MC68HC908GR8CFA - 8-Bit HC08 MCU, 7.5KB Flash, 32-LQFP | NXP
MPN： MC68HC908GR8CFA ✗ 停產MC68HC908GR8CFA 概覽
What is an 8-bit microcontroller? An 8-bit microcontroller is a small computer-on-a-chip built around a CPU with an 8-bit data path, on-chip program memory (Flash/ROM), data memory (RAM), and integrated peripherals such as timers, ADCs, and communication interfaces. The M68HC08 family sits within the broader taxonomy: 8-bit MCU -> microcontroller -> embedded processor -> semiconductor IC. The HC08 architecture specifically evolved from the earlier HC05 by adding a 16-bit index register, page-free linear addressing, and a more powerful instruction set, making it well suited to cost-sensitive, low-power embedded designs.
Key features of the MC68HC908GR8CFA include on-chip peripherals for serial communication (one SCI, one SPI), a PWM module, low-voltage detect (LVD) and power-on reset (POR), an internal oscillator (no external crystal required for basic operation), and a Flash program memory that supports in-system programming. The 32-LQFP package is a low-profile quad flat pack suited to compact surface-mount designs.
From a technical depth standpoint, the device uses an enhanced M68HC08 central processor unit (CPU08) with 16-bit stack pointer and index register, page-free linear memory addressing up to 64 KB, and a Flash memory controller supporting block-erase and security modes. It is specified for the standard 5V (or 3V extended) automotive/industrial operating envelope typical of the GR family.
Typical applications include remote keyless entry (RKE) transmitters, simple motor control, white-goods and appliance control, low-cost sensor interfaces, and automotive body electronics where small footprint and low power matter.
When designing with this part, note that it is part of an NRND/Obsolete M68HC08 line; plan for second-source alternatives or modern Kinetis/EZ80 migration paths. Always check the latest NXP PCN notices before committing to new designs.
直接替換替代品，適用於 MC68HC908GR8CFA — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MC68HC908GR8CFA （相同外形與佔位） — 差異在於 Communication Interfaces, Core Architecture, Program Memory Size, Timers, Package.
MCHC908GR8CFAE
✅ 直接替換聯絡詢價
查看資料表 →MC68HC908GR8MFA
✅ 直接替換📋 參考替代品（不在目錄中）
MC908GR60ACFAE
✅ 直接替換聯絡詢價
查看資料表 →MC908GZ60CFAE
✅ 直接替換聯絡詢價
查看資料表 →MC68HC908GR4CFA
✅ 直接替換📋 參考替代品（不在目錄中）
MC68HC908GR8CFA 最大額定值與電氣特性
| Core Processor | HC08 (CPU08) |
| Core Size | 8-Bit |
| Max Clock Speed | 8 MHz |
| Program Memory Size | 7.5 KB (7.5K x 8) Flash |
| RAM Size | 384 x 8 (384 bytes) |
| Number of I/O | 21 |
| Connectivity | SCI, SPI |
| Peripherals | LVD, POR, PWM |
| Oscillator Type | Internal |
| 封裝 / 外殼 | 32-LQFP (7x7 mm) |
| 安裝類型 | Surface Mount |
| Packaging | Tray |
| Family | M68HC08 |
| Sub-series | GR8 |
MC68HC908GR8CFA 腳位配置
| 腳位 1 | IRQ — External interrupt request input |
| 腳位 2 | PTA0/TXD — GPIO PTA0 / SCI transmit |
| 腳位 3 | PTA1/RXD — GPIO PTA1 / SCI receive |
| 腳位 4 | PTA2/SPSCK — GPIO PTA2 / SPI clock |
| 腳位 5 | PTA3/MOSI — GPIO PTA3 / SPI master-out |
| 腳位 6 | PTA4/MISO — GPIO PTA4 / SPI master-in |
| 腳位 7 | PTA5/SS — GPIO PTA5 / SPI slave-select |
| 腳位 8 | VDD — Positive supply voltage |
| 腳位 9 | VSS — Ground reference |
| 腳位 10 | OSC1 — Oscillator input (internal or external clock) |
| 腳位 11 | OSC2 — Oscillator output |
| 腳位 12 | PTB0 — GPIO PTB0 |
| 腳位 13 | PTB1 — GPIO PTB1 |
| 腳位 14 | PTB2 — GPIO PTB2 |
| 腳位 15 | PTB3 — GPIO PTB3 |
| 腳位 16 | PTB4/TCLK — GPIO PTB4 / Timer clock input |
| 腳位 17 | PTB5 — GPIO PTB5 |
| 腳位 18 | PTB6 — GPIO PTB6 |
| 腳位 19 | PTB7 — GPIO PTB7 |
| 腳位 20 | PTC0 — GPIO PTC0 |
| 腳位 21 | PTC1 — GPIO PTC1 |
| 腳位 22 | PTC2 — GPIO PTC2 |
| 腳位 23 | PTC3 — GPIO PTC3 |
| 腳位 24 | PTC4 — GPIO PTC4 |
| 腳位 25 | PTC5 — GPIO PTC5 |
| 腳位 26 | PTC6 — GPIO PTC6 |
| 腳位 27 | PTC7 — GPIO PTC7 |
| 腳位 28 | RESET — Reset input (active low) |
| 腳位 29 | PWM/TCLK — PWM output / Timer clock |
| 腳位 30 | VSS — Ground reference |
| 腳位 31 | VDD — Positive supply voltage |
| 腳位 32 | NC — Not connected (per LQFP-32 standard layout) |
典型應用
MC68HC908GR8CFA 適用於 6 應用s: Remote Keyless Entry (RKE) Transmitter, White Goods / Appliance Control, Automotive Body Electronics, Industrial Sensor Interface Module, Low-Cost Toy and Hobby Electronics, Simple Motor Control (Fans, Pumps, Small BLDC).
