MC908QB8MDWE - 8-bit HC08 MCU 8KB Flash 16-SOIC | NXP
MPN： MC908QB8MDWE ✓ 啟用中MC908QB8MDWE 概覽
What is an 8-bit microcontroller? An 8-bit microcontroller is a small computing system-on-chip that processes data 8 bits at a time and integrates a CPU, RAM, ROM/Flash, and peripherals into a single IC. The MC908QB8 belongs to the HC08 family - a CISC (Complex Instruction Set Computer) architecture descended from the M68HC05 lineage that emphasizes code density and ease of use for embedded control tasks. In the broader taxonomy: 8-bit MCU → microcontroller → embedded processor → semiconductor.
Key features of the MC908QB8MDWE include 8KB of on-chip Flash for application code and data, 256 bytes of RAM for stack and variables, and an internal clock generator supporting an 8MHz bus frequency. The device offers multiple GPIO pins, a 10-bit ADC module (typical for the HC08 family), timers for PWM and event capture, and an asynchronous serial communication interface (SCI) for UART-based networking. On-chip in-system programming (ISP) and in-circuit debugging (ICD) support simplifies firmware development and field updates.
The HC08 core uses a straightforward accumulator-based programming model with a small set of addressing modes that map cleanly to C compiler output. The Flash memory supports byte-erase and block-erase operations, allowing firmware upgrades without external programmer hardware. The wide 16-SOIC package provides robust mechanical leads suitable for hand-soldered prototypes, industrial control boards, and consumer appliances where leaded components are preferred over fine-pitch QFN alternatives.
Typical applications include small home appliances (coffee makers, microwave oven controllers), industrial sensor interfaces, automotive body electronics (non-safety subsystems), consumer device human-machine interfaces, and low-cost motor control boards. The combination of small footprint, mature toolchain (CodeWarrior HC08 / CodeWarrior 6.x), and proven long-term availability makes it popular in designs targeting 5-10 year production cycles.
When designing with this part, note that the 16-SOIC wide-body package occupies more board area than VQFN equivalents; reserve at least 100 mils of clearance around the leads for reliable hand-solder rework. Ensure firmware respects the Flash write endurance specification (typically 10,000 cycles per sector) when designing in-field update logic. Decoupling capacitors of 100nF plus a bulk 4.7uF should be placed within 5mm of the VDD pin to suppress switching noise from the internal clock multiplier.
This page synthesizes distributor pricing, drop-in HC08 family alternatives, and practical design notes not found in the standalone NXP datasheet.
直接替換替代品，適用於 MC908QB8MDWE — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MC908QB8MDWE （相同外形與佔位） — 差異在於 Package, Mounting Type, Data Bus Width, Flash Memory, Manufacturer.
MC908QB8CDWE
✅ 直接替換聯絡詢價
查看資料表 →MC908QB8MPE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC68HC908QB8MDWE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC908QB4MDWE
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →MC908QC8MDWE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC908QB8MDWE 最大額定值與電氣特性
| Manufacturer | NXP Semiconductors (formerly Freescale) |
| Product Family | M68HC08 / MC908QB8 |
| Core Architecture | HC08 (CISC, 8-bit) |
| Program Memory Size | 8 KB (8K x 8) Flash |
| CPU Speed | 8 MHz |
| 資料匯流排寬度 | 8-bit |
| 封裝 | 16-SOIC (Wide, 0.295 inch / 7.50mm) |
| 安裝類型 | Surface Mount |
| Communication Interfaces | SCI (UART) |
| In-Circuit Debug | Yes (HC08 ICD/BDM) |
MC908QB8MDWE 腳位配置
| 腳位 1 | IRQ — External interrupt request (also BDM data) |
| 腳位 2 | TCLK — Timer clock input / output compare |
| 腳位 3 | VDD — Positive supply voltage |
| 腳位 4 | OSC1 — Crystal/oscillator input |
| 腳位 5 | OSC2 — Crystal/oscillator output |
| 腳位 6 | VSS — Ground |
| 腳位 7 | RST — Reset input (active low) |
| 腳位 8 | PTB0 — GPIO port B bit 0 |
| 腳位 9 | PTB1 — GPIO port B bit 1 |
| 腳位 10 | PTB2 — GPIO port B bit 2 |
| 腳位 11 | PTB3 — GPIO port B bit 3 |
| 腳位 12 | PTB4 — GPIO port B bit 4 |
| 腳位 13 | PTB5 — GPIO port B bit 5 |
| 腳位 14 | PTB6 — GPIO port B bit 6 / TxD (SCI) |
| 腳位 15 | PTB7 — GPIO port B bit 7 / RxD (SCI) |
| 腳位 16 | VREFH — ADC voltage reference high (may share with VDD) |
典型應用
MC908QB8MDWE 適用於 7 應用s: Small Home Appliance Controllers, Industrial Sensor Interface Boards, Automotive Body Electronics (Non-Safety), Consumer Device Human-Machine Interfaces (HMI), Low-Cost BLDC / Stepper Motor Control Boards, Smart Sensor / IoT Edge Nodes (Wired), Educational / Hobbyist Embedded Platforms.
