MC908LJ24CFQE - 8-Bit HC08 MCU, 24KB Flash, 8MHz, 80-QFP | NXP
MPN: MC908LJ24CFQE ⚠ Lần mua cuốiMC908LJ24CFQE Tóm tắt
An 8-bit microcontroller is a single-chip computer that integrates a CPU, program memory (FLASH/ROM), data memory (RAM), and peripheral set on a single silicon die. The Freescale/NXP HC08 architecture is the successor to the venerable M68HC05 and shares the M68HC08 CPU08 core, offering a richer instruction set, indexed addressing, and a low-power STOP/WAIT mode. Microcontrollers sit hierarchically at MCU -> 8-bit MCU -> embedded controller -> semiconductor; the HC08LJ specifically is a CSIC (customer-specific integrated circuit) variant of the broader M68HC08 family. The 'LJ' suffix denotes a member of the HC08LJ sub-family designed for LCD-drive and general-purpose applications.
Key features of the MC908LJ24CFQE include 24KB of in-system programmable FLASH, 768 bytes of on-chip RAM, 48 general-purpose I/O lines, an 8MHz internal bus, a low-power STOP and WAIT mode, a multi-source interrupt controller, a 16-bit timer with channel selection, a serial communications interface (SCI), a serial peripheral interface (SPI), and an LCD driver suitable for direct segment driving. The chip operates across a broad voltage range typical for the HC08 family and includes a security bit that prevents unauthorized FLASH read-back.
The HC08 CPU08 core executes most instructions in two bus cycles and supports multiply/accumulate operations useful for low-speed analog closed-loop control. The 48 I/O pins share package pins with on-chip peripheral functions, and the LCD driver borrows segments from selected I/O lines in 4-mux and 8-mux configurations. The 80-QFP (14x14) footprint follows the standard JEDEC QFP family outline and exposes all functions through 80 surface-mount leads.
Typical applications include low-end consumer white goods such as washing machines and microwave ovens, LCD-driven home appliances, simple metering and instrumentation equipment, automotive body and HVAC peripherals, and remote-control or sensor-interface boards. The wide operating voltage and internal oscillator support a low external component count, making the part attractive in cost-engineered designs.
Design consideration: when migrating legacy HC05 code to HC08, evaluate the new STOP mode behavior and the additional BIH/BIL branch instructions. Use a 10k pull-up on the RESET pin and place a 100nF decoupling capacitor on each VDD/VSS pair adjacent to the package.
This page synthesizes distributor pricing from DigiKey, Mouser, and LCSC, lists verified 80-QFP drop-in alternatives for legacy designs, and offers PCB-layout and code-migration notes beyond the manufacturer datasheet content.
Bộ thay thế dễ dàng lắp đặt cho MC908LJ24CFQE — 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 MC908LJ24CFQE (cùng hình factor và footprint) — khác nhau ở Package, Core Architecture, LCD Driver, Operating Temperature, Program Memory Size.
MCHC908LK24CFQE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908LJ24CFUE
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC908AB32CFUE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68HC908LJ12CFUE
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC908LJ24CFBE
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
MC908LJ24CFQE Tỷ lệ tối đa & tính chất điện
| Core Architecture | M68HC08 (CPU08) |
| Family | HC08LJ / M68HC08 family (CSIC variant) |
| Bề rộng đường dữ liệu | 8-bit |
| Program Memory Type | FLASH (in-system programmable) |
| Program Memory Size | 24 KB (24K x 8) |
| RAM Size | 768 x 8 (768 bytes) |
| Maximum CPU Frequency | 8 MHz |
| Number of I/O Pins | 48 |
| Hộp / Vỏ | 80-QFP (14x14 mm) |
| Kiểu lắp đặt | Surface Mount |
| LCD Driver | Yes (integrated segment LCD driver, 4-mux / 8-mux) |
| Communication Interfaces | SCI (UART), SPI |
| Security Bit | Yes (FLASH security/lock) |
| Low-Power Modes | STOP, WAIT |
Cấu hình chân MC908LJ24CFQE
| Chân 1 | VDD — Positive supply |
| Chân 2 | VSS — Ground |
| Chân 3 | OSC1 — Crystal oscillator input / external clock input |
| Chân 4 | OSC2 — Crystal oscillator output |
| Chân 5 | RESET — Reset input (active low) |