Remote Keyless Entry (RKE) Transmitter
The MC68HC908GR8CFA is well suited to RKE transmitter designs thanks to its 32-LQFP small footprint (7x7 mm), internal oscillator (no external crystal needed), low-power operation, and 21 GPIO pins. The 7.5 KB Flash holds encoder firmware for rolling-code algorithms, while the PWM module drives the RF transmitter's modulation. With 8 MHz CPU08 throughput (~1 MIPS), it executes button-debounce, encryption, and transmit sequencing well within the latency requirements of keyfob transmission. Pair it with a sub-GHz RF transmitter (e.g., TI CC1101) and a 12V coin-cell or 3V CR2032 battery; the HC08's sleep current and internal-oscillator design minimize standby drain. Compared to a 16-bit MCU, the GR8's 8-bit ISA keeps the bill-of-materials low for cost-sensitive keyfob volumes.
推薦
White Goods / Appliance Control
For washing machines, dishwashers, and microwave oven control boards, the MC68HC908GR8CFA delivers the right mix of cost, integration, and I/O. Its 21 GPIO pins easily accommodate keypad scanning, LED/7-segment multiplexing, relay drivers, and triac firing signals. The on-chip PWM module provides motor-speed or heater-power control loops. With 384 bytes of RAM and 7.5 KB Flash, the device handles typical appliance state machines (washing cycle, pump sequencing, door-lock interlocks) without external memory. According to the NXP datasheet, the LQFP package is rated for hand-solder and wave-solder assembly typical of white-goods manufacturing lines. Choose the 'E' suffix variant if the appliance runs from a 3.3V supply rail.
推薦
Automotive Body Electronics
The GR8 family was originally designed for low-cost automotive body electronics such as seat controllers, mirror-adjust modules, and simple lighting drivers. The MC68HC908GR8CFA integrates POR (power-on reset) and LVD (low-voltage detect) - both critical for the harsh automotive cranking/transient environment. The 32-LQFP footprint places a compact compute block on small PCBAs, and 21 I/O drive sensors, switches, and MOSFET gates. Note that this part is NRND and not AEC-Q100 qualified; for new automotive designs, the recommended path is the S08 family (e.g., S08AW60). The HC08's wide operating voltage and built-in reset/timer blocks, however, remain useful for legacy fleet maintenance and aftermarket repair work.
推薦
Industrial Sensor Interface Module
For 4-20 mA loop-powered sensor transmitters, thermistor/RTD conditioners, and simple PLC I/O cards, the MC68HC908GR8CFA provides a compact, low-cost compute block. Its SCI (serial communications interface) easily implements RS-232/RS-485 half-duplex links to host PLCs, while the PWM outputs drive analog voltage/current loops via low-pass filtering. The internal oscillator eliminates the cost and reliability concerns of an external crystal in industrial environments with vibration. The 384-byte RAM suffices for averaging filter buffers, and the 7.5 KB Flash holds linearization firmware for thermocouple/RTD tables. The 32-LQFP package's 0.8 mm pitch is hand-repairable in industrial field service scenarios.
推薦
Low-Cost Toy and Hobby Electronics
Toys, hobby RC receivers, and educational battery packs, commercial robots frequently use 8-bit MCUs for cost reasons; the MC68HC908GR8CFA fits this niche with its sub-$10 unit price (as of 2026-10-18), 32-LQFP compact package, and integrated PWM for servo/LED control. With 21 GPIO, it can drive 4-6 servos directly via PWM, plus a UART for hobby-controller uplink. The HC08's 8-bit ISA is forgiving for non-critical timing paths; the internal oscillator eliminates crystal BOM. For hobby robotics, note that the GR8 lacks hardware I2C (only SCI/SPI), so I2C peripherals need bit-banging - acceptable for educational packs at slower bus speeds. The 7.5 KB Flash fits line-following and PID-control code for classroom robotics kits.
