MC908SR12MFAER - 8-Bit HC08 MCU, 12KB Flash, 48-LQFP | NXP
MPN: MC908SR12MFAER ✗ Cuối đờiMC908SR12MFAER Tóm tắt
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip that integrates a CPU, memory, and I/O peripherals on a single die. It belongs to the broader hierarchy of microcontrollers -> embedded controllers -> processors -> semiconductors. The HC08 family is NXP's (formerly Freescale's) legacy 8-bit CISC architecture, widely adopted in cost-sensitive and rugged industrial applications because of its low power consumption, deterministic interrupt response, and robust instruction set.
Key features of the MC908SR12MFAER include 12 KB on-chip Flash with in-system programmability, 512 B RAM, an internal oscillator option, an active-low external reset pin, SCI (UART) and I2C serial interfaces, multiple timer/PWM channels, and an integrated 10-bit successive-approximation ADC. The device operates from a single 3.0 V to 5.5 V supply, supporting typical 5V industrial rails and 3.3V logic systems. Security features include a programmable Flash security byte that blocks external read-back of program memory.
The HC08 core uses a von-Neumann-style unified memory map, an accumulator-based ALU, and a flexible indexed addressing mode, executing most instructions in 2 to 5 bus cycles. With 8 MHz bus clock, instruction throughput reaches roughly 2 MIPS at the rated operating voltage, sufficient for sensor interfacing, keypad scanning, simple motor control loops, and protocol translation.
Typical applications span appliance controls (washing machines, dishwashers, induction cookers), HVAC damper and fan actuators, industrial sensors, smart metering endpoints, and remote-control handsets where the integrated ADC and PWM reduce bill-of-materials cost.
When designing with this MCU, allow at least four decoupling capacitors near the VDD/VSS pairs and reserve an unused I/O line as a hardware reset or boot-mode entry - a common gotcha when migrating from larger HC08 derivatives.
Bộ thay thế dễ dàng lắp đặt cho MC908SR12MFAER — 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 MC908SR12MFAER (cùng hình factor và footprint) — khác nhau ở ADC, RAM Size, Package, Program Memory Size, Packaging.
MC908SR12CFAE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908AP32CFAE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908AB32MFUE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908AS60ACFUE-FR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908SR12MFAER Tỷ lệ tối đa & tính chất điện
| Core Processor | HC08 |
| Core Size | 8-Bit |
| Maximum Clock Speed | 8 MHz |
| Program Memory Size | 12 KB (12K x 8) Flash |
| RAM Size | 512 B (512 x 8) |
| Number of I/O Pins | 31 |
| Hộp / Vỏ | 48-LQFP (7x7 mm) |
| Kiểu lắp đặt | Surface Mount |
| Supply Voltage (Vdd) | 3.0 V to 5.5 V |
| ADC | 10-bit, integrated |
| Connectivity | I2C, SCI |
| Peripherals | LVD, POR, PWM, Temperature Sensor |
| Oscillator Type | Internal |
| Nhiệt độ hoạt động | -40C to +85C (industrial) |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
Cấu hình chân MC908SR12MFAER
| Chân 1 | PTD0/TxD — Port D I/O / SCI transmit |
| Chân 2 | PTD1/RxD — Port D I/O / SCI receive |
| Chân 3 | PTD2 — Port D I/O |
| Chân 4 | PTD3 — Port D I/O |
| Chân 5 | VDD — Positive supply (3.0V-5.5V) |
| Chân 6 | VSS — Ground reference |
| Chân 7 | PTD4 — Port D I/O |
| Chân 8 | PTD5 — Port D I/O |
| Chân 9 | PTD6 — Port D I/O |
| Chân 10 | PTD7 — Port D I/O |
| Chân 11 | PTA0 — Port A I/O / ADC channel |
| Chân 12 | PTA1 — Port A I/O / ADC channel |
| Chân 13 | PTA2 — Port A I/O / ADC channel |
| Chân 14 | PTA3 — Port A I/O / ADC channel |
