MC68HC908JK1ECDW - 8-Bit 8MHz MCU, 1.5KB FLASH, 20-SOIC | NXP
MPN: MC68HC908JK1ECDW ✗ Cuối đờiMC68HC908JK1ECDW Tóm tắt
What is an HC08 microcontroller? The HC08 is a family of 8-bit microcontrollers introduced in the early 1990s by Motorola (later Freescale, now NXP Semiconductors) using the M68HC08 central processor unit core. An HC08 MCU integrates CPU, FLASH/ROM program memory, RAM, timers, an A/D converter, and flexible I/O onto a single chip using a customer-specified integrated circuit (CSIC) design strategy, placing HC08 in the broader hierarchy of 8-bit MCU -> microcontroller -> embedded controller -> semiconductor IC. The MC68HC908JK1ECDW belongs to the low-cost JK1 sub-family targeting cost-sensitive applications.
Key features include 15 general-purpose I/O pins, an on-chip 12-channel 8-bit ADC, two 16-bit dual-function timer channels, a serial communications interface (SCI), and an internal oscillator with trimming capability. The device supports in-system programming and in-application programming via the ROM-resident monitor, simplifying field firmware updates without an external programmer.
The architecture centers on the enhanced M68HC08 CPU with a 16-bit stack pointer and 16-bit index register, enabling compact C-language code and efficient stack usage. The internal bus runs at one-half the oscillator frequency, and the FLASH controller supports security features including a programmable block-protect register to prevent unauthorized read-back of firmware.
Typical applications include appliance control modules, simple sensor interface boards, low-end motor-control BLDC drivers, HVAC thermostat controllers, automotive body electronics, and consumer white goods. The wide operating temperature and low cost make JK1 a popular choice for high-volume, cost-optimized designs.
A core design consideration is the trade-off between internal oscillator accuracy and external crystal cost: the trimmed internal oscillator is suitable for UART baud timing tolerance of approximately +/-2%, but precision timing applications should add an external 32.768kHz crystal or ceramic resonator to the OSC1/OSC2 pins.
This page synthesizes distributor stock data, drop-in compatible same-family alternatives, and practical design notes not aggregated on a single distributor page.
Bộ thay thế dễ dàng lắp đặt cho MC68HC908JK1ECDW — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với MC68HC908JK1ECDW (cùng hình factor và footprint) — khác nhau ở Core Architecture.
MC68HC908JK1EMDW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68HC908JK1EVDW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68HC908JK3ECDW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68HC908JK1CDW
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68HC705J1ACDW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68HC908JK1ECDW Tỷ lệ tối đa & tính chất điện
| Core Architecture | M68HC08 (HC08) |
| Bề rộng đường dữ liệu | 8-bit |
| Maximum CPU Clock Frequency | 8 MHz |
| Program Memory Size | 1.5 KB (1.5K x 8) FLASH |
| RAM Size | 128 x 8 (128 bytes) |
| Number of I/O Pins | 15 |
| Hộp / Vỏ | 20-SOIC (DW), wide body 7.50 mm |
| Kiểu lắp đặt | Surface Mount |
| ADC Resolution | 8-bit, 12 channels (per family datasheet) |
| Timer Channels | 2 x 16-bit dual-function timer channels |
| Communication Interface | SCI (Serial Communications Interface) |
| Khoảng nhiệt độ hoạt động | -40C to +85C (extended) |
| In-Circuit Programming | Monitor mode (ROM-resident) |
| Oscillator | Internal trimmed + external crystal/ceramic resonator option |
Cấu hình chân MC68HC908JK1ECDW
| Chân 1 | RST — External reset input (active low) |
| Chân 2 | IRQ — External interrupt request |
| Chân 3 | PTA0 — Port A bit 0 / ADC channel 0 |
| Chân 4 | PTA1 — Port A bit 1 / ADC channel 1 |
| Chân 5 | PTA2 — Port A bit 2 / ADC channel 2 |
| Chân 6 | PTA3 — Port A bit 3 / ADC channel 3 |
| Chân 7 | PTA4 — Port A bit 4 / ADC channel 4 |
| Chân 8 | PTA5 — Port A bit 5 / ADC channel 5 |
| Chân 9 | PTA6 — Port A bit 6 / ADC channel 6 |
| Chân 10 | PTA7 — Port A bit 7 / ADC channel 7 |
| Chân 11 | PTB0 — Port B bit 0 / ADC channel 8 |
| Chân 12 | PTB1 — Port B bit 1 / ADC channel 9 |
| Chân 13 | PTB2 — Port B bit 2 / ADC channel 10 |
| Chân 14 | PTB3 — Port B bit 3 / ADC channel 11 |
| Chân 15 | VSS — Ground |
| Chân 16 | OSC1 — Oscillator input / external crystal |
| Chân 17 | OSC2 — Oscillator output / external crystal |
| Chân 18 | VDD — Positive supply |
| Chân 19 | PTB4 — Port B bit 4 |
| Chân 20 | PTB5 — Port B bit 5 |
Ứng dụng tiêu biểu
MC68HC908JK1ECDW phù hợp cho 7 Áp dụngs: Appliance Control Modules, HVAC Thermostat Controllers, Automotive Body Electronics, Low-Cost Sensor Interface Boards, Consumer White Goods Controllers, Industrial Sensor Modules, Battery-Operated Low-Power Devices.