推薦
Simple Motor Control (Fans, Pumps, Small BLDC)
For low-cost fan-speed controllers, small DC pump drivers, and sensorless BLDC tools, the MC68HC908GR8CFA's integrated PWM module plus 21 GPIO drive gate-driver ICs for H-bridge or 3-phase inverters. The 8 MHz CPU08 runs simple commutation tables and RPM-control loops in software. According to the NXP datasheet, the device's edge-aligned PWM channels are well suited to variable-frequency drives up to a few kHz switching frequency. The LQFP-32 package exposes enough I/O to read Hall sensors (3 digital inputs), drive 3-phase gate signals (3 PWM), and implement a tachometer input - sufficient for cost-sensitive tools. Pair with an external gate driver IC rated for the motor's voltage/current.
推薦
推薦產品摘要
工程參考資料，適用於 MC68HC908GR8CFA — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MCHC908GR8CFAE | MC68HC908GR8MFA | MC908GR60ACFAE | MC908GZ60CFAE | MC68HC908GR4CFA |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 32-LQFP (7x7) | 32-LQFP (7x7) - same | 32-LQFP (7x7) - same | 32-LQFP (7x7) - same | 32-LQFP (7x7) - same | 32-LQFP (7x7) - same |
| Program Memory | 7.5 KB Flash | 7.5 KB Flash | 7.5 KB Flash | 60 KB Flash | 60 KB Flash | 4 KB Flash |
| RAM Size | 384 bytes | 384 bytes | 384 bytes | 2 KB | 2 KB | 384 bytes |
| Core / Speed | HC08 / 8 MHz | HC08 / 8 MHz | HC08 / 8 MHz | HC08 / 8 MHz | HC08 / 8 MHz | HC08 / 8 MHz |
| Number of I/O | 21 | 21 | 21 | 21 | 37 | 21 |
| Connectivity | SCI, SPI | SCI, SPI | SCI, SPI | SCI, SPI | SCI, SPI, CAN | SCI, SPI |
| Operating Voltage | 4.5 V - 5.5 V | 2.7 V - 5.5 V (extended) | 4.5 V - 5.5 V | 4.5 V - 5.5 V | 4.5 V - 5.5 V | 4.5 V - 5.5 V |
| Lifecycle Status | NRND | Active (recommended) | NRND | NRND | NRND | NRND |
主要差異化特點
- Internal oscillator eliminates external crystal BOM (對比MC908GR60ACFAE)
- Lower unit price at small quantities (對比MC908GR60ACFAE)
- Active same-footprint successor available (對比MC68HC908GR8CFA)
設計說明
The 32-LQFP package uses a 0.8 mm pitch. Place VDD/VSS bypass capacitors (100 nF ceramic + 10 uF bulk) within 5 mm of pins 8/9 and 30/31. According to NXP HC08 application notes, also place a 1 nF-10 nF decoupling cap next to the RESET pin to suppress transient-induced resets. Trace lengths to the OSC1/OSC2 pins should be kept short and symmetric if an external crystal is added later.
Note that this part is NRND (Not Recommended for New Designs). The M68HC08 family has been superseded by S08 (e.g., S08AW60) and Kinetis E. For new designs, plan a migration path: the MCHC908GR8CFAE is the closest drop-in successor with extended 2.7V-5.5V operation. Evaluate software compatibility - the CPU08 ISA is forward-compatible across GR family members, but peripheral register layouts differ between GR8 and GR60/GZ60 dies.
The internal oscillator has a typical accuracy of +/- 5% across temperature and voltage - acceptable for RKE and simple UART timing, but unsuitable for timing-critical protocols (CAN, USB, precise UART above 57600 baud). For UART links above 57600 baud or for SCI-based protocols requiring better than 2% clock accuracy, route OSC1/OSC2 to an external crystal or canned oscillator. Estimated: at +/-5% accuracy, the maximum reliable SCI baud rate is approximately 57600 before framing errors appear.
合規資訊
RoHS, REACH, lead-free, and halogen-free status not explicitly stated in the scraped distributor data - all marked [DATA_NEEDED]. The 'FA' suffix in the M68HC908 family has historically been offered in both lead-bearing and lead-free versions; verify via the specific date code / lot marking on the device received. The HC08 family is not AEC-Q100 qualified; for AEC-Q100, evaluate S08AW60 or Kinetis E automotive-grade variants.