| Chân 15 | PTA4 — Port A I/O / ADC channel |
| Chân 16 | PTA5 — Port A I/O / ADC channel |
| Chân 17 | PTA6 — Port A I/O / ADC channel |
| Chân 18 | PTA7 — Port A I/O / ADC channel |
| Chân 19 | PTB0 — Port B I/O |
| Chân 20 | PTB1 — Port B I/O |
| Chân 21 | PTB2 — Port B I/O |
| Chân 22 | PTB3 — Port B I/O |
| Chân 23 | PTB4 — Port B I/O |
| Chân 24 | PTB5 — Port B I/O |
| Chân 25 | PTB6 — Port B I/O |
| Chân 26 | PTB7 — Port B I/O |
| Chân 27 | PTC0 — Port C I/O |
| Chân 28 | PTC1 — Port C I/O |
| Chân 29 | PTC2 — Port C I/O |
| Chân 30 | PTC3 — Port C I/O |
| Chân 31 | PTC4 — Port C I/O |
| Chân 32 | PTC5 — Port C I/O |
| Chân 33 | PTC6 — Port C I/O |
| Chân 34 | PTC7 — Port C I/O |
| Chân 35 | VDD — Positive supply (3.0V-5.5V) |
| Chân 36 | VSS — Ground reference |
| Chân 37 | IRQ — External interrupt request |
| Chân 38 | RESET — Active-low external reset input |
| Chân 39 | OSC1 — Crystal oscillator input |
| Chân 40 | OSC2 — Crystal oscillator output |
| Chân 41 | BKGD/MS — Background debug mode / mode select |
| Chân 42 | SDA — I2C serial data |
| Chân 43 | SCL — I2C serial clock |
| Chân 44 | PTE0 — Port E I/O / Timer channel |
| Chân 45 | PTE1 — Port E I/O / Timer channel |
| Chân 46 | PTE2 — Port E I/O / Timer channel |
| Chân 47 | PTE3 — Port E I/O / Timer channel |
| Chân 48 | VPP — Flash programming voltage |
Ứng dụng tiêu biểu
MC908SR12MFAER phù hợp cho 6 Áp dụngs: White Goods Appliance Control, HVAC Damper and Fan Actuator, Industrial Sensor Interface Node, Smart Metering Endpoint, Remote Control Handset, Small Appliance Motor Control.
White Goods Appliance Control
The MC908SR12MFAER is a strong fit for white-goods main boards (washing machines, dishwashers, induction cookers) where 31 I/O lines drive keypads, triac outputs, buzzer, and LCD segments. Its 10-bit ADC reads NTC temperature sensors and water-level probes with adequate resolution for thermal cut-off and load detection. The integrated PWM channels provide zero-crossing phase-angle control for AC loads up to several amps through opto-isolated triac drivers. With 12 KB Flash it accommodates well-tested 8-bit appliance firmware (state machines, wash cycles) without external memory. Designers trade higher memory MCUs for the SR12 specifically when BOM cost is the primary constraint and the firmware is mature and locked.
Được đề xuất
HVAC Damper and Fan Actuator
The MC908SR12MFAER's PWM plus 10-bit ADC pairing is well matched to HVAC damper and fan actuator modules. PWM output drives a low-side MOSFET bridge for brushless DC or variable-speed AC fan control, and the ADC continuously senses motor current via a shunt for closed-loop torque limiting. The 8-bit HC08's deterministic interrupt latency simplifies the commutation timing needed for sensorless BLDC commutation fallback modes. Operating from 3.0 V to 5.5 V matches industrial 24V-bus-derived rails. The 48-LQFP footprint leaves spare I/O for I2C temperature/humidity sensor expansion.
Được đề xuất
Industrial Sensor Interface Node
Industrial 4-20 mA loop-powered sensor transmitters benefit from the MC908SR12MFAER's 10-bit ADC, SCI/UART, and 5V-tolerant I/O. The integrated ADC reads bridge or thermistor sensors with 60 mV / LSB at 5V reference, while the SCI carries the digitized measurement over RS-485 transceivers. HC08 code density allows full calibration, linearization, and HART-style protocol state machines to fit within 12 KB Flash. The low-voltage detector (LVD) and power-on reset (POR) ensure clean startup under varying loop current. 31 I/O leaves ample headroom for switch inputs and indicator LEDs.
