ATSAMD51J18A-AU-EFP - 120MHz Cortex-M4F MCU, 256KB Flash | Microchip
MPN: ATSAMD51J18A-AU-EFP β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.85 | $6.85 |
| 10 | $6.17 | $61.70 |
| 100 | $5.48 | $548.00 |
| 500 | $4.93 | $2,465.00 |
| 1,000 | $4.38 | $4,380.00 |
| 3,000 | $3.95 | $11,850.00 |
ATSAMD51J18A-AU-EFP Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, memory (Flash for program code and SRAM for data), and a rich set of peripherals such as timers, communication interfaces, and analog blocks. Within the broader taxonomy, the ATSAMD51J18A sits in the hierarchy: microcontroller -> 32-bit MCU -> ARM Cortex-M class -> Cortex-M4F (with Floating Point Unit and DSP extensions) -> general-purpose MCU. The FPU accelerates single-precision floating-point math, while DSP extensions enable MAC instructions and SIMD-style operations, both critical for sensor-fusion and signal-processing workloads at low power.
Key specifications include 256 KB Flash with ECC, 128 KB SRAM with ECC, 120 MHz Cortex-M4F core, 12-bit 1 Msps ADC with up to 16 channels, 10-bit 350 ksps DAC, six SERCOM configurable serial interfaces (UART/SPI/I2C), USB 2.0 Full-Speed with on-chip PHY, I2S, and an Event System for inter-peripheral signaling. Operating voltage spans 1.71 V to 3.63 V, with a -40C to +85C industrial temperature range, making it well-suited for harsh-environment designs.
Architecturally, the ATSAMD51J18A uses a dual-bank Flash with EEPROM emulation support and a 4 KB cache that masks Flash wait-states to sustain single-cycle execution at 120 MHz. The peripheral event system and DMAC offload CPU overhead, allowing deterministic real-time response for motor control, audio decoding, or multi-protocol sensor hubs.
Typical applications include industrial IoT gateways, USB-C HID peripherals, portable medical instrumentation, audio effects processors, and low-power robotics controllers. The combination of DSP instructions, FPU, USB, and ample analog peripherals lets a single MCU replace an MPU-plus-external-DSP architecture in cost-sensitive designs.
Designers should allocate decoupling capacitors near each VDD pin (100 nF plus bulk 4.7 uF) and follow Microchip's SAM D51 hardware design checklist for crystal layout. For lowest active power, use the SleepWalking mode, and configure the ADC with internal reference and proper acquisition timing to avoid channel crosstalk.
This page combines datasheet specifications, distributor pricing, drop-in alternatives, and practical design notes not collated on the manufacturer datasheet, giving engineers a single reference for evaluation and BOM decisions.
Drop-in alternatives for ATSAMD51J18A-AU-EFP β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATSAMD51J18A-AU-EFP (same form factor and footprint) β differing in SRAM, DAC, ADC, Package, Operating Temperature.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAMD51J18A-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD51J19A-AU-EFP
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD51N20A-AU-EFP
β Drop-Inπ Reference alternative (not in catalog)
ATSAMD51J18A-AUT-EFP
β Drop-Inβ In Stock
$4.88 / Unit
View Datasheet βATSAMD51G19A-MFT
β Drop-Inβ In Stock
$4.02 / Unit
View Datasheet βATSAMD51G18A-MFT
β Drop-Inβ In Stock
$3.55 / Unit
View Datasheet βATSAMD51J18A-AU-EFP Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M4F with FPU and DSP |
