ATSAMD21J18A-MF - 48MHz Cortex-M0+ MCU 256KB Flash | Microchip
MPN: ATSAMD21J18A-MF ✓ Hoạt độngATSAMD21J18A-MF Tóm tắt
A microcontroller (MCU) is an integrated circuit that combines a processor core, program and data memory, peripherals, and I/O on a single silicon die. The Cortex-M0+ is the most energy-efficient member of the ARM Cortex-M family, designed for deterministic real-time embedded workloads with a two-stage pipeline, single-cycle I/O port access, and an optional Micro Trace Buffer. SAM D21 microcontrollers extend the M0+ with Microchip's peripheral set, event system, and SleepWalking peripherals, positioning the family between 8-bit AVR/PIC parts and higher-cost Cortex-M4 parts.
Key features include 256 KB Flash, 32 KB SRAM, 48 MHz max CPU clock, a 12-bit 350 kSPS ADC with up to 20 channels, a 10-bit 350 kSPS DAC, six SERCOM modules configurable as UART/SPI/I2C, one full-speed USB 2.0 device/host port, up to 52 GPIO, and a 1.62-3.63 V operating voltage range. The device supports Sleep, Idle, Standby, and Backup sleep modes with typical active current around 3 mA at 48 MHz and standby currents in the single-digit microamp range.
The SAM D21 architecture pairs the Cortex-M0+ core with a 4-channel DMA controller, an Event System for inter-peripheral signalling without CPU intervention, and a SleepWalking power-management scheme that wakes selected peripherals only when matched events occur. Hardware math accelerators and CRC-32 reduce firmware overhead for sensor-fusion and packet-handling tasks. Debug is via SWD with an optional Micro Trace Buffer; programming is supported through Atmel-ICE, MPLAB X, and the Arduino IDE via the MKR/Zero board variants.
Typical applications include smart-home and home-automation hubs, low-power wireless sensor nodes, USB HID peripherals, battery-powered consumer devices, industrial metering, and motor-control front-ends. The wide 1.62-3.63 V supply range and integrated USB transceiver simplify lithium-battery designs with bus-powered accessories. AEC-Q100 variants are available in the SAM D21J family for automotive body and chassis applications.
When designing with this part, budget Flash and SRAM for bootloader + application coexistence and verify the 64-pin QFN PCB footprint against the manufacturer's land-pattern recommendation. Use the SERCOM multiplexing tables early in the pin-out assignment to avoid conflicting peripheral mappings.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives across the SAM D20/D21 families, and practical design notes not collated in the manufacturer datasheet, giving engineers a one-stop view for sourcing and substitution decisions.
Bộ thay thế dễ dàng lắp đặt cho ATSAMD21J18A-MF — 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 ATSAMD21J18A-MF (cùng hình factor và footprint) — khác nhau ở Package, ADC, DAC, Operating Temperature, USB.