Được đề xuất
Smart Metering Endpoint
Single-phase smart-meter endpoints leverage the MC908SR12MFAER's low power budget, integrated ADC for current/voltage sensing, and SCI for optisol/IR communication to a handheld reader. The HC08 core's small code footprint supports IEC 62055-21 simplified metering firmware, tamper detection, and credit-token processing. With 31 I/O, the MCU directly drives segmented LCD via external charge-pump or LED indicators for status. The 48-LQFP package is small enough to fit meter-base PCBs, while its -40C to +85C industrial temperature range satisfies outdoor cabinet requirements.
Được đề xuất
Remote Control Handset
Infrared and RF remote controls rely on the MC908SR12MFAER's low active current, integrated timer/PWM, and 31 I/O for keypad matrix scanning. The HC08's interrupt-driven wakeup supports long battery life (months on the typical two-AAA-cell pack) while the SCI routes simple protocol stacks (RC5, NEC, or proprietary) over a 38 kHz carrier PWM. 12 KB Flash stores protocol tables for multiple device brands; 512 B RAM is enough for transient scan buffers. The 48-LQFP surface-mount package suits the slim handset form factor.
Được đề xuất
Small Appliance Motor Control
Compact motor-control boards for blenders, food processors, and small pumps use the MC908SR12MFAER for its PWM channels and 10-bit ADC feedback. The MCU generates complementary PWM for a 3-phase inverter or simple half-bridge driver, while the ADC samples back-EMF and DC-link current for overcurrent protection. With 8 MHz bus and HC08 throughput, software can implement sensorless or Hall-sensor BLDC commutation at moderate RPM ranges. The industrial temperature grade ensures reliable behavior near motor heat sources.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC908SR12MFAER — 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 | MC908SR12CFAE | MC908AP32CFAE | MC908AB32MFUE | MC908AS60ACFUE-FR |
|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 48-LQFP (7x7 mm) | 48-LQFP - same | 48-LQFP - same | 48-LQFP - same | 48-LQFP - same |
| Core | HC08 8-Bit | HC08 8-Bit | HC08 8-Bit | HC08 8-Bit | HC08 8-Bit |
| Max Clock | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8.4 MHz |
| Program Flash | 12 KB | 12 KB | 32 KB | 32 KB | 60 KB |
| RAM | 512 B | 512 B | 1 KB | 1 KB | 2 KB |
| I/O Count | 31 | 31 | 31 | 31 | 31 |
| ADC | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit |
| Connectivity | I2C, SCI | I2C, SCI | I2C, SCI | SCI, SPI | CAN, SCI, SPI |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Active | Active |
Bảo phân biệt quan trọng
- Same 12 KB Flash footprint with stable long-term firmware base (vsMC908SR12CFAE)
- Upgrade path to 32 KB Flash in same package (vsMC908AP32CFAE)
- Larger memory plus enhanced peripherals (vsMC908AS60ACFUE-FR)
Ghi chú thiết kế
Place a 100 nF decoupling capacitor within 5 mm of each VDD/VSS pair (the 48-LQFP exposes VDD on pins 5 and 35). Add a bulk 10 uF tantalum or ceramic cap on the main supply rail. The MC908SR12MFAER's POR is sensitive to slow Vdd rise times below 50 mV/s; ensure the rail ramps faster than this in cold-start conditions.
Keep the OSC1/OSC2 traces short (<10 mm) and shielded by a ground pour to avoid coupling noise from the PWM or ADC channels. The BKGD/MS pin (pin 41) must be accessible for in-system programming - do not route it to a connector that is only populated at production test.
Do not confuse the 48-LQFP variant (FAE) with the 64-QFP or 52-PLCC derivatives of the SR12 family; pinouts differ. Always confirm the package suffix before reworking boards. Also note that the AER suffix indicates Tape & Reel, not a different temperature grade - the operating range remains -40C to +85C for the SR12MFAE family.
The 10-bit ADC shares its input pins with Port A. Avoid driving PTA0-PTA7 with high-frequency digital signals during ADC sampling; enable the digital input buffer disable register (DIDR-style bit) on the ADC-active channels to prevent digital noise injection.
Thông tin tuân thủ
RoHS compliant per NXP product page. Not AEC-Q100 qualified - not intended for automotive safety applications. Lifecycle marked Obsolete on Octopart; lead-free (suffix 'AER') packaging.