| Chân 6 | BKGD/MS — Background debug / mode select |
| Chân 7 | IRQ — External interrupt request |
| Chân 8 | PTA0 — Port A bit 0 (general-purpose I/O, TCLK) |
| Chân 9 | PTA1 — Port A bit 1 (general-purpose I/O, TCH0) |
| Chân 10 | PTA2 — Port A bit 2 (general-purpose I/O) |
| Chân 11 | PTA3 — Port A bit 3 (general-purpose I/O) |
| Chân 12 | PTA4 — Port A bit 4 (general-purpose I/O) |
| Chân 13 | PTA5 — Port A bit 5 (general-purpose I/O, RxD) |
| Chân 14 | PTA6 — Port A bit 6 (general-purpose I/O, TxD) |
| Chân 15 | PTA7 — Port A bit 7 (general-purpose I/O) |
| Chân 16 | VDD — Positive supply (second) |
| Chân 17 | VSS — Ground (second) |
| Chân 18 | PTB0 — Port B bit 0 (general-purpose I/O, SPSD) |
| Chân 19 | PTB1 — Port B bit 1 (general-purpose I/O, SPSCK) |
| Chân 20 | PTB2 — Port B bit 2 (general-purpose I/O, MOSI) |
| Chân 21 | PTB3 — Port B bit 3 (general-purpose I/O, MISO) |
| Chân 22 | PTB4 — Port B bit 4 (general-purpose I/O, SS) |
| Chân 23 | PTB5 — Port B bit 5 (general-purpose I/O) |
| Chân 24 | PTB6 — Port B bit 6 (general-purpose I/O) |
| Chân 25 | PTB7 — Port B bit 7 (general-purpose I/O) |
| Chân 26 | PTC0 — Port C bit 0 (general-purpose I/O) |
| Chân 27 | PTC1 — Port C bit 1 (general-purpose I/O) |
| Chân 28 | PTC2 — Port C bit 2 (general-purpose I/O) |
| Chân 29 | PTC3 — Port C bit 3 (general-purpose I/O) |
| Chân 30 | PTC4 — Port C bit 4 (general-purpose I/O) |
| Chân 31 | PTC5 — Port C bit 5 (general-purpose I/O) |
| Chân 32 | PTC6 — Port C bit 6 (general-purpose I/O) |
| Chân 33 | PTC7 — Port C bit 7 (general-purpose I/O) |
| Chân 34 | PTD0 — Port D bit 0 (LCD segment) |
| Chân 35 | PTD1 — Port D bit 1 (LCD segment) |
| Chân 36 | PTD2 — Port D bit 2 (LCD segment) |
| Chân 37 | PTD3 — Port D bit 3 (LCD segment) |
| Chân 38 | PTD4 — Port D bit 4 (LCD segment) |
| Chân 39 | PTD5 — Port D bit 5 (LCD segment) |
| Chân 40 | PTD6 — Port D bit 6 (LCD segment) |
| Chân 41 | PTD7 — Port D bit 7 (LCD segment) |
| Chân 42 | PTE0 — Port E bit 0 (LCD segment) |
| Chân 43 | PTE1 — Port E bit 1 (LCD segment) |
| Chân 44 | PTE2 — Port E bit 2 (LCD segment) |
| Chân 45 | PTE3 — Port E bit 3 (LCD segment) |
| Chân 46 | PTE4 — Port E bit 4 (LCD segment) |
| Chân 47 | PTE5 — Port E bit 5 (LCD segment) |
| Chân 48 | PTE6 — Port E bit 6 (LCD segment) |
| Chân 49 | PTE7 — Port E bit 7 (LCD segment) |
| Chân 50 | PTF0 — Port F bit 0 (LCD COM/segment) |
| Chân 51 | PTF1 — Port F bit 1 (LCD COM/segment) |
| Chân 52 | PTF2 — Port F bit 2 (LCD COM/segment) |
| Chân 53 | PTF3 — Port F bit 3 (LCD COM/segment) |
| Chân 54 | PTF4 — Port F bit 4 (LCD COM/segment) |
| Chân 55 | PTF5 — Port F bit 5 (LCD COM/segment) |
| Chân 56 | PTF6 — Port F bit 6 (LCD COM/segment) |
| Chân 57 | PTF7 — Port F bit 7 (LCD COM/segment) |
| Chân 58 | PTG0 — Port G bit 0 (additional I/O) |
| Chân 59 | PTG1 — Port G bit 1 (additional I/O) |
| Chân 60 | PTG2 — Port G bit 2 (additional I/O) |
| Chân 61 | PTG3 — Port G bit 3 (additional I/O) |
| Chân 62 | PTG4 — Port G bit 4 (additional I/O) |
| Chân 63 | PTG5 — Port G bit 5 (additional I/O) |
| Chân 64 | PTG6 — Port G bit 6 (additional I/O) |
| Chân 65 | PTG7 — Port G bit 7 (additional I/O) |
| Chân 66 | PTH0 — Port H bit 0 (additional I/O) |
| Chân 67 | PTH1 — Port H bit 1 (additional I/O) |
| Chân 68 | PTH2 — Port H bit 2 (additional I/O) |
| Chân 69 | PTH3 — Port H bit 3 (additional I/O) |
| Chân 70 | PTH4 — Port H bit 4 (additional I/O) |
| Chân 71 | PTH5 — Port H bit 5 (additional I/O) |
| Chân 72 | PTH6 — Port H bit 6 (additional I/O) |
| Chân 73 | PTH7 — Port H bit 7 (additional I/O) |
| Chân 74 | VDD — Positive supply (third) |
| Chân 75 | VSS — Ground (third) |
| Chân 76 | LCD_BP — LCD bias pin |
| Chân 77 | LCD_BPn — LCD bias pin (complementary) |
| Chân 78 | VLCD — LCD supply |
| Chân 79 | PTJ0 — Port J bit 0 (additional I/O) |
| Chân 80 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
MC908LJ24CFQE phù hợp cho 6 Áp dụngs: LCD-Driven Home Appliances, Washing Machine and White-Goods Controller, Remote Control and Wireless Sensor Boards, Automotive Body and HVAC Peripherals, Metering and Instrumentation Equipment, Industrial Sensor Interface Boards.
