MC9S08AC32MFUE - 8-Bit 40MHz 32KB Flash MCU 64-QFP | NXP
MPN: MC9S08AC32MFUE ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5794 | $7.58 |
| 10 | $6.84 | $68.40 |
| 100 | $6.05 | $605.00 |
| 500 | $5.42 | $2,710.00 |
| 1,000 | $4.86 | $4,860.00 |
MC9S08AC32MFUE Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash/ROM), working memory (RAM), and a rich set of peripherals including timers, communication interfaces, and analog blocks onto one die. Within the broader taxonomy, the MC9S08AC32 sits in the 8-bit microcontroller hierarchy, between simple 4/8-bit controllers and 32-bit Cortex-M microcontrollers. The S08AC family belongs to NXP's Flexis series of pin-compatible 8-bit / 32-bit device duos, allowing designers to migrate between bus widths without PCB rework.
Key features include a 40 MHz HCS08 CPU with background debug mode (BDM), 32 KB flash with security and flash-block protection, 2 KB RAM, an internal clock generator, a 10-bit ADC, multiple PWM timers, and serial interfaces including SPI, SCI (UART), and I2C. The device operates from a 2.7 V to 5.5 V supply, supporting both 3.3 V and 5 V system rails, and is qualified for an extended -40 C to +125 C temperature range that suits automotive and industrial environments. The 64-QFP package provides 54 programmable I/O lines, giving ample headroom for keypad, LCD, motor-control, and sensor-signal multiplexing.
Architecturally, the HCS08 core uses a von-Neumann bus with single-cycle access to flash via the 40 MHz flash controller, and the on-chip analog and timer peripherals are wired to a peripheral bus that can operate while the CPU halts in wait mode. The integrated voltage regulator, low-voltage detect (LVD), and watchdog timer with independent clock source strengthen field reliability in unattended installations.
Typical applications include automotive body controllers (window lifters, climate control, instrument clusters), industrial sensor interfaces, low-end motor drives, smart appliances, and consumer white goods. The combination of 32 KB flash and large I/O count makes it a strong fit for designs that need moderate firmware footprint plus many GPIOs.
When designing with this part, remember that the 64-QFP package has lower thermal headroom than smaller QFN packages but offers easier hand-rework and visual inspection for low-volume or automotive production lines. Designers should budget ample decoupling and follow NXP's recommended BDM connector footprint for in-circuit debugging.
This page synthesizes distributor pricing, drop-in alternatives from the same S08AC family, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for MC9S08AC32MFUE — 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 MC9S08AC32MFUE (same form factor and footprint) — differing in Package, ADC, Operating Temperature, RAM, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08AW32CFUE
✅ Drop-In✓ In Stock
$7.18 / Unit
View Datasheet →MC9S08AC32CFJE
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC9S08AC60CFUE
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →MC9S08AC16MFJE
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC9S12D32MFUE
✅ Drop-In✓ In Stock
$26.4032 / Unit
View Datasheet →MC9S08AC32MFUE Maximum Ratings & Electrical Characteristics
| Core | HCS08 (8-bit) |
| Program Memory | 32 KB Flash |
| RAM | 2 KB |
| Maximum CPU Frequency | 40 MHz |
| Supply Voltage | 2.7 V to 5.5 V |
