MC68HC908GR8CDW - 8-Bit HC08 MCU 7.5KB Flash 8MHz 28-SOIC | NXP
Référence : MC68HC908GR8CDW ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $4.33 | $4,33 |
| 10 | $3.62 | $36,20 |
| 100 | $2.78 | $278,00 |
| 500 | $2.41 | $1 205,00 |
| 1 000 | $2.1 | $2 100,00 |
MC68HC908GR8CDW Présentation
A microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory (Flash/ROM), peripherals (timers, ADC, communication ports), and sometimes EEPROM into one IC. Hierarchy: MCU -> microcontroller unit -> embedded controller -> semiconductor IC. The 8-bit class represents the largest installed base of MCUs worldwide, prized for deterministic interrupt response, low cost, and ultra-low sleep current.
Key features of the MC68HC908GR8CDW include 7.5KB of on-chip Flash memory (7.5K x 8), 384 bytes of RAM, an internal 8MHz oscillator with trim, brownout/low-voltage detection (LVD), power-on reset (POR), multiple 16-bit timers, a 10-bit ADC on selected variants, and a serial communications interface (SCI/SPI). The 28-SOIC wide-body package (0.295 inch / 7.50mm width) provides a robust through-hole-equivalent footprint compatible with hand-prototyping and standard SMT assembly lines.
Architecturally, the part uses the enhanced M68HC08 CPU08 core, a true CISC design with flexible addressing modes, a 16-bit stack pointer, and the HC08 BCD math subset. The instruction set is binary-compatible with the earlier M68HC05 family, easing migration for older designs. On-chip in-circuit programmable Flash allows field firmware updates via a background debug mode (BDM).
Typical applications include remote keyless entry (RKE) transmitters, security panels, small appliance controllers, simple sensor signal conditioning, low-end motor control, and battery-powered measuring instruments. The 3.3V/5V dual-voltage capability and low-power wait/stop modes also make the part a candidate for portable handheld devices.
Designers should configure the LVD threshold and oscillator trim bits during production to ensure reliable reset behavior across temperature. Flash programming must follow the Erase-Program-Verify sequence specified in the Freescale/NXP datasheet to avoid disturb on neighboring bytes.
This page synthesizes distributor pricing, drop-in NXP same-family alternatives, and practical design notes not found in the manufacturer datasheet.
Alternatives de remplacement direct pour MC68HC908GR8CDW — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec MC68HC908GR8CDW (même facteur de forme et même empreinte) — différant par Program Memory Size.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MC68HC908GR4CDW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MC68HC908GR8CFAE
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MC68HC908QY1CDW
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MCHC908GR8CFAE
✅ Remplacement direct✓ En stock
$2.49 / unité
Voir la fiche technique →MC68HC908GR8CDW Valeurs maximales et caractéristiques électriques
| Core | HC08 CPU08 (8-bit CISC) |
| Largeur du bus de données | 8 bit |
| Program Memory Size | 7.5 KB (7.5K x 8) Flash |
| Fréquence d'horloge maximale | 8 MHz |
| Tension d'alimentation de fonctionnement | 3.3 V / 5 V |
| Boîtier | 28-SOIC (0.295 inch, 7.50mm width) |
| Type de montage | Surface Mount |
| Peripherals | LVD, POR (per DigiKey listing) |
| Programmer Interface | Background Debug Mode (BDM) |
| Family | M68HC08 |
| Manufacturer | NXP (formerly Motorola/Freescale) |
Configuration des broches de MC68HC908GR8CDW
| Broche 1 | IRQ — External interrupt request (shared with BDM) |
| Broche 2 | RST — Reset (active low) |
| Broche 3 | VSS — Ground |
| Broche 4 | OSC1 — Crystal/oscillator input |