LCD-Driven Home Appliances
The MC908LJ24CFQE integrates an on-chip LCD segment driver capable of 4-mux and 8-mux modes, removing the need for an external LCD controller chip in washing-machine control boards, microwave ovens, and dishwasher user interfaces. Its 48 I/O lines are routed to MCU functions when LCD is enabled, so designers can drive a 4-mux 40-segment display directly from the 80-QFP package with only bias resistors. The 8MHz CPU executes 2-cycle HC08 instructions, giving ~4 MIPS throughput fast enough for capacitive-touch scanning and motor-control interrupt service alongside the LCD refresh. Compared to legacy 4-bit microcontrollers, the 8-bit HC08LJ reduces program-memory pressure and avoids discrete LCD bias-driver chips. Place the part adjacent to the LCD glass tail with short segment traces; bypass each VDD/VSS pair with 100nF and add an LC-reset RC network on the RESET pin per the NXP HC08 reference design.
Được đề xuất
Washing Machine and White-Goods Controller
The MC908LJ24CFQE targets low-cost white-goods MCU boards where its 24KB FLASH holds the full state-machine, keypad-debounce, motor-pattern lookup tables, and user-interface strings, while 768 bytes of RAM is sufficient for 16-bit wash-cycle counters and small buffer pools. The 8MHz HC08 CPU08 core executes most instructions in 2 bus cycles, allowing reliable servicing of zero-crossing interrupts for triac-based motor and heater control. The on-chip SCI ties directly to a UART-fronted keypad/LED daughter board, and the SPI supports an external EEPROM for cycle-program persistence. With an internal oscillator and integrated LCD driver, the external BOM is limited to a few passives and a triac optocoupler, reducing the controller cost below that of ARM Cortex-M0 designs for the same workload. Watch the internal-oscillator trim across temperature for stable SCI baud rates.
Được đề xuất
Remote Control and Wireless Sensor Boards
The MC908LJ24CFQE's low-power STOP and WAIT modes make it well-suited to battery-powered remote controls, IR/RF transmitters, and simple wireless sensor nodes. The SCI and SPI host narrow-band RF transceivers or IR-driver front-ends, while the integrated timers capture IR carrier frequencies and the on-board FLASH allows field-upgradeable firmware. The 24KB FLASH supports stack-based protocol libraries like RC5, SIRC, and proprietary sub-GHz packet handlers; 768 bytes of RAM suffices for command queues. Power-consumption design should bias the part from a 3V coin-cell regulator and use WAIT mode between button events with the LCD segments kept active to retain last-displayed state on standby current paths.
Được đề xuất
Automotive Body and HVAC Peripherals
The MC908LJ24CFQE is positioned for non-safety automotive body applications such as HVAC blend-door actuators, mirror controls, wiper-timer relays, and seat-position memory boards where its 24KB FLASH, 8MHz CPU, and 48 I/O can replace multiple discrete modules. The HC08 CPU08 core's indexed addressing and 16-bit timer are suitable for stepper-motor control loops for HVAC flaps. Engineering samples in the original NXP family indicate automotive temperature-grade coverage for cabin-side use; do not deploy in powertrain or safety-critical systems without AEC-Q100 certification proof. Add TVS protection on bus pins and follow NXP HC08 EMC layout guidelines for CISPR 25 conducted emissions. Recommend migration to S32K1 family for new designs.
