MC908QB4CDWE - 8-bit 8MHz MCU 4KB Flash | NXP (Tape & Reel)
料号： MC908QB4CDWE ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $4.37 | $4.37 |
| 10 | $4.15 | $41.50 |
| 100 | $3.93 | $393.00 |
| 500 | $3.71 | $1,855.00 |
| 1,000 | $3.5 | $3,500.00 |
MC908QB4CDWE 概述
An 8-bit MCU is a single-chip computer whose CPU processes data 8 bits at a time. Within the system hierarchy, the MC908QB4 belongs to the NXP (formerly Freescale/Motorola) HC08 family, a CISC-architecture descendant of the classic 68HC05, positioned under the microcontroller category for cost-sensitive embedded control. The Nitron designation refers to NXP's entry-level Flash MCUs targeting low-pin-count, high-volume applications.
Key features of the MC908QB4CDWE include the 4KB in-system-programmable Flash program memory that eliminates external EPROM/OTP programming, 13 general-purpose I/O lines for direct sensor and actuator interfacing, and dual 3.3V/5V supply operation that eases migration between legacy 5V systems and modern 3.3V rails. The 16-pin SOIC wide-body footprint keeps PCB area small while remaining hand-solderable for prototyping.
Technically, the device executes the HC08 instruction set, an enhanced and fully upward-compatible expansion of the 68HC05 core with an indexed addressing model and stack pointer relative addressing. Peripherals typical of the QB4 family include an 8-bit timer module, analog capabilities, and oscillator options suited to low-cost resonator or RC clocking, allowing deterministic low-jitter timing for small control loops.
Typical applications include small appliance control, battery chargers, lighting and fan control, and simple industrial sensing nodes where a compact 8-bit MCU with Flash memory reduces bill-of-materials cost.
Design consideration: verify supply-voltage choice (3.3V versus 5V) early, since I/O thresholds and timing margins differ; decouple VDD with 0.1uF ceramic capacitors placed close to the package pins.
This page synthesizes distributor pricing, family drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替换替代料： MC908QB4CDWE ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： MC908QB4CDWE （相同外形与封装尺寸） ——差异在于 Package, Program Memory Size, RAM Size, Architecture, Packaging.
快速对比工具——选择替代料号进行并排对比：
该产品暂无直接替换替代料。
请求替代料MC908QB4CDWE 最大额定值与电气特性
| Core Processor | HC08 (M68HC08) |
| Core Size | 8-bit |
| Architecture | CISC |
| 最大时钟频率 | 8 MHz |
| Program Memory Size | 4KB (4K x 8) FLASH |
| RAM Size | 128 x 8 |
| Number of I/O | 13 |
| 电源电压 | 3.3 V / 5 V |
| 封装 / 外壳 | 16-SOIC (0.295 in, 7.50 mm Width) |
| 安装类型 | Surface Mount |
| Product Family | Nitron HC08Q (908QB4) |
| Packaging | Tape & Reel (T/R) |
| 引脚数 | 16 |
| Program Memory Type | FLASH |
MC908QB4CDWE 16-soic (0.295 in, 7.50 mm width) 引脚配置指南
MC908QB4CDWE（16-soic (0.295 in, 7.50 mm width) 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： MC908QB4CDWE.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MC908QB4CDWE 适用于 6 应用s: Small Appliance Control, Battery Chargers, Lighting and Fan Control, Industrial Sensing Nodes, Legacy 5V System Maintenance, Smart Home Sensor Accessories.
Small Appliance Control
The MC908QB4CDWE fits small appliance controllers such as coffee makers, blenders, and rice cookers because its 4KB Flash holds compact control state machines while 13 I/O lines directly drive relays, buttons, and LEDs at 5V. The 8 MHz HC08 core provides deterministic scan-loop timing without an RTOS, and the 16-SOIC package minimizes controller footprint on cost-driven single-sided layouts. Dual 3.3V/5V operation lets the same firmware platform migrate to newer 3.3V display boards. Flash memory enables late-stage firmware updates without mask charges, a key cost benefit at appliance production volumes where code often changes after safety certification.
推荐
Battery Chargers
In NiMH and Li-ion charger boards, the MC908QB4CDWE supervises charge termination logic by reading voltage and temperature sense dividers through its I/O and controlling charge current via PWM output. The 8 MHz bus executes peak-voltage-detection and delta-T algorithms deterministically, while 5V operation directly interfaces with common charger front-ends without level shifting. Its 128-byte RAM is sufficient for state-machine variables and filtering buffers. The 16-SOIC (7.50 mm) package survives typical charger thermal environments, and the Flash program memory supports charger-profile tuning at the end of production, which is routine when cell vendors revise specifications.