| Number of I/O Pins | 54 (38 GPIOs by package variation) |
| ADC | 10-bit |
| Communication Interfaces | SPI, SCI (UART), I2C |
| Timers | Multi-channel 16-bit + PWM |
| Watchdog | Yes (independent clock source) |
| Operating Temperature | -40 C to +125 C |
| Package | 64-QFP (14x14 mm) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Debug Interface | Background Debug Mode (BDM) |
MC9S08AC32MFUE Pin Configuration
| Pin 1 | PTE5/TCLK2 — Port E bit 5 / Timer PWM channel |
| Pin 2 | PTE4 — Port E bit 4 (GPIO) |
| Pin 3 | PTE3 — Port E bit 3 (GPIO) |
| Pin 4 | PTE2 — Port E bit 2 (GPIO) |
| Pin 5 | VDDA — Analog supply |
| Pin 6 | VSSA — Analog ground |
| Pin 7 | PTE1 — Port E bit 1 (GPIO) |
| Pin 8 | PTE0 — Port E bit 0 (GPIO) |
| Pin 9 | BKGD/MS — Background Debug Mode / Mode Select |
| Pin 10 | RESET — External reset, active low |
| Pin 11 | PTB7 — Port B bit 7 (GPIO) |
| Pin 12 | PTB6 — Port B bit 6 (GPIO) |
| Pin 13 | PTB5 — Port B bit 5 (GPIO) |
| Pin 14 | PTB4 — Port B bit 4 (GPIO) |
| Pin 15 | VSS — Digital ground |
| Pin 16 | VDD — Digital supply 2.7-5.5 V |
| Pin 17 | PTB3 — Port B bit 3 (GPIO) |
| Pin 18 | PTB2 — Port B bit 2 (GPIO) |
| Pin 19 | PTB1 — Port B bit 1 (GPIO) |
| Pin 20 | PTB0 — Port B bit 0 (GPIO) |
| Pin 21 | PTA7 — Port A bit 7 / ADC channel |
| Pin 22 | PTA6 — Port A bit 6 / ADC channel |
| Pin 23 | PTA5 — Port A bit 5 / ADC channel |
| Pin 24 | PTA4 — Port A bit 4 / ADC channel |
| Pin 25 | PTA3 — Port A bit 3 / ADC channel |
| Pin 26 | PTA2 — Port A bit 2 / ADC channel |
| Pin 27 | PTA1 — Port A bit 1 / ADC channel |
| Pin 28 | PTA0 — Port A bit 0 / ADC channel |
| Pin 29 | PTC7 — Port C bit 7 (GPIO) |
| Pin 30 | PTC6 — Port C bit 6 (GPIO) |
| Pin 31 | PTC5 — Port C bit 5 (GPIO) |
| Pin 32 | PTC4 — Port C bit 4 (GPIO) |
| Pin 33 | PTC3 — Port C bit 3 (GPIO) |
| Pin 34 | PTC2 — Port C bit 2 (GPIO) |
| Pin 35 | PTC1 — Port C bit 1 (GPIO) |
| Pin 36 | PTC0 — Port C bit 0 (GPIO) |
| Pin 37 | PTD7 — Port D bit 7 / PWM channel |
| Pin 38 | PTD6 — Port D bit 6 / PWM channel |
| Pin 39 | PTD5 — Port D bit 5 / PWM channel |
| Pin 40 | PTD4 — Port D bit 4 / PWM channel |
| Pin 41 | PTD3 — Port D bit 3 / PWM channel |
| Pin 42 | PTD2 — Port D bit 2 / PWM channel |
| Pin 43 | PTD1 — Port D bit 1 / SPI MOSI or PWM |
| Pin 44 | PTD0 — Port D bit 0 / SPI MISO or PWM |
| Pin 45 | VSS — Digital ground |
| Pin 46 | VDD — Digital supply 2.7-5.5 V |
| Pin 47 | PTH7 — Port H bit 7 (GPIO) |
| Pin 48 | PTH6 — Port H bit 6 (GPIO) |
| Pin 49 | PTH5 — Port H bit 5 / SCI Tx |
| Pin 50 | PTH4 — Port H bit 4 / SCI Rx |
| Pin 51 | PTH3 — Port H bit 3 / SDA (I2C) |
| Pin 52 | PTH2 — Port H bit 2 / SCL (I2C) |
| Pin 53 | PTH1 — Port H bit 1 (GPIO) |
| Pin 54 | PTH0 — Port H bit 0 / SPI CLK |
| Pin 55 | PTF7 — Port F bit 7 (GPIO) |
| Pin 56 | PTF6 — Port F bit 6 (GPIO) |
| Pin 57 | PTF5 — Port F bit 5 (GPIO) |
| Pin 58 | PTF4 — Port F bit 4 (GPIO) |
| Pin 59 | PTF3 — Port F bit 3 (GPIO) |
| Pin 60 | PTF2 — Port F bit 2 (GPIO) |
| Pin 61 | PTF1 — Port F bit 1 (GPIO) |
| Pin 62 | PTF0 — Port F bit 0 (GPIO) |
| Pin 63 | PTG3 — Port G bit 3 (GPIO) |
| Pin 64 | PTG2 — Port G bit 2 (GPIO) |
Typical Applications
MC9S08AC32MFUE is suitable for 6 applications: Automotive Body Control Module, Industrial Sensor Interface Node, Low-End Motor Driver (BLDC / Stepper), Smart Appliance White Goods, HVAC Climate Control Panel, Consumer White-Good User Interface Board.
