validate the replacement firmware against the target device before production release.
The principal design consideration is lifecycle risk: the NXP page labels this device end of life, while Arrow lists it as NRND. Existing embedded products may still use this MCU, but new production should confirm availability, migration options, and long-term supply before committing to the S08AC architecture.
This page consolidates verified manufacturer and distributor information, package constraints, lifecycle signals, and engineering-oriented selection guidance. It is intended to complement—not replace—the complete MC9S08AC128 Series Data Sheet with design-oriented context.
Drop-in alternatives for MC9S08AC128CFUE — 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 MC9S08AC128CFUE (same form factor and footprint) — differing in Package, RAM, Connectivity, RoHS Status, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08AC60CFUE
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →MC9S08AC32CFJE
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View Datasheet →MC9S08AW60CFUE
✅ Drop-In✓ In Stock
$8.1029 / Unit
View Datasheet →MC9S08AW48CFGER
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →MCF51AC256AVPUE
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$10.4 / Unit
View Datasheet →MCF51AG128CLF
✅ Drop-In✓ In Stock
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View Datasheet →MC9S08AC128CFUE Maximum Ratings & Electrical Characteristics
| CPU Architecture | CISC S08 core |
| Architecture Family | MC9S08AC128 / Flexis AC family |
| Maximum CPU Frequency | 40 MHz |
| Data Bus Width | 8 bit |
| Program Memory Type | Flash |
| Program Memory Size | 128 KB |
| Internal RAM | 8 KB |
| ADC Resolution | 10 bit |
| ADC Channel Count | 16 channels |
| General-Purpose I/O | 54 pins |
| Typical Operating Supply Voltage | 3.3 V or 5 V |
| Operating Supply Range | 2.7 V to 5.5 V |
| Minimum Operating Temperature | -40 °C |
| Maximum Operating Temperature | 85 °C |
| Package | 64-QFP, 14 mm x 14 mm |
| Mounting Type | Surface mount |
| Package Height | 2.4 mm maximum |
| Package Width | 14.1 mm maximum |
| Package Length | 14.1 mm maximum |
| RoHS Status | EU RoHS compliant |
| Automotive Qualification | No |
MC9S08AC128CFUE 14.1 mm maximum Pin Configuration Guide
Pin configuration for MC9S08AC128CFUE (14.1 mm maximum package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for MC9S08AC128CFUE.
Refer to the datasheet for full pin configuration.
Typical Applications
MC9S08AC128CFUE is suitable for 6 applications: Industrial Appliance Control, Sensor and Environmental Monitoring, Motor and Relay Control, Factory Automation Module, Consumer Product Interface Controller, Data Acquisition Front End.
Industrial Appliance Control
The MC9S08AC128CFUE fits appliance-control boards that need local decision-making, button and motor interfaces, and analog sensing without a high-cost processor. Its 40 MHz S08 core, 128 KB Flash, 8 KB RAM, and 54 general-purpose I/O pins provide room for state machines and peripheral coordination. A designer can connect sensors through the 16-channel 10-bit ADC and use the 64-QFP package to expose multiple control signals. The key trade-off is the end-of-life status, so the MCU is most appropriate for sustaining an existing product or a controlled legacy program rather than an unqualified new platform.
Recommended
Sensor and Environmental Monitoring
The MC9S08AC128CFUE is suitable for environmental monitoring when a design must combine several analog measurements with local actuator or communication logic. The 16-channel, 10-bit ADC supports inputs such as temperature, light, or analog sensor conditioning, while 54 general-purpose I/O can handle digital status signals, alarm outputs, and display-control lines. Its 2.7 V to 5.5 V operating range permits integration with 3.3 V and 5 V systems. Designers should budget ADC sampling, calibration, and noise-control time in firmware, and confirm that the chosen external sensors remain within the ADC input limits from the datasheet.
Recommended
Motor and Relay Control
The MC9S08AC128CFUE can serve as the supervisory controller in a motor, relay, or solenoid interface board when the system requires deterministic embedded sequencing. Its 40 MHz maximum CPU frequency and 54 general-purpose I/O allow timing tasks, switch-state monitoring, interlocks, and fault reporting to be implemented in local firmware. The MCU is not a high-power driver; external transistors, drivers, protection components, and isolation must be added where required. Validate inductive transients, supply sequencing, and thermal conditions independently of the microcontroller's -40 °C to 85 °C rating.