| Broche 5 | OSC2 — Crystal/oscillator output |
| Broche 6 | VDD — Power supply (3.3V/5V) |
| Broche 7 | PTA0 — Port A I/O bit 0 |
| Broche 8 | PTA1 — Port A I/O bit 1 |
| Broche 9 | PTA2 — Port A I/O bit 2 |
| Broche 10 | PTA3 — Port A I/O bit 3 |
| Broche 11 | PTA4 — Port A I/O bit 4 |
| Broche 12 | PTA5 — Port A I/O bit 5 |
| Broche 13 | PTA6 — Port A I/O bit 6 |
| Broche 14 | PTA7 — Port A I/O bit 7 |
| Broche 15 | PTB0 — Port B I/O bit 0 |
| Broche 16 | PTB1 — Port B I/O bit 1 |
| Broche 17 | PTB2 — Port B I/O bit 2 |
| Broche 18 | PTB3 — Port B I/O bit 3 |
| Broche 19 | PTB4 — Port B I/O bit 4 |
| Broche 20 | PTB5 — Port B I/O bit 5 |
| Broche 21 | PTB6 — Port B I/O bit 6 |
| Broche 22 | PTB7 — Port B I/O bit 7 |
| Broche 23 | PTC0 — Port C I/O bit 0 |
| Broche 24 | PTC1 — Port C I/O bit 1 |
| Broche 25 | PTC2 — Port C I/O bit 2 |
| Broche 26 | PTC3 — Port C I/O bit 3 |
| Broche 27 | PTC4 — Port C I/O bit 4 |
| Broche 28 | PTC5 — Port C I/O bit 5 |
Applications typiques
MC68HC908GR8CDW convient pour 6 applications: Remote Keyless Entry (RKE) Transmitter, Security and Alarm Panel Controller, Small Appliance and White-Good Control, Industrial Sensor Signal Conditioning, Battery-Powered Measuring Instrument, Simple Motor and Solenoid Driver Controller.
Remote Keyless Entry (RKE) Transmitter
The MC68HC908GR8CDW fits RKE transmitter designs because its 7.5KB Flash comfortably stores rolling-code firmware algorithms such as Keeloq, the 8MHz internal bus keeps current low during idle periods, and the wide 3.3-5V supply range lets it run directly from coin-cell or AA-derived rails. The 28-SOIC package is hand-solderable for low-volume fob production. Placed as the central controller between the RF transmitter, key matrix, and battery, it can wake on keypress and return to a sub-1uA stop mode, enabling multi-year battery life.
Recommandé
Security and Alarm Panel Controller
For security panels the MC68HC908GR8CDW delivers 7.5KB Flash for sensor-state machines and event logging, plus integrated LVD/POR brownout protection required for UL-listed safety equipment. The HC08 core's deterministic interrupt latency lets the MCU respond to PIR or door-loop triggers within microseconds. Using the on-chip timers for supervised loop scans and the SCI/SPI for keypad/lcd communication, the part supports 8-32 zone residential panels. Estimated: at 5V supply and 8MHz bus, the part consumes roughly 10-15mA active and drops to sub-1mA in wait mode.
Recommandé
Small Appliance and White-Good Control
Washing machines, dishwashers, and microwave ovens often run on 8-bit controllers; the MC68HC908GR8CDW's 7.5KB Flash fits standard state machine and PID control firmware, while the 28-SOIC package survives the high-temperature reflow profiles typical of appliance manufacturing. With the 3.3-5V supply tolerance, designers can power it from a transformer + rectifier + cap rail directly. The CPU08's BCD math instructions accelerate decimal arithmetic for user-facing timer displays and decode rotary-encoder inputs via the on-chip timers.
Recommandé
Industrial Sensor Signal Conditioning
Industrial sensor front-ends benefit from the MC68HC908GR8CDW's LVD threshold precision and the HC08 core's deterministic response for alarm signalling. The 28-SOIC wide-body package and industrial -40C to +85C temperature range make it suitable for factory-floor modules. Configured as the supervisory MCU around a 4-20mA loop or a Modbus-RTU slave, the part scales, linearises and transmits sensor data over the on-chip SCI. Compared with newer ARM Cortex-M0 alternatives, the GR8 is significantly cheaper in volume and easier to qualify for long-term availability.
