MC908GR32ACFUE - 8-bit HC08 MCU, 32KB Flash, 64-QFP | NXP
MPN: MC908GR32ACFUE ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.9 | $7.90 |
| 10 | $7.15 | $71.50 |
| 100 | $6.4 | $640.00 |
| 500 | $5.8 | $2,900.00 |
| 1,000 | $5.25 | $5,250.00 |
MC908GR32ACFUE Overview
An 8-bit microcontroller is a single-chip computing device whose CPU processes data in 8-bit words. Within the embedded-systems hierarchy, the MC908GR32 sits in the microcontroller (MCU) category under the broader HC08 architecture family from Freescale Semiconductor, now part of NXP Semiconductors. MCUs of this class combine processor core, program memory, data RAM, timers, and I/O peripherals on one die, replacing multi-chip processor-plus-support-logic designs.
Key features include 32KB of in-system-programmable FLASH program memory for firmware field updates, 1.5K x 8 bytes of on-chip RAM, 53 I/O pins that give exceptional connectivity for a small 8-bit controller, and an internal oscillator option that reduces bill-of-materials cost and board area. The 8 MHz bus speed is sufficient for control loops, serial communication, and human-machine interface tasks.
Architecturally, the HC08 core uses an object-compatible enhancement of the HC05 CISC instruction set with stack-pointer-based indexed addressing, low-power wait and stop modes, and a watchdog. The G-series integration adds peripherals typical of the family, and the F-suffix package code denotes the 64-lead QFP in a 14x14 mm body. The AC grade supports operation across the industrial temperature range, and the trailing E denotes lead-free, RoHS3-compliant packaging.
Typical applications include industrial control panels, motor control and appliance boards, automotive body modules, building automation nodes, and legacy embedded-system maintenance where the HC08 ecosystem and existing firmware must be preserved. The 53 I/O count makes it particularly suited to keypads, LED/LCD driving, and relay-intensive boards.
A key design consideration is clock planning: the internal oscillator is convenient, but if accurate serial baud rates or precise timing are required, verify the internal oscillator tolerance or use the external clock option per the manufacturer datasheet.
This page synthesizes distributor pricing tiers, same-family drop-in alternatives, and practical design notes not found in the manufacturer datasheet, making it a one-stop reference for sourcing and design-in of the MC908GR32ACFUE.
Drop-in alternatives for MC908GR32ACFUE — 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 MC908GR32ACFUE (same form factor and footprint) — differing in RAM Size, Program Memory Size, Core Processor, Package, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC908GZ32CFUE
✅ Drop-In📋 Reference alternative (not in catalog)
MC908GZ32VFUE
✅ Drop-In✓ In Stock
$5.15 / Unit
View Datasheet →MC908GR16VFAE
✅ Drop-In📋 Reference alternative (not in catalog)
MC908GR8BMFA
✅ Drop-In📋 Reference alternative (not in catalog)
MC908GR32ACFUE Maximum Ratings & Electrical Characteristics
| Core Processor | HC08 (8-bit CISC) |
| Core Size | 8-bit |
| Speed | 8 MHz |
| Program Memory Size | 32KB (32K x 8) |
| Program Memory Type | FLASH |
| RAM Size | 1.5K x 8 |
| Number of I/O | 53 |
| Oscillator Type | Internal |
| Package / Case | 64-QFP (14x14 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tray |
| RoHS Status | ROHS3 Compliant |
| Lead Free Status | Lead Free |
MC908GR32ACFUE 64-qfp (14x14 mm) Pin Configuration Guide
Pin configuration for MC908GR32ACFUE (64-qfp (14x14 mm) 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 MC908GR32ACFUE.
Refer to the datasheet for full pin configuration.
Typical Applications
MC908GR32ACFUE is suitable for 6 applications: Industrial Control Panels, Appliance Control Boards, Building Automation Nodes, Legacy Embedded System Maintenance, Motor Control and Relay Drivers, Sensor and Instrumentation Front Ends.