Recommended
Factory Automation Module
The MC9S08AC128CFUE is useful in compact factory automation modules that combine local I/O, analog monitoring, and embedded control without requiring a high-performance application processor. The 128 KB Flash supports protocol handling and control routines, while 8 KB RAM and the 40 MHz clock support responsive state management. A 64-QFP package makes numerous external connections available on a relatively compact board. Because the product is end-of-life, factory equipment upgrades should include an availability review and a migration path to a currently supported MCU family; otherwise, validate long-term availability and freeze equivalent parts.
Recommended
Consumer Product Interface Controller
The MC9S08AC128CFUE can be used in consumer products requiring a dedicated interface controller for buttons, indicators, sensors, and simple sequencing functions. Its 54 general-purpose I/O pins reduce the need for external expansion logic, and the 10-bit ADC supports product-level analog measurements. The 3.3 V and 5 V typical operating options make it flexible across embedded consumer platforms. Designers should keep the MCU within its 2.7 V to 5.5 V range, validate USB or communications transceivers separately, and confirm RoHS handling. Lifecycle risk remains the main concern for newly launched consumer hardware.
Recommended
Data Acquisition Front End
The MC9S08AC128CFUE can supervise a small data-acquisition front end when the system needs 16 analog channels, local processing, and multiple control outputs. The 10-bit ADC provides a practical resolution level for many cost-sensitive monitoring systems, and the 128 KB Flash can store calibration tables and control code. Use external buffering or multiplexing when signal integrity, sampling rate, or source impedance requires it; the ADC specifications and reference arrangement must come from the datasheet. The 64-QFP footprint supports separate analog and digital routing, but careful partitioning is still necessary to prevent digital switching noise from affecting measurements.
Recommended
Recommended Products Summary
Engineering reference data for MC9S08AC128CFUE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08AC60CFUE | MC9S08AC32CFJE | MC9S08AW60CFUE | MCF51AC256AVPUE | MCF51AG128CLF |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 64-QFP | 64-QFP | 64-QFP | 64-QFP | 64-QFP | 64-QFP |
| CPU Architecture | CISC S08 core | S08-related family device | S08-related family device | S08-related family device | Flexis 32-bit family device | Flexis 32-bit family device |
| Program Memory | 128 KB Flash | 60 KB Flash | 32 KB Flash | 60 KB Flash | 256 KB-class Flash; exact device value not verified | 128 KB-class Flash; exact device value not verified |
Key Differentiators
- Higher internal Flash capacity within the related MC9S08AC family (vs MC9S08AC60CFUE)
- Higher Flash capacity than the smaller MC9S08AC member (vs MC9S08AC32CFJE)
- Broader legacy control integration than a lower-memory S08 device (vs MC9S08AW60CFUE)
- 8-bit S08 compatibility instead of a 32-bit migration (vs MCF51AC256AVPUE)
Design Notes
Use the official MC9S08AC128 64-QFP land pattern and keep analog inputs away from high-current switching nets. The verified package is a 64-QFP measuring up to 14.1 mm by 14.1 mm with a 2.4 mm maximum height, so the footprint should be checked against the current manufacturer drawing rather than inferred from the generic QFP name. Route programming, reset, clock, and ground connections before placing optional peripherals.
Treat the 16-channel, 10-bit ADC as a sensitive analog subsystem. Keep the analog ground and digital return strategy consistent with the datasheet, place input conditioning close to the MCU pins, and avoid routing sensor traces beneath digital clocks or relay-control nets. The supplied sources do not include reference-circuit values, so capacitor selection, acquisition timing, and ADC settling must be taken from the manufacturer datasheet and application requirements.
Do not treat MC9S08AC60CFUE, MC9S08AC32CFJE, MC9S08AW60CFUE, MCF51AC256AVPUE, or MCF51AG128CLF as automatic drop-in replacements. The retrieved cross-reference results identify related products, but they do not prove identical pin multiplexing, voltage limits, clock behavior, memory mapping, or firmware compatibility. A replacement requires a complete package, pin, electrical, peripheral, and software review.
The verified operating range is 2.7 V to 5.5 V, with 3.3 V and 5 V typical supplies. Keep the MCU supply within that range across startup, load transients, and temperature extremes. The supplied data does not provide a complete current budget or capacitor table, so use the manufacturer DC characteristics and reference circuit for required decoupling, regulator headroom, and peripheral load analysis.
Lifecycle status must be treated as a design constraint. NXP labels MC9S08AC128CFUE end of life, while Arrow lists it as NRND. Existing products may be maintained with confirmed stock or an approved last-time-buy plan, but new designs should begin with a supported MCU migration. Document any equivalent firmware, hardware, test-fixture, and production-tool changes before replacing the legacy device.
Compliance Information
Arrow identifies the target as EU RoHS compliant and automotive status No. The supplied sources do not provide REACH, lead-free, halogen-free, or conflict-minerals status.