Small Home Appliance Controllers
The MC908QB8MDWE fits small home appliance controllers because its 8 KB Flash holds typical coffee maker, microwave UI, or toaster oven firmware while the 16-SOIC wide package survives hand-soldered assembly lines and field repair. With the SCI peripheral it can drive a UART-attached display module or communicate with a sensor front-end for temperature/humidity monitoring. Designers benefit from the HC08 CISC instruction set's code density, which keeps routine lookup-table-heavy control code compact. Low unit cost at 1,000-piece volumes directly targets the consumer appliance bill-of-materials ceiling.
推薦
Industrial Sensor Interface Boards
In industrial sensor interface boards the MC908QB8MDWE serves as a low-cost data aggregator: the on-chip 10-bit ADC reads analog sensor channels, the SCI forwards formatted frames to a host PLC or gateway, and the 8 MHz HC08 core handles simple linearization and threshold detection. The wide 16-SOIC package handles factory-floor thermal stress and vibration better than fine-pitch QFN alternatives. Pairing with external RS-485 transceivers extends the SCI to industrial multi-drop buses. Long-term NXP lifecycle support (5-10+ year production) is critical for industrial customers who cannot redesign every 2 years.
推薦
Automotive Body Electronics (Non-Safety)
Within automotive body electronics - non-safety subsystems such as interior lighting, seat controller nodes, or mirror adjust - the MC908QB8MDWE provides a proven 8-bit platform with LIN-bus-ready SCI peripheral and adequate timers for PWM-driven actuator control. The 16-SOIC wide package is automotive-friendly for service-friendly PCBs. Note that this part is NOT AEC-Q100 qualified; for safety-critical ECUs a dedicated automotive MCU is mandatory. Use this part on seats, lighting, or HVAC damper nodes where cost dominates over qualification level.
推薦
Consumer Device Human-Machine Interfaces (HMI)
The MC908QB8MDWE controls consumer HMI panels where its HC08 core scans button matrices, drives 7-segment or LCD displays via GPIO, and serializes key events to a host CPU. Typical HMI tasks - debouncing, mode rotation, LED fading - fit inside 8 KB Flash comfortably. The wide SOIC package is well-suited to through-hole repair procedures common in consumer service centers. Low quiescent current during sleep states preserves battery life in remote-control or wall-switch SKUs.
推薦
Low-Cost BLDC / Stepper Motor Control Boards
The MC908QB8MDWE drives low-cost BLDC and stepper motor control boards where the HC08 core generates PWM via its 16-bit timers, the ADC samples phase current or back-EMF, and the SCI exposes a tuning/debug interface to a host PC. 8 KB Flash holds sensorless start-up routines, commutation tables, and PI loop code for small fans or pumps. Designers benefit from the deterministic interrupt latency of the HC08 architecture, which is critical for sensorless BLDC start-up algorithms.
推薦
Smart Sensor / IoT Edge Nodes (Wired)
Wired IoT edge nodes - factory-floor environmental monitors, agriculture soil probes, or building automation sensors - benefit from the MC908QB8MDWE's SCI peripheral for RS-485 multi-drop networking. 8 KB Flash holds MODBUS RTU stack fragments and basic calibration tables; the 8 MHz core handles polling without DMA. Wide SOIC package with hand-solderable leads suits small-batch industrial gateways and field retrofits where fine-pitch QFN rework would be impractical.