Industrial Control Panels
The MC908GR32ACFUE fits industrial control panels because its 53 general-purpose I/O lines and 8 MHz HC08 core cover the pin-heavy demands of pushbuttons, selector switches, relay drivers, and status LEDs on a single controller. According to the verified specifications, the 32KB FLASH supports structured control firmware with in-system reprogramming for field updates, while the 1.5K x 8 RAM holds state machines and communication buffers. The internal oscillator option removes crystal cost from cost-sensitive panel builds. Place the MCU in the main control card between the input-conditioning stage and the relay/SSR driver stage; the deterministic 8-bit CISC core executes simple loop control without RTOS overhead. The main trade-off versus a modern 32-bit MCU is peripheral sophistication, but for discrete-logic panels the GR32 reduces component count and firmware complexity while keeping the HC08 ecosystem's proven reliability.
Recommended
Appliance Control Boards
Home and commercial appliance boards (washers, dishwashers, cooktops) are a classic HC08 G-series application: they need many I/O for keypads, displays, load switching, and motor relays, exactly matching the MC908GR32ACFUE's 53 I/O count. The 32KB FLASH accommodates user-interface logic, safety interlocks, and communication routines without external memory, and the internal oscillator trims the bill of materials for high-volume manufacturing. In a typical topology the MCU sits on the power/sense board, reading thermistor or ADC inputs and driving triac or relay loads through isolation. The 8 MHz bus clock is sufficient for button scanning at millisecond periods and slow control loops. Because appliance platforms run for a decade or more, the availability of RoHS3-compliant, lead-free HC08 stock through authorized aftermarket channels (Rochester Electronics) supports long-term serviceability of existing designs.
Recommended
Building Automation Nodes
The MC908GR32ACFUE suits building-automation nodes such as damper controllers, occupancy sensor hubs, and HVAC zone controllers, where the design needs moderate compute, many discrete I/O, and low unit cost. The verified spec set - 8-bit HC08 core at 8 MHz, 32KB FLASH, 1.5K x 8 RAM, 53 I/O, internal oscillator - covers networked node firmware including serial links to gateway controllers. The 64-QFP (14x14 mm) surface-mount package provides enough pins for direct LED/LCD drive and multi-point input sensing without port expanders, shortening the board design cycle. FLASH-based program memory allows field firmware updates during commissioning, an important operational benefit across installed estates. Designers should validate timing accuracy of the internal oscillator if baud-rate-critical serial communication is used, adding an external clock where the datasheet tolerance is insufficient for the chosen link speed.
Recommended
Legacy Embedded System Maintenance
A primary modern use of the MC908GR32ACFUE is sustaining engineering for installed HC08-based products: when a board using this MCU fails or a production line needs a spares pool, sourcing the exact ordering code preserves binary-compatible firmware with zero redesign. The verified data confirms DigiKey same-day shipping, Rochester Electronics aftermarket supply, and Micro-Semiconductor.com stock (5784 pcs reported), giving multiple continuity channels. Because the HC08 core is object-compatible across the family, drop-in boards can be rebuilt with the identical 64-QFP footprint and no software changes. Procurement teams should buy in tray quantities and request date codes and authenticity verification when ordering from independent distributors. This continuity strategy is far cheaper than porting firmware to a modern MCU, requalifying the board, and re-certifying the end product.
Recommended
Motor Control and Relay Drivers
Small motor and actuator control applications benefit from the MC908GR32ACFUE's combination of timer resources, 53 I/O lines, and 8 MHz deterministic core. Typical duties include generating PWM drive through external transistor or MOSFET stages, sequencing contactors, monitoring limit switches, and implementing stall/overcurrent shutdown logic. The 32KB FLASH holds closed-loop control code plus diagnostic logging, while the 1.5K x 8 RAM buffers fault histories. Using the HC08's wait and stop low-power modes, standby consumption in idle states can be reduced per the family architecture described in NXP documentation. Layout-wise, keep the MCU ground reference star-connected away from motor switching return paths and use opto-isolation between the controller and power stage. The internal oscillator's tolerance is acceptable for open-loop PWM duty control, but verify it against the datasheet before using it for commutation timing.