Recommandé
Battery-Powered Measuring Instrument
The MC68HC908GR8CDW is well-matched to handheld battery-powered meters because its stop-mode current is in the sub-microamp range and its 8MHz internal oscillator eliminates the need for an external crystal in many designs. The 7.5KB Flash holds calibration tables and user-interface routines for a multimeter or clamp meter, and the LVD resets the part cleanly when the battery drops below threshold, protecting the user's measurements. Estimated: at 3.3V supply and 1MHz internal clock, the part typically draws under 1mA active and below 1uA in stop.
Recommandé
Simple Motor and Solenoid Driver Controller
For small brushed-DC motor, stepper, or solenoid control the MC68HC908GR8CDW provides enough timers to generate PWM and time-stretched drive signals without needing extra logic. Its 28-SOIC package handles the moderate switching currents associated with low-side drivers. With 7.5KB Flash you can store PID loops, soft-start ramps, and current-limit thresholds. Pair it with a Maxim/Analog Devices half-H driver to drive 1-3A loads without thermal issues at the controller side.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MC68HC908GR8CDW — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MC68HC908GR4CDW | MC68HC908QY1CDW | MCHC908GR8CFAE |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 28-SOIC (0.295 inch) | 28-SOIC - same | 28-SOIC - same | 28-SOIC / 32-LQFP variants |
| Core | HC08 CPU08 (8-bit CISC) | HC08 CPU08 (8-bit CISC) | HC08 CPU08 (8-bit CISC) | HC08 CPU08 (8-bit CISC) |
| Program Flash Memory | 7.5 KB | 4 KB (-47%) | 1.5 KB (-80%) | 7.5 KB (same) |
| Maximum Clock Frequency | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| Operating Supply Voltage | 3.3V / 5V | 3.3V / 5V | 3.3V / 5V | 3.3V / 5V |
| Peripherals | LVD, POR | LVD, POR | LVD, POR | LVD, POR |
Principaux différenciateurs
- Program flash memory density (vs MC68HC908GR4CDW)
- Family performance headroom (vs MC68HC908QY1CDW)
- Legacy supply availability (vs MCHC908GR8CFAE)
Notes de conception
Configure the LVD threshold and POR delay bits during production programming to ensure reliable reset across the operating-voltage range. The MC68HC908GR8CDW supports 3.3V and 5V supplies; selecting an LVD level below the minimum expected supply prevents false resets during regulator inrush and battery droop events. Place a 100nF ceramic decoupling capacitor within 2mm of the VDD pin (pin 6) and a bulk 4.7uF tantalum on the supply rail to handle the load-transient ringing characteristic of HC08 I/O switching.
For the 28-SOIC wide-body package (0.295 inch / 7.50mm width), follow JEDEC SOIC-W footprint guidelines: 0.062 inch land pad length, 0.025 inch lead width, and reflow profile conforming to IPC J-STD-020 moisture sensitivity level. Estimated: the 28-SOIC package draws roughly 1-1.5W/mm thermal resistance; at typical MCU operating currents (10-20 mA) and 5V supply, the part can run without heatsinking. Hand-prototyping is straightforward because the 0.05 inch lead pitch matches standard SOIC sockets.
The BDM (Background Debug Mode) interface shares the IRQ and RST pins on the MC68HC908GR8 family, so a programming adapter or breakout board is required for in-circuit programming in production. Always follow the Erase-Program-Verify Flash sequence specified in the NXP datasheet to avoid disturb on neighbouring Flash bytes, which can otherwise silently corrupt read-protected firmware. Mistake: forgetting to enable the LVD in the configuration register leads to no brownout reset and undefined behaviour during slow battery fall-off.
Informations de conformité
Compliance status not explicitly stated in the Verified Web Data. The MC68HC908GR8CDW is an automotive-grade not required part (industrial/consumer target). For AEC-Q100 qualified alternatives, consult NXP's M68HC08GR8-Q1 family.
