MC68HC908KX8CDW - 8KB Flash 8MHz 8-bit HC08 MCU | NXP
N.º de pieza: MC68HC908KX8CDW ✗ Fin de vida| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $6.42 | $6,42 |
| 10 | $5.78 | $57,80 |
| 100 | $4.95 | $495,00 |
| 500 | $4.21 | $2.105,00 |
| 1.000 | $3.68 | $3.680,00 |
MC68HC908KX8CDW Descripción general
An HC08 microcontroller is a member of the Freescale/NXP M68HC08 family of 8-bit CISC microcontrollers, which evolved from the earlier M68HC05 architecture while preserving object-code compatibility for many instructions. The HC08 family occupies a place in the broader taxonomy of microcontrollers (MCU -> 8-bit MCU -> CISC MCU -> HC08), and HC08 parts are widely deployed in automotive body electronics, appliance controls, and industrial sensor interface designs where deterministic interrupt response and small memory footprints matter more than raw compute throughput.
Key features of the MC68HC908KX8CDW include 8KB of in-application-reprogrammable Flash, 192 bytes of on-chip RAM, an internal oscillator that eliminates the need for an external crystal in many designs, and a peripheral set tailored to low-pin-count applications. The 16-pin SOIC package provides a compact 0.300-inch body suitable for hand-solderable prototypes and high-volume surface-mount assembly. The integrated 4-channel 8-bit ADC reduces bill-of-materials cost for analog sensor interfaces such as thermistors or potentiometers.
From an architectural standpoint, the HC08 CPU delivers single-cycle instruction execution at the internal bus frequency and supports a compact instruction set with BCD arithmetic and multiply instructions, simplifying code density for control-oriented firmware. The integrated Flash supports in-circuit programming through a background debug mode, enabling field firmware updates without removing the device from the board. Compared with later ColdFire and S08 derivatives, the HC08 retains the smallest die area and lowest unit cost in the NXP 8-bit portfolio.
Typical applications include appliance control boards, HVAC thermostat interfaces, automotive accessory modules, security keypads, low-end remote controls, and battery chargers. The MC68HC908KX8CDW fits naturally in designs where a low-pin-count MCU must read a few analog sensors, drive a small display or relay, and communicate over a simple UART link without requiring a larger 32-bit Cortex-M device.
When designing with this part, ensure that the supply voltage stays within the rated VDD range and that the internal oscillator accuracy is acceptable for UART timing without an external crystal. For designs requiring higher analog accuracy or more ADC channels, consider migrating to an S08 derivative such as the MC9S08AC60 or a Cortex-M0 device in a compatible footprint.
This page synthesizes distributor pricing, drop-in same-package alternatives drawn from the HC908KX family, and practical design notes not found in the manufacturer datasheet alone.
Alternativas directas para MC68HC908KX8CDW — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con MC68HC908KX8CDW (mismo factor de forma y huella) — difiere en Core, Manufacturer, Package, Product Type, Program Memory Size.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MC68HC908KX2CDW
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MC908KX8CDWE
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MC908KX2CDWE
✅ Sustitución directa✓ En stock
$2.29 / unidad
Ver hoja de datos →MC908KX8CDW
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MC908KX8MDWE
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$7.4355 / unidad
Ver hoja de datos →MC68HC908KX8MDW
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
MC68HC908KX8CDW Valores máximos y características eléctricas
| Product Type | 8-bit Microcontroller (MCU) |
| Core | M68HC08 (CISC) |
| Program Memory Size | 8 KB (8K x 8) Flash |
| RAM Size | 192 bytes |
| Maximum CPU Frequency | 8 MHz internal bus |
| Number of I/O Pins | 13 |
| ADC | 4-channel, 8-bit |
| Oscillator Type | Internal |
| Encapsulado / Carcasa | 16-SOIC (0.300 inch / 7.50 mm width) |