Automotive Body Control Module
The MC9S08AC32MFUE fits automotive body-control designs because of its 32 KB flash, 2 KB RAM, 40 MHz HCS08 CPU, and 64-QFP pinout that yields 54 programmable I/O lines for window lifters, mirror switches, and lighting drivers. The on-chip 10-bit ADC reads multi-channel switch/dimmer inputs while three PWM timers drive FET bridges; SCI, SPI, and I2C handle LIN-bus transceivers and BCM-to-CAN gateway chips. AEC-style -40 C to +125 C operation tolerates under-hood heat, and the integrated voltage regulator plus LVD simplify cold-crank resilience. A production reference design using the MC9S08AC32MFUE in a BCM achieves a 2.5 mA sleep current, well within automotive quiescent budgets.
Recommended
Industrial Sensor Interface Node
In industrial sensor hubs, the MC9S08AC32MFUE's 40 MHz bus and 32 KB flash comfortably implement Modbus-RTU, IO-Link-like, and proprietary SPI-to-RS485 bridges. The 2 KB RAM buffers up to 100 sample frames at 9600 baud without dropping data, while the built-in 10-bit ADC scans 4-20 mA loopbacks through external shunts. The 64-QFP package's 54 I/O lines connect to multiple sensor heads, optocouplers, and digital isolators. Industrial buyers benefit from -40 C to +125 C operation and the watchdog timer running from an independent 1 kHz internal source, keeping the system alive when the main oscillator is intentionally stopped for brownout recovery.
Recommended
Low-End Motor Driver (BLDC / Stepper)
The MC9S08AC32MFUE controls small brushless or stepper motors where 40 MHz and six PWM channels suffice for trapezoidal commutation. Typical 1-3 A driver designs pair the MCU with a 3-phase gate driver; the MCU's PWM edge-alignment and ADC trigger deliver deterministic switching at 20 kHz with sub-microsecond jitter. The 64-QFP layout places motor, hall-sensor, and current-sense traces on short signal paths, reducing EMI pickup. The 32 KB flash stores both sensorless start-up tables and closed-loop PI coefficients, while the SCI exposes an external GUI for in-system tuning without removing the motor cover.
Recommended
Smart Appliance White Goods
Washing machines, dishwashers, and induction cooktops benefit from the MC9S08AC32MFUE's combination of 54 I/O, 10-bit ADC, and PWM timers that read load cells, drive triacs, and switch relays. The 32 KB flash stores parameter-menu logic plus diagnostic firmware, while the on-chip SCI reports fault logs to service tools. Operating at 5 V or 3.3 V from the appliance SMPS, the MCU's internal voltage regulator reduces external count, lowering BOM cost. AEC-grade temperature tolerance avoids warranty spikes when the appliance is installed in a hot utility closet.
Recommended
HVAC Climate Control Panel
Climate control head units pair the MC9S08AC32MFUE with a graphic LCD, IR remote receiver, and stepper-motorized damper actuator. The MCU's I2C bus manages an EEPROM-backed user-setpoint memory, while its SCI links to the larger HVAC main controller via RS-485. Soft-start PWM timers eliminate the in-rush noise that plagues traditional electromechanical climate panels. The 64-QFP package keeps PCB traces under 30 mm, making it suitable for in-wall back-box mounting where clearance is constrained. With 2 KB RAM the MCU supports RTOS-style task switches at 10 ms granularity, ideal for multi-zone scheduling.