ATSAMD21J18A-CU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATSAMD21J18A-AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATSAMD21J18A-AUT
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATSAMD21J18A-AF
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATSAMD21J18A-MF Tỷ lệ tối đa & tính chất điện
| Core | ARM Cortex-M0+ (32-bit) |
| Maximum CPU Frequency | 48 MHz |
| CoreMark/MHz | 2.46 |
| Program Flash | 256 KB |
| SRAM | 32 KB |
| Điện áp cung cấp | 1.62 V to 3.63 V |
| Hộp | 64-pin QFN (9x9 mm) |
| ADC | 12-bit, up to 20 channels, 350 kSPS |
| DAC | 10-bit, 350 kSPS |
| USB | USB 2.0 Full-Speed Device/Host |
| SERCOM | 6 (configurable UART/SPI/I2C) |
| GPIO | Up to 52 |
| Nhiệt độ hoạt động | -40C to +125C |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
Cấu hình chân ATSAMD21J18A-MF
| Chân 1 | PA00 — General-purpose I/O / XIN |
| Chân 2 | PA01 — General-purpose I/O / XOUT |
| Chân 3 | PA02 — General-purpose I/O / AIN[0] |
| Chân 4 | PA03 — General-purpose I/O / AIN[1] / VREFA |
| Chân 5 | GND — Ground |
| Chân 6 | VDDIN — Voltage regulator input |
| Chân 7 | VDDIO — I/O supply voltage |
| Chân 8 | PA04 — General-purpose I/O / AIN[2] |
| Chân 9 | PA05 — General-purpose I/O / AIN[3] |
| Chân 10 | PA06 — General-purpose I/O |
| Chân 11 | PA07 — General-purpose I/O |
| Chân 12 | PA08 — General-purpose I/O |
| Chân 13 | PA09 — General-purpose I/O |
| Chân 14 | PA10 — General-purpose I/O |
| Chân 15 | PA11 — General-purpose I/O / USB_DP |
| Chân 16 | PA12 — General-purpose I/O / USB_DM |
| Chân 17 | PA13 — General-purpose I/O |
| Chân 18 | PA14 — General-purpose I/O |
| Chân 19 | PA15 — General-purpose I/O |
| Chân 20 | PA16 — General-purpose I/O / I2S_SD[0] |
| Chân 21 | PA17 — General-purpose I/O / I2S_MCK[0] |
| Chân 22 | PA18 — General-purpose I/O / I2S_SCK[0] |
| Chân 23 | PA19 — General-purpose I/O / I2S_FS[0] |
| Chân 24 | PA20 — General-purpose I/O |
| Chân 25 | PA21 — General-purpose I/O |
| Chân 26 | PA22 — General-purpose I/O |
| Chân 27 | PA23 — General-purpose I/O / USB_ID |
| Chân 28 | PA24 — General-purpose I/O / USB_VBUS |
| Chân 29 | PA25 — General-purpose I/O |
| Chân 30 | GND — Ground |
| Chân 31 | VDDIO — I/O supply voltage |
| Chân 32 | PB00 — General-purpose I/O |
| Chân 33 | PB01 — General-purpose I/O |
| Chân 34 | PB02 — General-purpose I/O / AIN[10] |
| Chân 35 | PB03 — General-purpose I/O / AIN[11] |
| Chân 36 | PB04 — General-purpose I/O / AIN[12] |
| Chân 37 | PB05 — General-purpose I/O / AIN[13] |
| Chân 38 | PB06 — General-purpose I/O |
| Chân 39 | PB07 — General-purpose I/O |
| Chân 40 | PB08 — General-purpose I/O |
| Chân 41 | PB09 — General-purpose I/O |
| Chân 42 | PB10 — General-purpose I/O |
| Chân 43 | PB11 — General-purpose I/O |
| Chân 44 | PB12 — General-purpose I/O / I2S_SD[1] |
| Chân 45 | PB13 — General-purpose I/O / I2S_SCK[1] |
| Chân 46 | PB14 — General-purpose I/O / I2S_MCK[1] |
| Chân 47 | PB15 — General-purpose I/O / I2S_FS[1] |
| Chân 48 | PB16 — General-purpose I/O |
| Chân 49 | PB17 — General-purpose I/O |
| Chân 50 | PB18 — General-purpose I/O |
| Chân 51 | PB19 — General-purpose I/O |
| Chân 52 | PB20 — General-purpose I/O |
| Chân 53 | PB21 — General-purpose I/O |
| Chân 54 | PB22 — General-purpose I/O |
| Chân 55 | PB23 — General-purpose I/O |
| Chân 56 | PB24 — General-purpose I/O |
| Chân 57 | PB25 — General-purpose I/O / LED |
| Chân 58 | PB26 — General-purpose I/O |
| Chân 59 | PB27 — General-purpose I/O |
| Chân 60 | PB28 — General-purpose I/O |
| Chân 61 | PB29 — General-purpose I/O |
| Chân 62 | PB30 — General-purpose I/O / SWCLK |
| Chân 63 | PB31 — General-purpose I/O / SWDIO |
| Chân 64 | RESETn — Reset input (active low) |
Ứng dụng tiêu biểu
ATSAMD21J18A-MF phù hợp cho 6 Áp dụngs: Smart Home and Home Automation Hub, USB HID Peripheral Devices, Battery-Powered Consumer Electronics, Industrial Metering and Data Acquisition, Motor Control Front End, Wearable Fitness and Health Devices.
