MC908MR8CDWE - HC08 8-Bit MCU 8KB Flash 8MHz | NXP | 28-SOIC
N.º da peça: MC908MR8CDWE ✗ Fim de vida| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $6.91 | $6,91 |
| 10 | $6.22 | $62,20 |
| 100 | $5.53 | $553,00 |
| 500 | $4.84 | $2.420,00 |
| 1.000 | $4.14 | $4.140,00 |
MC908MR8CDWE Visão geral
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, memory, and peripherals. The HC08 is Freescale/NXP's classic 8-bit CISC architecture, sitting in the hierarchy: MCU -> 8-bit microcontroller -> embedded controller -> semiconductor. The 'MR' sub-family specifically targets motor-control and power-conversion applications by combining an ADC with PWM-friendly timer architecture, making it a popular choice for low-cost BLDC and brushed-DC control loops.
Key features include 8KB (8K x 8) FLASH for firmware storage, an internal oscillator that eliminates external crystals in cost-sensitive designs, an on-chip ADC for analog feedback, low-voltage detect, and an asynchronous SCI/UART for serial communications. The 28-SOIC package with 7.50 mm body width is the most popular industrial SOIC footprint, easing hand-soldering and wave-solder assembly.
The HC08 core uses a CISC instruction set with multiple addressing modes and runs one instruction per bus cycle, giving deterministic throughput for real-time control loops. FLASH memory allows in-circuit reprogramming, while the integrated brown-out and low-voltage-detect blocks protect against code corruption on power-down.
Typical applications include small BLDC and brushed-DC motor controllers, white-goods and appliance control boards, industrial sensor interfaces, low-cost HVAC damper actuators, and battery-powered handheld instruments where a compact 8-bit MCU is sufficient.
When designing with this part, verify the 12 GPIO budget against your board's pin count, add 0.1 uF decoupling on VDD/AVDD/VSS pairs, and confirm the 5V/3.3V supply rail matches your interface logic. Programming is via the standard HC08 MON08 or serial bootloader interface.
This page consolidates distributor pricing, drop-in alternatives, and engineering guidance not present on a single manufacturer product page, supporting faster sourcing and design-in decisions.
Alternativas drop-in para MC908MR8CDWE — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MC908MR16CDWE
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC908MR32CDWE
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC908MR8MDWE
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC908MR8CPE
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC908MR8VDWE
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC908MR8CDWE Classificações máximas e características elétricas
| Core Architecture | M68HC08 (8-bit CISC) |
| Program Memory | 8 KB (8K x 8) FLASH |
| RAM Size | 256 x 8 bytes |
| Maximum Bus Frequency | 8.2 MHz internal |
| Tensão de alimentação | 3.3 V / 5 V dual |
| GPIO Count | 12 |
| ADC | On-chip analog-to-digital converter |
| Oscillator | Internal |
| Encapsulamento | 28-SOIC (0.295 in / 7.50 mm width) |
| Tipo de montagem | Surface Mount |
Configuração de pinos do MC908MR8CDWE
| Pino 1 | IRQ — External interrupt request input |
| Pino 2 | PTA0 — General-purpose I/O / ADC channel |
| Pino 3 | PTA1 — General-purpose I/O / ADC channel |
| Pino 4 | PTA2 — General-purpose I/O / ADC channel |
| Pino 5 | PTA3 — General-purpose I/O / ADC channel |
| Pino 6 | PTA4 — General-purpose I/O / ADC channel |
| Pino 7 | PTA5 — General-purpose I/O / ADC channel |
| Pino 8 | PTA6 — General-purpose I/O / ADC channel |
| Pino 9 | PTA7 — General-purpose I/O / ADC channel |
| Pino 10 | VSS — Ground reference |
| Pino 11 | VDD — Positive supply voltage (3.3 V / 5 V) |
| Pino 12 | OSC1 — Oscillator input / external clock |
| Pino 13 | OSC2 — Oscillator output |
| Pino 14 | PTB0 — General-purpose I/O / timer channel |
| Pino 15 | PTB1 — General-purpose I/O / timer channel |
| Pino 16 | PTB2 — General-purpose I/O / timer channel |
| Pino 17 | PTB3 — General-purpose I/O / timer channel |
| Pino 18 | PTB4 — General-purpose I/O / timer channel |
| Pino 19 | PTB5 — General-purpose I/O / timer channel |
| Pino 20 | PTB6 — General-purpose I/O / timer channel |
| Pino 21 | PTB7 — General-purpose I/O / timer channel |
| Pino 22 | PTC0 — General-purpose I/O [DATA_NEEDED: peripheral function] |
| Pino 23 | PTC1 — General-purpose I/O [DATA_NEEDED: peripheral function] |
| Pino 24 | RST — Active-low reset input |
| Pino 25 | TXD — SCI/UART transmit output |
| Pino 26 | RXD — SCI/UART receive input |
| Pino 27 | AVDD — Analog supply voltage |
| Pino 28 | AVSS — Analog ground reference |
Aplicações típicas
MC908MR8CDWE é adequado para 6 aplicaçãos: Brushed DC Motor Control, White Goods Appliance Control, Industrial Sensor Interface Module, Battery-Powered Handheld Instruments, HVAC Damper and Valve Actuator, Low-Cost BLDC Fan Controller.
Brushed DC Motor Control
The MC908MR8CDWE's on-chip ADC and PWM-capable timers make it a strong fit for brushed DC motor control in cost-sensitive appliances. With 8 KB of FLASH it can hold a complete PI speed-control loop plus commutation logic, while the 8 MHz HC08 core provides deterministic instruction timing critical for maintaining stable RPM under varying load. The 12 GPIO count is sufficient for one H-bridge direction pin pair, current-sense input, and a fault output. Operating from 3.3 V or 5 V, it interfaces directly to low-side gate drivers without level shifters.
