MC908QB4CDWE - 8-bit 8MHz MCU 4KB Flash | NXP (Tape & Reel)
Référence : MC908QB4CDWE ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 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 Présentation
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.
Alternatives de remplacement direct pour MC908QB4CDWE — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MC908QB4MDWER
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MC908QB4VDWER
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MC908QB8DWER
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MC908QB4CDWE Valeurs maximales et caractéristiques électriques
| Core Processor | HC08 (M68HC08) |
| Core Size | 8-bit |
| Architecture | CISC |
| Fréquence d'horloge maximale | 8 MHz |
| Program Memory Size | 4KB (4K x 8) FLASH |
| RAM Size | 128 x 8 |
| Number of I/O | 13 |
| Tension d'alimentation | 3.3 V / 5 V |
| Boîtier / Format | 16-SOIC (0.295 in, 7.50 mm Width) |
| Type de montage | Surface Mount |
| Product Family | Nitron HC08Q (908QB4) |
| Packaging | Tape & Reel (T/R) |
| Nombre de broches | 16 |
| Program Memory Type | FLASH |
Guide de configuration des broches du MC908QB4CDWE 16-soic (0.295 in, 7.50 mm width)
Configuration des broches du MC908QB4CDWE (boîtier 16-soic (0.295 in, 7.50 mm width)). Ce circuit intégré numérique comprend des GPIO, des interfaces de communication (UART, SPI, I2C) et des broches d'alimentation. Consultez la fiche technique du fabricant pour les fonctions alternatives des broches et les options de configuration. Indispensable pour la conception de systèmes embarqués et la conception de circuits imprimés.
Aucune donnée de brochage détaillée disponible pour MC908QB4CDWE.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
MC908QB4CDWE convient pour 6 applications: 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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
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.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MC908QB4CDWE — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | 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 |
Principaux différenciateurs
- Extended temperature availability within the same footprint (vs MC908QB4MDWER)
- In-place code growth path (vs MC908QB8DWER)
- Dual-supply flexibility versus fixed-voltage legacy MCUs (vs older 68HC05 OTP parts)
Notes de conception
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.
Informations de conformité
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.