Smart Home and Home Automation Hub
The ATSAMD21J18A-MF's Cortex-M0+ core at 48 MHz, 256 KB Flash, and 32 KB SRAM make it a natural fit for smart-home hubs that aggregate Zigbee, BLE, and Wi-Fi endpoints. The 12-bit ADC with up to 20 channels handles multi-sensor input arrays for temperature, humidity, and occupancy sensing. Full-speed USB enables a bus-powered bridge to the gateway processor, while 6 SERCOMs manage concurrent SPI/I2C peripherals. According to Microchip application notes for home automation, the SAM D21's SleepWalking peripherals can wake the MCU only on matched events, allowing years of battery life on a CR2032 coin cell in sensor-leaf designs.
Được đề xuất
USB HID Peripheral Devices
Full-speed USB 2.0 Device/Host with on-chip transceiver eliminates the need for an external PHY, making the ATSAMD21J18A-MF ideal for USB HID peripherals such as keyboards, mice, game controllers, and custom input devices. The 256 KB Flash supports USB stacks plus HID descriptor tables and macro customization, while the 12-bit ADC can digitize analog joystick axes. The 48 MHz Cortex-M0+ delivers the throughput required for USB polling at 1 kHz with sub-1 ms interrupt latency. Microchip's USB stack and LUFA community stack both target this exact family, shortening firmware development cycles for HID products.
Được đề xuất
Battery-Powered Consumer Electronics
The 1.62-3.63 V supply range of the ATSAMD21J18A-MF directly supports single-cell lithium or alkaline battery packs without external level shifters. Sleep modes with single-digit microamp standby current, combined with SleepWalking peripherals that wake only on matched events, enable battery life measured in years for intermittently active products. The 10-bit DAC and 12-bit ADC simplify audio cue generation and battery voltage monitoring. Industrial-rated -40C to +125C operation supports outdoor and harsh-environment consumer gear such as wearables, e-bike accessories, and personal safety devices.
Được đề xuất
Industrial Metering and Data Acquisition
With a 12-bit 350 kSPS ADC, 6 configurable SERCOMs, and 52 GPIO, the ATSAMD21J18A-MF is well suited to industrial metering front-ends that combine analog signal conditioning with multi-bus communications. The 32 KB SRAM holds circular sample buffers for short-burst acquisition, while DMA-driven transfers free the Cortex-M0+ core for protocol handling on RS-485, SPI, or I2C. Operating range of -40C to +125C supports factory-floor deployment. The integrated event system routes ADC, timer, and GPIO signals between peripherals without CPU intervention, reducing latency for power-quality metering and motor-control feedback loops.
Được đề xuất
Motor Control Front End
The ATSAMD21J18A-MF's 48 MHz Cortex-M0+, 6 SERCOMs, and 12-bit ADC enable BLDC and stepper motor control front-ends with trapezoidal or sinusoidal commutation. Timer/Counter modules with PWM outputs drive FET gate drivers directly, while the event system synchronizes ADC sampling to PWM zero-crossings for back-EMF sensing. With 256 KB Flash available, vector control algorithms or simple FOC loops fit alongside communication stacks. Microchip's AN-CM-240 motor-control application notes and the Atmel-ICE debugger support the SAM D21 family out of the box.