| Tipo de montaje | Surface Mount |
| Packaging | Tube |
| Estado RoHS | Compliant per NXP product page |
| Lead-Free | Yes |
| Manufacturer | NXP USA Inc. (formerly Freescale / Motorola) |
Configuración de pines de MC68HC908KX8CDW
| Pin 1 | IRQ — External interrupt request input |
| Pin 2 | PTA0 — Port A bit 0 (general-purpose I/O, KBI) |
| Pin 3 | PTA1 — Port A bit 1 (general-purpose I/O, KBI) |
| Pin 4 | PTA2 — Port A bit 2 (general-purpose I/O, KBI) |
| Pin 5 | PTA3 — Port A bit 3 (general-purpose I/O, KBI) |
| Pin 6 | VDD — Positive supply voltage |
| Pin 7 | VSS — Ground reference |
| Pin 8 | OSC1 — Crystal oscillator input / external clock |
| Pin 9 | OSC2 — Crystal oscillator output |
| Pin 10 | RST — Reset input (active low) |
| Pin 11 | PTB0 — Port B bit 0 (general-purpose I/O, ADC) |
| Pin 12 | PTB1 — Port B bit 1 (general-purpose I/O, ADC) |
| Pin 13 | PTB2 — Port B bit 2 (general-purpose I/O, ADC) |
| Pin 14 | PTB3 — Port B bit 3 (general-purpose I/O, ADC) |
| Pin 15 | PTB4 — Port B bit 4 (general-purpose I/O) |
| Pin 16 | PTB5 — Port B bit 5 (general-purpose I/O) |
Aplicaciones típicas
MC68HC908KX8CDW es adecuado para 6 aplicacións: Appliance Control Boards, HVAC Thermostat Interface, Automotive Accessory Modules, Security Keypad and Access Control, Battery Charger Controllers, Remote Control and IR Transmitters.
Appliance Control Boards
The MC68HC908KX8CDW suits washing-machine, dishwasher, and microwave control boards where 8KB Flash holds state-machine firmware, 13 GPIOs drive relays and switches, and the 4-channel 8-bit ADC reads temperature and level sensors. Its internal oscillator eliminates an external crystal and reduces BOM cost, while the HC08 CISC core delivers deterministic interrupt response for safety-critical door-switch and over-temperature events. The 16-SOIC footprint keeps the PCB small enough to fit behind an appliance keypad.
Recomendado
HVAC Thermostat Interface
The MC68HC908KX8CDW fits wall-mount thermostat designs that read one or two temperature sensors via its 8-bit ADC, drive a small LCD or LED bar graph from GPIO pins, and switch a low-current relay through a transistor. Its 192-byte RAM is sufficient for a smoothed-temperature filter and a hysteresis state machine, and the 8KB Flash holds menu and scheduling logic. The HC08 core's short interrupt latency ensures the keypad and set-point updates stay responsive during user interaction.
Recomendado
Automotive Accessory Modules
Automotive accessory modules such as seat-belt reminder chimes, mirror-adjust controllers, and ambient lighting drivers use the MC68HC908KX8CDW because it packs 8KB Flash, an 8-bit ADC, and 13 GPIOs into a 16-SOIC that survives under-dash temperatures when ordered with the industrial 'M' grade suffix. The HC08 core's deterministic interrupt handling meets the timing requirements of LIN-sleep wake-up sequences in body-electronics networks. Engineers pair the MCU with a small LIN transceiver and a power-management IC to build a complete sub-assembly.
Recomendado
Security Keypad and Access Control
Security keypads and access-control pads use the MC68HC908KX8CDW to scan a 3x4 or 4x4 matrix keypad through the GPIO pins and drive a piezo buzzer or LED ring for feedback. The 4-channel 8-bit ADC reads a tamper-detection switch or backup-battery voltage, while the 8KB Flash holds the PIN-verification state machine and EEPROM emulation for stored credentials. The HC08 core's low interrupt latency keeps keypad debounce timing predictable across temperature variations.
Recomendado
Battery Charger Controllers
Low-end battery chargers for power tools, e-bikes, and emergency lighting use the MC68HC908KX8CDW to measure cell voltage and current through the 8-bit ADC, drive MOSFET gate drivers from GPIO pins, and run CC/CV charge algorithms in 8KB Flash. The 192-byte RAM is sufficient to hold the latest ADC samples and a moving-average filter, and the internal oscillator keeps the BOM to a single IC plus passives. The HC08 core's deterministic timing simplifies implementing the safety timer required by lithium-cell charging profiles.