Recommended
Sensor and Instrumentation Front Ends
The MC908GR32ACFUE serves as the processing element in low-cost instrumentation front ends that digitize sensor arrays and report over serial links. Paired with external serial ADCs such as the TLC549 or TLV2545, the HC08 core handles conversion sequencing, digital filtering, scaling, and threshold alarms across many channels, leveraging the 53 I/O for channel multiplexing and status signaling. The 8 MHz bus speed supports kHz-rate sampling loops with headroom for filtering arithmetic, and the 32KB FLASH retains calibration tables and compensation curves in-field programmable form. In bench or panel instruments, the 64-QFP 14x14 mm package mounts cleanly on standard PCB processes, and the internal oscillator simplifies single-board designs. For precision timing requirements, consult the NXP datasheet regarding oscillator tolerance and the external clock input option before locking the architecture.
Recommended
Recommended Products Summary
Engineering reference data for MC908GR32ACFUE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC908GZ32CFUE | MC908GZ32VFUE | MC908GR16VFAE | MC908GR8BMFA |
|---|---|---|---|---|---|
| Package | 64-QFP (14x14 mm) | 64-QFP | 64-QFP | 64-QFP | 64-QFP (verify pin count) |
| Brand | NXP Semiconductors (Freescale) | NXP Semiconductors (Freescale) | NXP Semiconductors (Freescale) | NXP Semiconductors (Freescale) | NXP Semiconductors (Freescale) |
| Core / Architecture | HC08 8-bit CISC | HC08 8-bit CISC | HC08 8-bit CISC | HC08 8-bit CISC | HC08 8-bit CISC |
| Program Memory | 32KB (32K x 8) FLASH | 32KB FLASH | 32KB FLASH | 16KB FLASH (-50%) | 8KB FLASH (-75%) |
| Max Speed | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
Key Differentiators
- Highest I/O count in its class (vs MC908GZ32CFUE)
- Full 32KB FLASH in the GR sub-family (vs MC908GR16VFAE)
- Lower cost for simple firmware (vs MC908GR32ACFUE (self-baseline))
Design Notes
The 64-QFP (14x14 mm) body requires a footprint with 0.65 mm-pitch gull-wing lands; verify the exact land pattern from the NXP datasheet mechanical drawing (footprint FC-64 style typical of the HC08 G-series) before routing. Because 53 of 64 pins serve as I/O, assign port functions first and route the highest-frequency or noisiest signals (serial links, PWM outputs) with short direct traces. Provide a solid ground plane on layer 2 and place a 100 nF ceramic decoupling capacitor at each supply pin pair plus a bulk 10 uF near the regulator.
Do not assume cross-family pin compatibility within the HC08 G-series. The GR and GZ sub-families both ship 32KB FLASH parts in QFP packages, but peripheral multiplexing and register maps differ; the Utmel comparison data confirms they are separate sub-families. Before substituting MC908GZ32CFUE or MC908GZ32VFUE for the GR32, overlay the two datasheet pinout tables pin-by-pin and re-run the firmware regression suite, especially interrupt vector assignments and timer/serial register addresses.
The internal oscillator is convenient for cost-reduced designs, but its frequency tolerance over temperature and process must be checked against the NXP datasheet if the SCI serial port runs at high baud rates; a timing error beyond about 3% total can break asynchronous framing. Where communications matter, either use the external clock/crystal option per the family reference manual or derate the chosen baud rate. Also route the oscillator/external clock traces away from relay and motor-drive return currents.
Confirm the supply voltage range for the AC-grade suffix directly from the NXP datasheet electrical characteristics before finalizing the power tree; HC08 G-series parts of this era commonly target a nominal 5V rail, and running outside the verified window risks brown-out resets or flash-programming errors. Add local decoupling and consider a supervisor/reset IC on the reset pin for reliable power-up in electrically noisy industrial environments.
Compliance Information
Distributor data (iccomponents-distributor.com) lists Lead Free Status / RoHS Status as ROHS3 Compliant. REACH, halogen-free, and conflict-minerals status should be requested from NXP compliance documentation.