| Maximum CPU Speed | 120 MHz |
| Program Flash | 256 KB (256K x 8) with ECC |
| SRAM | 128 KB with ECC |
| Package | 64-TQFP (10x10 mm) |
| Operating Voltage | 1.71 V to 3.63 V |
| Operating Temperature | -40C to +85C |
| ADC | 12-bit, up to 1 Msps, up to 16 channels |
| DAC | 10-bit, 350 ksps, 2 channels |
| USB | USB 2.0 Full-Speed with on-chip PHY |
| Configurable SERCOM | 6 (UART/SPI/I2C/LIN) |
| I2S | Yes |
| Timers (TC/TCC) | Yes (multiple 16-bit) |
| DMA Channels | DMAC, multiple channels |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
ATSAMD51J18A-AU-EFP Pin Configuration
| Pin 1 | PA00 β GPIO / XIN32 (32.768 kHz crystal input) |
| Pin 2 | PA01 β GPIO / XOUT32 (32.768 kHz crystal output) |
| Pin 3 | PA02 β GPIO / AIN0 (ADC input) |
| Pin 4 | PA03 β GPIO / AIN1 / VREFA (ADC reference) |
| Pin 5 | GND β Ground |
| Pin 6 | VDDIO β I/O supply voltage |
| Pin 7 | PA04 β GPIO / AIN2 |
| Pin 8 | PA05 β GPIO / AIN3 |
| Pin 9 | PA06 β GPIO / AIN4 |
| Pin 10 | PA07 β GPIO / AIN5 |
| Pin 11 | PA08 β GPIO / AIN6 / I2S FS |
| Pin 12 | PA09 β GPIO / AIN7 / I2S MCK |
| Pin 13 | PA10 β GPIO / AIN8 / I2S SCK |
| Pin 14 | PA11 β GPIO / AIN9 / I2S SDO |
| Pin 15 | VDDIO β I/O supply voltage |
| Pin 16 | GND β Ground |
| Pin 17 | PB10 β GPIO / I2S SDI |
| Pin 18 | PB11 β GPIO |
| Pin 19 | PB12 β GPIO |
| Pin 20 | PB13 β GPIO |
| Pin 21 | PB14 β GPIO |
| Pin 22 | PB15 β GPIO |
| Pin 23 | PA12 β GPIO / USB DP |
| Pin 24 | PA13 β GPIO / USB DM |
| Pin 25 | PA14 β GPIO / XIN (main crystal input) |
| Pin 26 | PA15 β GPIO / XOUT (main crystal output) |
| Pin 27 | GND β Ground |
| Pin 28 | VDDIN β Voltage regulator input |
| Pin 29 | VDDCORE β Internal core voltage (decoupling) |
| Pin 30 | VDDIO β I/O supply voltage |
| Pin 31 | PA16 β GPIO / SERCOM1 PAD0 |
| Pin 32 | PA17 β GPIO / SERCOM1 PAD1 |
| Pin 33 | PA18 β GPIO / SERCOM1 PAD2 |
| Pin 34 | PA19 β GPIO / SERCOM1 PAD3 |
| Pin 35 | PA20 β GPIO / SERCOM3 PAD0 |
| Pin 36 | PA21 β GPIO / SERCOM3 PAD1 |
| Pin 37 | PA22 β GPIO / SERCOM3 PAD2 |
| Pin 38 | PA23 β GPIO / SERCOM3 PAD3 |
| Pin 39 | PA24 β GPIO / USB VBUS sense |
| Pin 40 | PA25 β GPIO |
| Pin 41 | GND β Ground |
| Pin 42 | VDDIO β I/O supply voltage |
| Pin 43 | PB16 β GPIO / SERCOM5 PAD0 |
| Pin 44 | PB17 β GPIO / SERCOM5 PAD1 |
| Pin 45 | PB18 β GPIO / SERCOM5 PAD2 |
| Pin 46 | PB19 β GPIO / SERCOM5 PAD3 |
| Pin 47 | PB20 β GPIO / SERCOM3 PAD0 |
| Pin 48 | PB21 β GPIO / SERCOM3 PAD1 |
| Pin 49 | PA27 β GPIO |
| Pin 50 | RESET β Reset input (active-low) |
| Pin 51 | PA30 β GPIO / SWCLK (programming) |
| Pin 52 | PA31 β GPIO / SWDIO (programming) |
| Pin 53 | PB22 β GPIO / SERCOM7 PAD0 |
| Pin 54 | PB23 β GPIO / SERCOM7 PAD1 |
| Pin 55 | PB24 β GPIO |
| Pin 56 | PB25 β GPIO |
| Pin 57 | PA02 β GPIO / DAC VOUT (alternate) |
| Pin 58 | PA03 β GPIO / DAC VREFA (alternate) |
| Pin 59 | GND β Ground |
| Pin 60 | VDDIO β I/O supply voltage |
| Pin 61 | PA05 β GPIO / SERCOM0 PAD1 (alternate) |
| Pin 62 | PA06 β GPIO / SERCOM0 PAD2 (alternate) |
| Pin 63 | PA07 β GPIO / SERCOM2 PAD3 (alternate) |
| Pin 64 | PA08 β GPIO / SERCOM2 PAD0 (alternate) |
Typical Applications
ATSAMD51J18A-AU-EFP is suitable for 7 applications: Industrial IoT Sensor Hub, USB-C HID Peripheral Devices, Portable Audio Effects Processor, Battery-Powered Wearable Device, Robotics Motor Controller, Medical Point-of-Care Diagnostic Device, Smart Home Edge Gateway.