推荐
Lighting and Fan Control
The QB4's timer-based PWM output makes the MC908QB4CDWE well suited to dimmable LED drivers and multi-speed ceiling-fan controls. The 8 MHz HC08 core generates stable PWM frequencies without software jitter, and 13 I/O lines accommodate triac/MOSFET drive plus user interface buttons simultaneously. Its 5V supply integrates with legacy transformer-based lighting power supplies, while 3.3V operation supports newer electronic ballast designs. The 16-SOIC wide-body package offers manageable hand assembly for service replacement in installed fixtures, and Flash memory lets OEMs ship regional dimming-curve variants from one hardware BOM, reducing SKU proliferation.
推荐
Industrial Sensing Nodes
For simple industrial sensors such as limit-switch monitors, temperature transmitters, and level detectors, the MC908QB4CDWE provides a rugged 8-bit solution with enough Flash for linearization tables and 13 I/O for sensor front-ends and 4-20 mA style outputs. The HC08 CISC core runs fixed-point conversion math deterministically at 8 MHz, and 5V operation gives robust noise margins in electrically noisy factory environments. The 16-SOIC surface-mount package reflows onto standard industrial PCBs, and its long field history simplifies safety-case documentation. Extended-temperature family variants cover panel-mounted enclosures that exceed commercial ambient limits.
推荐
Legacy 5V System Maintenance
Many installed 68HC05/68HC08-based products require continued production of replacement controller boards. The MC908QB4CDWE is a natural sustenance choice because it keeps 5V I/O compatibility, a familiar HC08 toolchain, and the standard 16-SOIC footprint used across many legacy designs. Firmware written for HC08 ports with minimal change, avoiding the cost and requalification of an ARM-based redesign. Rochester Electronics continues to supply the exact MC908QB4CDWE as an authorized aftermarket source, so maintenance programs can source the original part number when new-production NXP stock narrows, extending product lifecycles safely.
推荐
Smart Home Sensor Accessories
Low-cost smart-home accessories such as door/window sensors, PIR alarm modules, and IR remote receivers use the MC908QB4CDWE where its 128-byte RAM and 4KB Flash implement protocol encoding and simple RF-link framing. The 8 MHz core timestamps edge events precisely for IR decode, and deep low-power standby behavior of the HC08Q family extends coin-cell life in battery accessories. Operation at 3.3V matches modern sensor and radio modules without level shifters, and the small 16-SOIC package fits slim plastic enclosures. Flash memory supports per-customer protocol customization late in manufacturing for private-label product lines.
推荐
推荐产品汇总
工程参考数据： MC908QB4CDWE ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | MC908QB4MDWER | MC908QB4VDWER | MC908QB8DWER |
|---|---|---|---|---|
| Package | 16-SOIC (0.295 in, 7.50 mm Width) | 16-SOIC (7.50 mm) - same | 16-SOIC (7.50 mm) - same | 16-SOIC (7.50 mm) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Program Memory | 4KB (4K x 8) FLASH | 4KB FLASH | 4KB FLASH | 8KB FLASH |
| Max Clock | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| I/O Count | 13 | 13 | 13 | 13 |
| Supply Voltage | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V |
关键差异点
- Extended temperature availability within the same footprint （对比 MC908QB4MDWER)
- In-place code growth path （对比 MC908QB8DWER)
- Dual-supply flexibility versus fixed-voltage legacy MCUs （对比 older 68HC05 OTP parts)
设计说明
Decouple VDD with a 0.1uF ceramic capacitor placed within a few millimeters of the supply pin, plus a 4.7uF to 10uF bulk capacitor near the board entry point. The MC908QB4 operates from either 3.3V or 5V, so confirm which rail feeds flash programming routines; erasing/programming margins can differ from read-mode margins. Estimated: at 8 MHz the HC08 core draws only a few milliamps, so supply design is dominated by external load circuitry rather than the MCU itself.
Keep the reset line clean: the HC08 QB family relies on a proper reset for flash security and mode entry. Avoid long reset traces near switching loads, and add a 10k pull-up. When migrating between the C, V, and M temperature grades, re-verify crystal or resonator tolerance across the full temperature span, since clock accuracy affects the timer-based PWM duty resolution. Ensure unused I/O are configured as outputs low or inputs with pull-ups to prevent floating-node EMI.
Use the 16-SOIC (7.50 mm) land pattern per IPC SOIC wide-body dimensions and give the oscillator traces a short, direct route with guard ground when using a crystal. Separate the analog sense routing from PWM/triac drive traces to keep switching noise out of threshold comparisons. Because the MCU is usually the only digital device on cost-driven boards, a solid ground pour under the controller region is usually sufficient - no elaborate multilayer split is needed for this 8 MHz design.
合规信息
Compliance status not stated in provided web data; verify against the NXP product page and material declaration reports before export-controlled or green-procurement programs.