推薦
Educational / Hobbyist Embedded Platforms
The MC908QB8MDWE remains popular in educational and hobbyist embedded platforms because the wide SOIC package fits standard 0.1-inch pitch breadboard adapters and through-hole perfboards. Students learning C programming for 8-bit cores benefit from the HC08's simple accumulator model and CodeWarrior IDE debugging experience. Many university embedded systems courses still reference the MC908QB8 family as a teaching vehicle for register-level programming fundamentals before students move on to ARM Cortex architectures.
推薦
推薦產品摘要
工程參考資料，適用於 MC908QB8MDWE — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MC908QB8CDWE | MC908QB8MPE | MC68HC908QB8MDWE | MC908QB4MDWE | MC908QC8MDWE |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors (Freescale legacy) | NXP Semiconductors | NXP Semiconductors |
| Package | 16-SOIC (Wide, 7.50mm) | 16-SOIC (Wide) - same | 16-SOIC (Wide) - same | 16-SOIC (Wide) - same | 16-SOIC (Wide) - same | 16-SOIC (Wide) - same |
| Program Memory (Flash) | 8 KB | 8 KB | 8 KB | 8 KB | 4 KB (-50%) | 8 KB |
| CPU Core | HC08 CISC, 8-bit | HC08 CISC, 8-bit | HC08 CISC, 8-bit | HC08 CISC, 8-bit | HC08 CISC, 8-bit | HC08 CISC, 8-bit |
| Maximum CPU Speed | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| Temperature Grade | Industrial (M suffix) | Commercial (C suffix) | Industrial (M suffix) | Industrial | Industrial (M suffix) | Industrial (M suffix) |
| ADC | 10-bit on-chip | 10-bit on-chip | 10-bit on-chip | 10-bit on-chip | 10-bit on-chip | 10-bit on-chip (more channels) |
| SCI (UART) | 1 x SCI | 1 x SCI | 1 x SCI | 1 x SCI | 1 x SCI | 1 x SCI + extras |
主要差異化特點
- Wide-body 16-SOIC improves hand-soldered serviceability (對比Generic QFN-packaged HC08 alternatives)
- Industrial temperature grade at same SOIC footprint (對比MC908QB8CDWE)
- Mature HC08 toolchain ecosystem (對比Newer ARM Cortex-M0 MCUs)
設計說明
Estimated: at 8 MHz VDD=5V with typical HC08 active current around 15 mA, the MC908QB8MDWE dissipates roughly 75 mW continuous. Add a 100 nF ceramic decoupling capacitor within 5 mm of the VDD pin and a bulk 4.7 uF tantalum or aluminum-polymer capacitor near the regulator output to suppress transient load. For low-power standby modes the HC08 STOP instruction plus internal oscillator settling time defines wake-up latency - consult the device datasheet for exact STOP recovery cycles.
Do not substitute the wide-body 16-SOIC pinout for the narrow-body SO-16 - the 7.50 mm wide package has 1.27 mm pitch across the same 16 pins but a larger body that will collide with adjacent narrow-SOIC footprints. The MC908QB8MDWE package suffix 'WE' (wide SOIC) must be preserved when ordering. Also note that the 'M' suffix in 'MDWE' indicates industrial temperature range; if a commercial-only design is acceptable, ordering the 'CDWE' variant can reduce unit cost.
Place the external crystal or ceramic resonator within 5 mm of the OSC1/OSC2 pins and route the traces over a continuous ground plane. Shield the crystal traces with grounded copper on both sides to prevent coupling of switching noise into the clock network. Keep the BDM (background debug mode) interface pins routed to a 2x5 or 2x3 header accessible at the board edge for in-circuit debugging - the HC08 ICD protocol uses these pins and a programming tool can recover locked devices through them.
合規資訊
Detailed RoHS/REACH and lead-free status are device- and lot-dependent for legacy HC08 wide-SOIC parts; confirm with the supplier's certificate of conformance at order time. The part is not AEC-Q100 qualified and should not be used in safety-critical automotive ECUs.