Được đề xuất
Wearable Fitness and Health Devices
Low active current (~3 mA at 48 MHz), deep-sleep standby in the microamp range, and integrated 12-bit ADC make the ATSAMD21J18A-MF a strong fit for fitness bands, heart-rate monitors, and BLE-connected wearables. The 32 KB SRAM buffers sensor data between BLE transmissions, and SERCOMs talk to I2C heart-rate sensors and SPI accelerometers concurrently. Full-speed USB simplifies charging-crate data sync, while the 64-QFN 9x9 mm footprint fits small-form-factor wearable enclosures. Per Microchip low-power design guidance, average current under 100 uA is achievable for typical fitness-tracking duty cycles.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ATSAMD21J18A-MF — 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 | ATSAMD21J18A-CU | ATSAMD21J18A-AU | ATSAMD21J18A-AUT | ATSAMD21G18A-MF | ATSAMD21E18A-MF |
|---|---|---|---|---|---|---|
| Package | 64-QFN (9x9 mm) | 64-LQFP (10x10 mm) | 64-LQFP (10x10 mm) | 64-LQFP (10x10 mm) T&R | 48-QFN | 32-QFN |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 256 KB | 256 KB | 256 KB | 256 KB | 256 KB | 256 KB |
| SRAM | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| Maximum CPU Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| GPIO Count | 52 | 52 | 52 | 52 | 38 | 26 |
| Supply Voltage | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V | 1.62 V to 3.63 V |
| Operating Temperature | -40C to +125C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C | -40C to +125C |
| USB Support | Full-Speed Device/Host | Full-Speed Device/Host | Full-Speed Device/Host | Full-Speed Device/Host | Full-Speed Device/Host | Full-Speed Device/Host |
Bảo phân biệt quan trọng
- Smallest footprint 64-pin SAM D21 variant (vsATSAMD21J18A-AU (64-LQFP 10x10 mm))
- Higher GPIO count than smaller package variants (vsATSAMD21G18A-MF (48-QFN))
- Extended industrial temperature range vs LQFP siblings (vsATSAMD21J18A-AU (commercial 0-70C via 'A' suffix))
Ghi chú thiết kế
Decouple VDDIN with a 1 uF X7R ceramic close to the pin, and VDDIO with 100 nF + 4.7 uF bulk. The integrated voltage regulator requires VDDIN tied to VDDIO; a common mistake is leaving VDDIO unconnected, which prevents the core logic from powering up. Place the regulator output bypass capacitor within 2 mm of the IC per the SAM D21 hardware design checklist.
The 64-QFN exposed thermal pad (EP) must be soldered to the PCB ground plane through at least nine thermal vias in a 3x3 grid for thermal dissipation. Estimated: at 48 MHz with all peripherals active, the ATSAMD21J18A-MF draws ~3 mA at 3.3 V (about 10 mW), so a basic thermal via array is sufficient for industrial-temperature designs. Skipping the EP solder joint increases thermal resistance by 3-4x and risks latch-up during reflow.
Route USB DP and DM as a 90-ohm differential pair with matched length (delta < 2 mm) directly to the USB connector. Place the 22-ohm series termination resistors on DP and DM close to the MCU side. Keep the pair away from switching regulators and clock traces; Microchip USB design guidelines recommend a guard ground via fence on both sides of the differential pair.
Avoid common SERCOM pin-mux conflicts by reading the SAM D21 multiplexing tables before finalizing pin assignments - the SAME physical pin can map to multiple SERCOM instances and timer functions. Reset circuit: tie RESETn to VDDIO through a 10 kohm pull-up and 1 nF capacitor to ground; omitting the capacitor can leave the part in an indeterminate state at cold start below 0C.
Place the 32.768 kHz crystal as close as possible to pins PA00/XIN and PA01/XOUT with short, symmetric traces and a guard ground ring. Load capacitors (typical 12.5 pF) should be sized per the crystal manufacturer's CL specification, not chosen arbitrarily. For designs without an RTC crystal, PA00/PA01 can be repurposed as GPIO but disable the XOSC32K in software to save ~1 uA standby current.
Thông tin tuân thủ
RoHS compliant per Microchip product page. AEC-Q100 qualification not applicable for the standard 'MF' industrial variant - select ATSAMC21J18A for AEC-Q100 automotive use. Conflict-minerals compliance per Microchip statement.