Appliance Control Modules
Why MC68HC908JK1ECDW fits this application: The MC68HC908JK1ECDW's combination of 1.5KB FLASH, 128 bytes RAM, 15 GPIO, and an on-chip 8-bit ADC delivers just-enough compute headroom to drive washing-machine or dishwasher user-interface PCBs at sub-$2 BOM cost. With 8MHz CPU clock the JK1 handles keypad scan, LED multiplex, and triac-based load control loops comfortably. How it is used + performance consideration: The MCU is mounted on the appliance main control board, reading the rotary encoder on PTA, driving the seven-segment display through port multiplexing, and switching a triac via PWM on PTB. Unlike an ARM Cortex-M0, the JK1 carries only one timer pair, so designers must share it between the triac zero-crossing scheduler and the buzzer tone generator, which limits sophisticated load-management algorithms.
Được đề xuất
HVAC Thermostat Controllers
Why MC68HC908JK1ECDW fits this application: The 12-channel 8-bit on-chip ADC allows direct connection of multiple thermistor and humidity sensors, and the extended -40C to +85C operating range of the E-suffix supports outdoor-mounted thermostats and furnace control boards. The HC08 core is well-suited to PID-style temperature loops running at slow update rates. How it is used + performance consideration: The MCU scans the wall-mounted thermistor bridge every 250 ms, computes a proportional-integral control law, and drives a relay through PTB. Compared with a 32-bit Cortex-M0+ thermostat MCU, the JK1 lacks the RAM for advanced scheduling and touch-button sensing; designers must add the touch IC externally if capacitive buttons are required.
Được đề xuất
Automotive Body Electronics
Why MC68HC908JK1ECDW fits this application: The 15 GPIO of the JK1 cover seat-controller, mirror-controller, and interior-light-controller pin counts at minimal cost, and the 8MHz CPU frequency handles CAN-emulated peer-to-peer or LIN-bus message-frame timing on the SCI peripheral. The extended-industrial temperature rating is acceptable for cabin electronics though not engine-compartment modules. How it is used + performance consideration: The MCU is placed at the head of a body-electronics LIN slave, receiving switch inputs on PTA and driving LED or motor-driver outputs on PTB. Trade-off: the JK1 has no hardware CAN controller, so high-speed CAN body networks need an external MCP2515 stand-alone CAN controller, raising BOM cost relative to a CAN-equipped successor MCU.
Được đề xuất
Low-Cost Sensor Interface Boards
Why MC68HC908JK1ECDW fits this application: A 1.5KB FLASH budget is sufficient for fixed-function analog-to-network bridge firmware (sensor linearization, calibration lookup, packet framing), and the integrated SCI handles UART passthrough at standard 9600/19200 baud rates from the internal trimmed oscillator. How it is used + performance consideration: The JK1 is placed on a small sensor-interface PCB, reads an analog sensor through the ADC, applies a first-order correction, and outputs the result on SCI to a downstream master controller. The 128-byte RAM limits the look-up-table size to roughly 32 entries, so designers must pre-compress calibration coefficients for use cases requiring high-accuracy conversion.
Được đề xuất
Consumer White Goods Controllers
Why MC68HC908JK1ECDW fits this application: The combination of low unit cost (sub-$4 at 1k pieces as of 2026-10-18), small 20-SOIC footprint, and integrated 12-channel ADC plus two 16-bit timers covers the entire MCU bill-of-materials for toaster-oven, rice-cooker, and microwave user-interface boards. The 15 I/O satisfy keypad-scan plus seven-segment/LED drive requirements directly. How it is used + performance consideration: Designers configure one timer for triac zero-crossing detection and the other for the beep-tone generator, sharing the same 8MHz bus. Trade-off: the small 1.5KB FLASH means complex menu UIs must use a separate display controller IC; the JK1 cannot host both user-interface graphics and the underlying control law in one device.