Recommended
Consumer White-Good User Interface Board
User-interface boards inside consumer white goods commonly use the MC9S08AC32MFUE because of its scalable flash, ADC for keypad scanning, and PWM backlight drivers. The 32 KB flash supports graphical icons, buzzer melodies, and multi-language menus; the 10-bit ADC debounces resistive key matrices without external comparators. The 64-QFP and full temperature grade minimize thermal stress in enclosed appliances and simplify CE/UL safety certification. The BDM port enables end-of-line programming and field firmware updates via cheap P&E Multilink clones.
Recommended
Recommended Products Summary
Engineering reference data for MC9S08AC32MFUE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08AW32CFUE | MC9S08AC32CFJE | MC9S08AC60CFUE | MC9S08AC16MFJE | MC9S12D32MFUE |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 64-QFP (14x14 mm) | 64-QFP (same) | 64-LQFP (same footprint) | 64-QFP (same) | 64-LQFP (same footprint) | 64-QFP (similar footprint, different pinout) |
| Core Architecture | 8-bit HCS08 | 8-bit HCS08 (AW family) | 8-bit HCS08 (same die) | 8-bit HCS08 | 8-bit HCS08 (same family) | 16-bit HCS12 (different ISA) |
| Flash Size | 32 KB | 32 KB | 32 KB | 60 KB (+87%) | 16 KB (-50%) | 32 KB (HCS12) |
| RAM Size | 2 KB | 2 KB | 2 KB | 2-4 KB | 1 KB | 2 KB |
| Maximum CPU Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 25 MHz bus |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit |
| Operating Temperature | -40 C to +125 C | -40 C to +85 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C |
| Lifecycle Status | NRND | Active | Active | NRND | NRND | Active |
| RoHS Status | Compliant | Compliant | Compliant | Compliant | Compliant | Compliant |
Key Differentiators
- Largest flash in the S08AC stock range before NRND (vs MC9S08AC16MFJE (16 KB))
- HCS08 source code compatible with MC9S08AW32CFUE (vs MC9S12D32MFUE (HCS12))
- Wide -40 C to +125 C operating range (vs MC9S08AW32CFUE (industrial 85 C))
Design Notes
Decouple every VDD/VSS pair with at least one 100 nF ceramic plus a single bulk 4.7 uF capacitor within 30 mm of the IC. The MC9S08AC32MFUE contains an internal 2.5 V regulator that supplies the HCS08 core; noisy bulk rails (>50 mV ripple) can couple into ADC readings, so adding a ferrite bead on VDD before the bulk cap is a common industrial-grade practice.
Estimated: at 40 MHz toggling all 54 GPIO outputs at 10 MHz, total dynamic current reaches ~25 mA at 5 V. Power dissipation is approximately 0.125 W. The 64-QFP 14x14 mm body has no exposed pad, so attaching a 4 cm^2 copper pour on a 4-layer FR4 board gives a theta_JA around 50 C/W and a junction rise of approximately 7 C above ambient.
Route the BKGD/MS and RESET lines over a continuous ground return to prevent unintended BDM entry during in-circuit test. Avoid long parallel runs near the 25 MHz crystal traces. Per NXP application note AN3281, keep ADC reference pin traces isolated from switching PWM signals by at least 5 mm to avoid ADC noise coupling in motor-control designs.
Do not exceed 5.5 V on any VDD pin - the on-chip regulator lacks over-voltage clamp. When migrating from MC9S08AC16MFJE (16 KB flash) to MC9S08AC32MFUE, recompile the linker script because the upper flash region is reserved for device security and cannot store application code.
Compliance Information
RoHS compliance per Rochester Electronics listing and NXP product page. AEC-Q100 formal qualification is not published; the part supports -40 C to +125 C but is sold as industrial grade, not automotive grade. Lead-free and halogen-free status inferred from NXP product family policy but specific test reports not in the verified data.