Recomendado
Remote Control and IR Transmitters
Universal remote controls, ceiling-fan remotes, and toy transmitters fit well with the MC68HC908KX8CDW, because the device's 13 GPIOs scan a key matrix and modulate an IR LED, while 8KB Flash holds the protocol database for popular TV and AV brands. The HC08 core's low-power wait mode extends battery life between button presses, and the internal oscillator removes the need for an external resonator. The 16-SOIC package fits inside a slim AA-battery form factor.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MC68HC908KX8CDW — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MC68HC908KX2CDW | MC908KX8CDWE | MC908KX2CDWE | MC908KX8CDW | MC908KX8MDWE |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-SOIC (0.300 inch) | 16-SOIC (0.300 inch) - same | 16-SOIC (0.300 inch) - same | 16-SOIC (0.300 inch) - same | 16-SOIC (0.300 inch) - same | 16-SOIC (0.300 inch) - same |
| Flash Memory | 8 KB | 2 KB (-75%) | 8 KB (same) | 2 KB (-75%) | 8 KB (same) | 8 KB (same) |
| RAM | 192 bytes | 192 bytes (same) | 192 bytes (same) | 192 bytes (same) | 192 bytes (same) | 192 bytes (same) |
| CPU Frequency | 8 MHz | 8 MHz (same) | 8 MHz (same) | 8 MHz (same) | 8 MHz (same) | 8 MHz (same) |
| Core Architecture | HC08 (CISC) | HC08 (CISC) - same | HC08 (CISC) - same | HC08 (CISC) - same | HC08 (CISC) - same | HC08 (CISC) - same |
| GPIO Pins | 13 | 13 (same) | 13 (same) | 13 (same) | 13 (same) | 13 (same) |
| ADC | 4-ch, 8-bit | 4-ch, 8-bit (same) | 4-ch, 8-bit (same) | 4-ch, 8-bit (same) | 4-ch, 8-bit (same) | 4-ch, 8-bit (same) |
| Temperature Grade (suffix) | Commercial 'C' (0 to +70 C) | Commercial 'C' | Commercial 'C' | Commercial 'C' | Commercial 'C' | Industrial 'M' (-40 to +85 C) |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND |
Diferenciadores clave
- 8 KB Flash in 16-SOIC footprint (frente a MC68HC908KX2CDW)
- Updated NXP part-number prefix (frente a MC908KX8CDWE)
- Industrial temperature grade option (frente a MC908KX8MDWE)
- HC08 CISC core with deterministic interrupts (frente a Generic Cortex-M0 MCU)
Notas de diseño
Do not assume the internal oscillator accuracy is tight for UART baud rates above 9600 baud; for 115200 baud or LIN-bus timing, add an external crystal on OSC1/OSC2 or migrate to an S08 derivative with a trimmed internal oscillator. The HC908KX internal oscillator is trimmed at the factory but can drift up to several percent over the full temperature range, which is acceptable for low-speed GPIO control but problematic for serial communications.
Decouple VDD (pin 6) with a 100 nF ceramic capacitor placed within 5 mm of the supply pin and a bulk 10 uF electrolytic or tantalum capacitor at the board power entry. The HC08 core draws sharp transient currents during Flash programming and ADC conversions, and insufficient decoupling can cause code runaway or ADC inaccuracy.
Keep the analog input traces (PTB0-PTB3) short and routed away from switching nodes such as relay coils or PWM outputs to minimize ADC coupling noise. Place a small RC filter (100 ohm + 100 nF) on each analog input when the source impedance exceeds 5 kohm to avoid ADC sample-and-hold errors. Use a guard ring around analog traces tied to VSS to reduce digital crosstalk.
Route the RST line to a dedicated header for in-circuit programming and route it through a 10 kohm pull-up to VDD and a 100 nF capacitor to VSS to ensure a clean power-on reset. If the design uses an external supervisor, connect the supervisor output to RST directly without any series resistance to guarantee a valid reset pulse during brownout events.
The MC68HC908KX8CDW is marked NRND, so do not specify it for new designs without confirming long-term supply with NXP. For new designs, evaluate the MC9S08AC60 (S08 family, active lifecycle) or a Cortex-M0 MCU such as the Kinetis E0 in a compatible 16-SOIC footprint, then plan a one-time firmware rewrite from HC08 assembly to C or to S08/Cortex-M assembly.
Información de cumplimiento
RoHS compliance per NXP product page. Not AEC-Q100 qualified; the part targets commercial and industrial environments rather than automotive safety-critical applications. Reach and conflict-minerals statements per NXP corporate policy.