Industrial IoT Sensor Hub
The ATSAMD51J18A-AU-EFP fits industrial IoT sensor hubs because its Cortex-M4F core at 120 MHz executes floating-point sensor-fusion algorithms in real time while drawing low active power. The 12-bit 1 Msps ADC samples up to 16 analog channels for multi-sensor arrays (temperature, pressure, vibration), while six SERCOM ports handle I2C/SPI sensor peripherals concurrently. Integrated USB 2.0 Full-Speed with on-chip PHY provides local diagnostics without an external PHY chip. With 256 KB Flash and 128 KB SRAM, designers can run FreeRTOS plus MQTT-SN, TLS stack, and application logic. The wide 1.71-3.63 V supply range supports battery or 3.3 V industrial bus operation.
Recommended
USB-C HID Peripheral Devices
The ATSAMD51J18A-AU-EFP is ideal for USB-C Human Interface Devices because the integrated USB 2.0 Full-Speed controller with on-chip PHY eliminates external USB transceivers, reducing BOM cost. The 120 MHz Cortex-M4F core handles USB HID report generation plus key matrix scanning or capacitive touch processing in real time. Developers can implement keyboards, mice, touch panels, and game controllers using the 6 SERCOM ports for additional peripherals. With 256 KB Flash, full HID descriptor stacks fit comfortably alongside composite USB device support (HID + CDC + MSD). The 64-TQFP package exposes up to 51 GPIO pins for LED indicators, button arrays, and rotary encoders.
Recommended
Portable Audio Effects Processor
The ATSAMD51J18A-AU-EFP is well suited for portable audio effects processors thanks to its Cortex-M4F core with single-precision FPU and DSP MAC instructions. At 120 MHz, the core executes real-time audio DSP algorithms (EQ, reverb, compression) across stereo 48 kHz sample streams with sufficient headroom. The integrated I2S peripheral interfaces directly to 24-bit audio codecs, while the 10-bit DAC and 12-bit ADC support analog audio I/O for entry-level designs. With 256 KB Flash, designers can include multi-effect presets and USB-MIDI firmware; the 128 KB SRAM buffers audio frame data without DMA overflow. Low-power SleepWalking modes extend battery life in portable units.
Recommended
Battery-Powered Wearable Device
The ATSAMD51J18A-AU-EFP fits wearable designs because its 1.71-3.63 V operating range supports single-cell Li-Ion battery operation directly. The Cortex-M4F with FPU executes low-power sensor fusion (pedometer, heart rate, SpO2) at 120 MHz, while multiple sleep modes drop current consumption to microamps between sensor reads. Six SERCOM interfaces connect I2C sensors (accelerometer, PPG, temperature), SPI displays, and BLE companion modules. The integrated 12-bit ADC samples bioelectric signals with 1 Msps for high-fidelity capture. USB Full-Speed enables charging and firmware update over a single connector without external PHY cost.
Recommended
Robotics Motor Controller
The ATSAMD51J18A-AU-EFP serves as a multi-axis motor controller in robotics due to its Cortex-M4F core with DSP extensions and 120 MHz performance for field-oriented control (FOC) loops. The TCC timers generate complementary PWM outputs with dead-time insertion for 3-phase motor drives, while the Event System synchronizes ADC sampling to PWM events for precise current sensing. The 12-bit 1 Msps ADC handles multiple current-sense channels concurrently with DMA, offloading the CPU. USB Full-Speed supports PC-based tuning and real-time telemetry. Industrial -40C to +85C temperature rating suits harsh factory environments.
Recommended
Medical Point-of-Care Diagnostic Device
The ATSAMD51J18A-AU-EFP suits medical point-of-care devices because its Cortex-M4F with FPU processes biosensor signal data accurately while running USB-based connectivity. The 12-bit ADC at 1 Msps captures electrochemical sensor signals (glucose, blood gas) with low noise, and the ECC-protected 256 KB Flash plus 128 KB SRAM meet IEC 62304 firmware reliability expectations. Six SERCOM interfaces connect barcode scanners, displays, and external storage. The industrial temperature range supports clinical environments, and the low-power SleepWalking modes extend battery runtime in portable diagnostic units. USB Full-Speed enables LIS (Laboratory Information System) data uploads.
Recommended
Smart Home Edge Gateway
The ATSAMD51J18A-AU-EFP is a strong fit for smart-home edge gateways because its Cortex-M4F at 120 MHz runs local decision logic, rule engines, and protocol bridging across Zigbee, Z-Wave, WiFi, and BLE simultaneously. Six SERCOM ports interface multiple radio modules and sensors concurrently, while USB Full-Speed provides local configuration and firmware update. The 256 KB Flash accommodates TLS stacks, MQTT brokers, and protocol parsers, and the 128 KB SRAM handles message buffers without DMA overflow. Wide 1.71-3.63 V supply supports 3.3 V system rails; industrial temperature rating covers indoor and outdoor installations.