Được đề xuất
Industrial Sensor Modules
Why MC68HC908JK1ECDW fits this application: The -40C to +85C extended-industrial operating range and the integrated 8-bit ADC deliver factory-floor compatibility for low-cost current-loop or 0-10V analog transducer interfaces. The SCI peripheral supports 4-20 mA loop emulation or RS-485 polling at baud rates up to 115200 from an external crystal. How it is used + performance consideration: The MCU is mounted on a DIN-rail transducer PCB, scaling a 4-20 mA input through the ADC and outputting a digital reading on SCI every 100 ms. The 1.5KB FLASH budget fits a basic scaling and linearization routine but cannot host TLS or cryptographic protocol stacks; secure remote-management features require an upgraded successor MCU.
Được đề xuất
Battery-Operated Low-Power Devices
Why MC68HC908JK1ECDW fits this application: The HC08 family features STOP and WAIT low-power modes that drop current consumption to single-digit microamps, allowing the JK1 to serve battery-powered metering or remote-sensing nodes. The internal trimmed oscillator avoids the standby current of an external crystal. How it is used + performance consideration: The MCU enters STOP mode and wakes on an IRQ-triggered switch-closure event, then samples the ADC, transmits over SCI, and re-enters STOP. Trade-off: the JK1's analog peripheral leakage in STOP is higher than that of modern low-power MCUs, so average system current for battery-life calculations should use the JK1 datasheet's STOP-mode plot, not generic HC08 family guidance.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC68HC908JK1ECDW — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | MC68HC908JK1EMDW | MC68HC908JK1EVDW | MC68HC908JK3ECDW | MC68HC908JK1CDW | MC68HC705J1ACDW |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors (same) | NXP Semiconductors (same) | NXP Semiconductors (same) | NXP Semiconductors (same) | NXP Semiconductors (same) |
| Package | 20-SOIC (DW) | 20-SOIC (DW) | 20-SOIC (DW) | 20-SOIC (DW) | 20-SOIC (DW) | 20-SOIC (DW) |
| Core | HC08 (8-bit) | HC08 (8-bit) | HC08 (8-bit) | HC08 (8-bit) | HC08 (8-bit) | HC05 (8-bit) |
| Maximum CPU Clock | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 4 MHz |
| FLASH Memory Size | 1.5 KB | 1.5 KB | 1.5 KB | 4 KB | 1.5 KB | 1 KB OTP |
| RAM Size | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 64 bytes |
| Number of I/O | 15 | 15 | 15 | 20 (in 28-DIP option) | 15 | 14 |
| Operating Temperature | -40C to +85C (E-suffix) | -40C to +85C | -40C to +85C | -40C to +85C | 0C to +70C (C-suffix) | -40C to +85C |
Bảo phân biệt quan trọng
- Same-package, same-FLASH drop-in with identical 8MHz core (vsMC68HC908JK1EMDW)
- Larger FLASH without package change (vsMC68HC908JK3ECDW)
- Wider operating temperature envelope than the commercial C-suffix (vsMC68HC908JK1CDW)
Ghi chú thiết kế
Place a 100nF decoupling capacitor as physically close as possible to the VDD pin (pin 18) and a bulk 10uF aluminum-polymer or tantalum capacitor adjacent to the package. The HC08 core draws sharp current edges during FLASH programming cycles that, without proper bypassing, can corrupt adjacent port-latch reads. Keep analog VDD traces separate from digital switching nodes and use a star-ground topology if the ADC channels are referenced to a low-impedance sensor.
When using an external crystal, choose a load-capacitance crystal matching the C1/C2 values recommended in the M68HC08 family oscillator section, typically 22pF for a fundamental 8MHz crystal. Add guard traces around the OSC1/OSC2 pins and route them inside a grounded keep-out to prevent noise coupling into the I/O timing. If the trimmed internal oscillator provides acceptable UART baud accuracy (typically +/-2%), the BOM savings over a discrete crystal warrants omission.
Estimated: code memory margin for the 1.5KB FLASH is roughly 1200 lines of optimized C source before reaching the linker ceiling; reserve at least 200 bytes for interrupt-vector table and monitor-mode bootloader hooks. Designers frequently underestimate FLASH usage when including floating-point libraries; consider compiling with -Os and using integer-only math. Verify the BLOCK-PROTECT register is set to lock FLASH against unauthorized read-back in any production firmware.
The 15 I/O of the JK1 are organized into two ports (PTA and PTB); switching all 15 pins simultaneously can inject ground-bounce large enough to reset internal registers. Stagger high-current pin transitions by software add a few NOP delays between register writes to ensure stable operation. ADC sample accuracy depends on minimizing simultaneous high-frequency switching on PTA7-PTA0 (which double as ADC channels 0-7); route aggressive switching loads to PTB instead.
Thông tin tuân thủ
RoHS, REACH, lead-free and halogen-free status were not explicitly stated in the provided web-data snippets and must be verified against the current NXP product-compliance declaration (PCN/CoC) before volume procurement as of 2026-10-18. The E-suffix typically denotes lead-free NiPdAu finish on NXP legacy parts but this must be confirmed per shipment.