Recomendado
White Goods Appliance Control
Washing machines, dishwashers, and small kitchen appliances benefit from the MC908MR8CDWE's FLASH reprogrammability, allowing firmware updates via the UART bootloader without removing the MCU from the board. The industrial temperature rating, internal oscillator (no crystal required), and 28-SOIC package keep BOM cost low for high-volume consumer products. With 12 GPIO the MCU can drive relay coils, read door switches, scan a keypad matrix, and drive a 7-segment display through a simple transistor array.
Recomendado
Industrial Sensor Interface Module
The MC908MR8CDWE's integrated ADC and UART fit industrial sensor interface modules that must digitize analog signals and forward them to a host controller. The internal oscillator eliminates crystal cost, while the 8 KB FLASH stores calibration tables and linearization curves. The 5 V tolerance on digital I/O enables direct connection to legacy industrial bus transceivers. Designers appreciate the deterministic HC08 execution for real-time sampling loops, and the SOIC package simplifies conformal-coated board assembly.
Recomendado
Battery-Powered Handheld Instruments
Low-cost handheld multimeters, IR thermometers, and HVAC service tools use the MC908MR8CDWE because the HC08 core's low active current and the integrated brown-out detector extend battery life while protecting the FLASH from low-voltage corruption. The 12 GPIO budget covers LCD segment drivers, button scan, and a UART to an isolated Bluetooth or USB-to-serial bridge. The internal oscillator removes the bulky crystal, reducing board area and improving drop-test reliability.
Recomendado
HVAC Damper and Valve Actuator
Building automation damper and valve actuators run on the MC908MR8CDWE because the MCU's 8 KB FLASH holds the proportional control algorithm, while the on-chip ADC reads position feedback from a potentiometer or Hall sensor. The internal oscillator keeps the BOM to MCU, H-bridge driver, and a handful of passives, suiting the aggressive price targets of commercial HVAC zoning products. Operating from 24 VAC-derived 5 V supplies, the part tolerates the brown-out events common in transformer-fed actuator circuits.
Recomendado
Low-Cost BLDC Fan Controller
Small cooling fans and PC case fans use the MC908MR8CDWE as a single-chip BLDC controller, taking Hall-sensor inputs through the GPIO, generating complementary PWM through timers, and reading back EMF through the ADC for sensorless or sensor-fused commutation. The 8 MHz bus rate is sufficient for low-RPM fans where switching losses dominate, and the FLASH lets manufacturers customize startup curves per fan model. The 28-SOIC footprint is easy to place on small circular fan PCBs.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MC908MR8CDWE — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MC908MR16CDWE | MC908MR32CDWE | MC908MR8MDWE | MC908MR8CPE | MC908MR8VDWE |
|---|---|---|---|---|---|---|
| Package | 28-SOIC (0.295 in) | 28-SOIC (0.295 in) - same | 28-SOIC (0.295 in) - same | 28-SOIC (0.295 in) - same | 28-SOIC (0.295 in) - same | 28-SOIC (0.295 in) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| FLASH Size | 8 KB | 16 KB | 32 KB | 8 KB | 8 KB | 8 KB |
| Bus Frequency | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| GPIO Count | 12 | 12 | 12 | 12 | 12 | 12 |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND |
Principais diferenciais
- On-chip ADC with motor-control timers (vs MC908JL3ECDWE)
- Internal oscillator eliminates external crystal (vs Generic HC05 with external crystal)
- 28-SOIC footprint shared with HC08MR family (vs 28-DIP HC908MR parts)
- 5 V tolerant I/O for industrial interfaces (vs 3.3 V-only modern ARM Cortex-M0 MCUs)
Notas de projeto
Decouple VDD/AVDD with 0.1 uF ceramic capacitors placed within 5 mm of each supply pin, plus a bulk 10 uF tantalum or aluminum-polymer capacitor at the board entry. The HC08MR's ADC shares analog and digital supplies; route AVSS as a star ground back to the regulator to avoid digital return-current noise coupling into ADC readings. The brown-out detector must be enabled in firmware to protect FLASH integrity on power-down.
Keep the 28-SOIC footprint on a 1.27 mm pitch SOIC land pattern with 0.5 mm clearance to neighboring traces. Provide a ground pour under the package to reduce thermal rise; the HC08 draws tens of mA active. Route the RESET line away from PWM outputs to avoid false resets during heavy switching transients, and place a 10 kohm pull-up on RST with a 1 nF capacitor to ground for noise immunity.
Do not assume the HC08MR and HC08JL families are interchangeable: their memory maps, peripheral addresses, and interrupt vectors differ. When migrating firmware between them, regenerate the linker script and vector table. Also verify that your compiler/linker output matches the 8 KB FLASH boundary; out-of-b FLASH writes will silently corrupt adjacent memory. Use the NXP-supplied header files rather than rolling your own register definitions.
Place the optional external crystal (if used instead of the internal oscillator) within 5 mm of OSC1/OSC2 with a grounded guard ring. Keep oscillator traces short and symmetric to minimize duty-cycle distortion. If the application uses the ADC, isolate the analog inputs (PTA0-PTA7) on one board edge away from PWM-switching traces, and use a 100 nF capacitor at each analog input pin for anti-aliasing.
Informações de conformidade
Lifecycle status is NRND (Not Recommended for New Designs) per NXP. RoHS, REACH, lead-free, and halogen-free status not confirmed in the verified web data and marked as [DATA_NEEDED]. Not AEC-Q100 qualified - this is a general-purpose industrial MCU.