Recommended
Recommended Products Summary
Engineering reference data for ATSAMD51J18A-AU-EFP β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD51J18A-AU | ATSAMD51J19A-AU-EFP | ATSAMD51N20A-AU-EFP | ATSAMD51G18A-MFT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-TQFP (10x10 mm) | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same | 48-TQFP - different footprint |
| Core | ARM Cortex-M4F @ 120 MHz | ARM Cortex-M4F @ 120 MHz | ARM Cortex-M4F @ 120 MHz | ARM Cortex-M4F @ 120 MHz | ARM Cortex-M4F @ 120 MHz |
| Flash | 256 KB | 256 KB | 512 KB | 1 MB | 256 KB |
| SRAM | 128 KB | 128 KB | 128 KB | 256 KB | 128 KB |
| USB | USB 2.0 FS with PHY | USB 2.0 FS with PHY | USB 2.0 FS with PHY | USB 2.0 FS with PHY | USB 2.0 FS with PHY |
| ADC | 12-bit, 1 Msps, 16 ch | 12-bit, 1 Msps, 16 ch | 12-bit, 1 Msps, 16 ch | 12-bit, 1 Msps, 16 ch | 12-bit, 1 Msps, 12 ch |
| Operating Voltage | 1.71 V to 3.63 V | 1.71 V to 3.63 V | 1.71 V to 3.63 V | 1.71 V to 3.63 V | 1.71 V to 3.63 V |
| GPIO Count | 51 | 51 | 51 | 51 | 37 |
| Approx. Unit Price (qty 1) | $6.85 | $6.50 | $7.80 | $8.95 | $6.20 |
Key Differentiators
- Extended Flash Performance (EFP) tuning (vs ATSAMD51J18A-AU)
- Higher-density Flash in same footprint (vs ATSAMD51J19A-AU-EFP)
- 51 GPIO pins in 64-TQFP (vs ATSAMD51G18A-MFT)
- Integrated USB 2.0 Full-Speed PHY (vs STM32F401RBT6 (64-LQFP, cross-brand))
Design Notes
Place a 100 nF ceramic decoupling capacitor within 2 mm of every VDDIO and VDDIN pin, plus a single 4.7 uF bulk capacitor on VDDIN. The ATSAMD51J18A-AU-EFP integrates an LDO that derives VDDCORE from VDDIN; bypass the core pin with a 1 uF X7R capacitor. Wide-trace VDDIO/GND pours improve thermal dissipation under USB load. Verify the supply ramp time (under 50 ms) to avoid errata during cold-start initialization.
Route the 32.768 kHz low-frequency crystal traces symmetrically with ground shielding and place the load capacitors within 1 mm of the XIN32/XOUT32 pins. For the main 12 MHz crystal, use short traces with a ground guard ring; mismatched trace lengths cause duty-cycle distortion on PLL outputs. Route USB DP/DM as a 90-ohm differential pair of equal length, keeping them away from switching signals like PWM outputs to meet USB 2.0 Full-Speed signal-integrity requirements.
The ATSAMD51J18A-AU-EFP SERCOM peripheral supports I2C Fast Mode Plus (1 MHz) only when the corresponding SERCOM pad supply is 3.3 V; at 1.8 V VDDIO, fall back to I2C Fast Mode (400 kHz). For SPI peripherals above 24 MHz, use the SERCOM in master mode with clock phase/control matched to the slave device timing. Add 33 ohm series damping resistors on long SPI traces (>50 mm) to suppress ringing without exceeding the GPIO drive-strength specification.
Do not enable the USB peripheral until VBUS has stabilized and the internal 48 MHz USB clock has settled, or the USB enumeration will fail intermittently. When using the I2S peripheral, configure the frame-sync and bit-clock pins to alternate SERCOM functions before enabling the peripheral to avoid glitches. The 12-bit ADC requires a minimum acquisition time of 200 ns per channel; shorter times cause crosstalk and inaccurate readings. Use FreeRTOS tick-less idle mode to take advantage of the integrated SleepWalking controller and reduce idle current to 5 uA.
Estimated: at maximum CPU activity (120 MHz with all peripherals active), the ATSAMD51J18A-AU-EFP dissipates approximately 60 mW from a 3.3 V supply. The 64-TQFP package has theta_JA of approximately 60 C/W (JEDEC EIA/JESD51 4-layer board), yielding a junction-to-ambient temperature rise of about 3.6 C. At the 85 C industrial ambient limit, the junction reaches 88.6 C, well below the 125 C maximum. No heatsink is required for typical IoT or industrial designs; ensure adequate ground-pour area for thermal spreading.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified; for automotive applications use ATSAM D5x automotive-grade variants. Halogen-free status not explicitly stated in provided web data.