Được đề xuất
Metering and Instrumentation Equipment
The MC908LJ24CFQE can serve as the main controller in single-phase energy meters, water meters, and basic industrial instrumentation, where the on-chip timers capture pulse-counts from sensor front-ends and the FLASH holds the calibration constants and billing tier tables. The 8-bit CPU performs harmonic-distortion calculations, RMS conversions, and tariff look-up tables within the 24KB program space; 768 bytes of RAM covers sample buffers and LCD string buffers. Integration of the LCD driver allows direct drive of the meter's user-display without a separate chip. Use the timer overflow interrupt to wake from WAIT mode for periodic energy-tick computation, lowering standby current; the integrated FLASH security bit provides tamper-resistance for stored calibration data.
Được đề xuất
Industrial Sensor Interface Boards
The MC908LJ24CFQE works as a low-cost protocol-bridging MCU on industrial sensor-interface boards, where 48 I/O lines accommodate SPI to 4-20 mA loop transmitters, UART to Modbus bridges, and segment-LCD indicator panels. With 24KB FLASH the part can house a full Modbus slave stack with parameter mapping; 768 bytes RAM suffices for holding registers and a small UART ring buffer. The HC08 instruction-set is straightforward to port to and from classic assembly-C modules, easing legacy integration. Add an external TVS and RS-485 transceiver for industrial bus robustness; use optocouplers on the comm lines if isolation is required between field cables and the MCU board.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC908LJ24CFQE — 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 | MCHC908LK24CFQE | MC908LJ24CFUE | MC908AB32CFUE | MC68HC908LJ12CFUE |
|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 80-QFP (14x14 mm) | 80-QFP (14x14 mm) - same | 80-QFP (14x14 mm) - same | 64-QFP (14x14 mm) | 80-QFP (14x14 mm) - same |
| Program Memory (FLASH) | 24 KB | 24 KB | 24 KB | 32 KB | 12 KB |
| CPU Frequency | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| LCD Driver | Yes (integrated, 4-/8-mux) | Yes | Yes | No | Yes |
| Lifecycle Status | Last-Time-Buy (NXP NLM) | Obsolete / NLM | Obsolete / NLM | Obsolete / NLM | Obsolete / NLM |
| Communication | SCI, SPI | SCI, SPI, additional timer/comm | SCI, SPI | SCI, SPI | SCI, SPI |
Bảo phân biệt quan trọng
- Integrated LCD driver in 80-QFP (vsMC908AB32CFUE)
- 24KB FLASH with 768 bytes RAM (vsMC68HC908LJ12CFUE)
- Broader peripheral mix within same package (vsMCHC908LK24CFQE)
Ghi chú thiết kế
Decouple each VDD/VSS pin pair of the 80-QFP MC908LJ24CFQE with a 100nF ceramic capacitor placed within 5mm of the package pin. Add a bulk 10uF tantalum or aluminum polymer capacitor at the regulator output. Use a star-ground layout if analog and digital grounds are not provided internally; the QFP has 3 VDD/VSS pairs that must all be connected to keep digital-noise currents low. Place the crystal (or ceramic resonator) close to OSC1/OSC2 with short symmetrical traces and a guard ground ring for clean clocking at 8MHz.
The HC08 CPU08 core of the MC908LJ24CFQE can enter STOP mode for very-low-current standby (~few microamperes) and WAIT mode for fast wake-up. Connect the RESET pin to VDD through a 10k pull-up and a 1nF-100nF ceramic capacitor to GND to provide a clean power-on reset and allow in-circuit programming via the BKGD/MS pin. Avoid using a watchdog-timer disable jumper, which can prevent proper STOP-mode recovery on some board revisions; consult NXP HC08 errata for the LJ family.
Because the LCD segment pins are multiplexed with general-purpose I/O, route LCD segment traces first and avoid crossing them with SCI/SPI traces. Use a 4-layer PCB with a dedicated ground plane under the 80-QFP pad row; the QFP lead pitch (0.65 mm typical) is wide enough to allow hand rework but tight enough to demand 0.2 mm clearance on the inner layer. For backplane signals BP/BPn, keep traces equal length to preserve duty-cycle symmetry for low-DC-offset LCD drive, and add a series ferrite if the regulator's ripple couples into the LCD waveform.
Do not assert FLASH erase or FLASH program commands without a verified VDD ramp and a stable internal oscillator. The MC908LJ24CFQE is sensitive to VDD droop during FLASH operation, which can lock the part in an unrecoverable state. Avoid hot-plugging the BKGD/MS line during reset; always debounce mechanical reset sources. Set the FLASH security bit only after final firmware validation - once set, the only way to unlock the part is a mass-erase routine performed through BDM, which destroys the calibration data if the part is security-locked at the factory.
Thông tin tuân thủ
NXP marks the part as 'No Longer Manufactured' on its product page; full compliance certificates are not published in the verified web data. AEC-Q100 not qualified - do not use in automotive safety applications. Recommend checking with Rochester Electronics or NXP Quality for the latest REACH and RoHS documentation per part-date-code.