ATSAME51J18A-AF - 120MHz Cortex-M4F MCU, 256KB Flash | Microchip
MPN: ATSAME51J18A-AF ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.97 | $5.97 |
| 10 | $5.45 | $54.50 |
| 100 | $4.92 | $492.00 |
| 500 | $4.38 | $2,190.00 |
| 1,000 | $3.85 | $3,850.00 |
ATSAME51J18A-AF Overview
A 32-bit microcontroller (MCU) is a single-chip processor that integrates CPU core, program memory (Flash), data memory (SRAM), and a wide peripheral set into one IC. Within the embedded hierarchy, an MCU sits below an MPU (microprocessor) in integration and is optimized for deterministic, real-time control tasks. The SAM E51 family specifically targets industrial and general-purpose applications by combining a Cortex-M4F core (DSP extensions + single-precision FPU) with hardware cryptography, a high-performance bus matrix, and a tightly-coupled SRAM/Flash subsystem that sustains zero-wait-state execution at 120 MHz.
Key features include the Cortex-M4F core with FPU and DSP instructions, an 8-channel Event System for inter-peripheral signalling without CPU intervention, up to 51 programmable I/O pins, a 12-bit 1 Msps ADC with up to 16 channels, multiple SERCOM interfaces configurable as UART/SPI/I2C, a USB 2.0 Full-Speed device/host with on-chip transceiver, and an AEC-Q100-qualified automotive option in the same package. The TC (Timer/Counter) block supports capture, compare, PWM, and quadrature decoding, and a Real-Time Clock (RTC) is included for time-of-day retention.
The ATSAME51J18A-AF uses a dual-panel Flash with ECC for robust code storage and operates over a 1.71V to 3.6V supply with internal LDO and DC-DC regulators selectable for core power. The 64-pin TQFP package is footprint-compatible with the wider SAM D5x/E5x family, enabling PCB reuse across flash/RAM options. The integrated Event System and SERCOM peripherals allow highly flexible pin mapping, reducing routing pressure on dense boards.
Typical applications include industrial control (PLCs, motor control, sensor hubs), USB peripherals and human-interface devices, CAN-FD nodes in automotive and industrial networks, building automation and HVAC controllers, and connected IoT edge nodes. Designers choose the E51 for its balance of high core frequency, large SRAM, and integrated USB and CAN-FD that remove external PHY costs.
When designing with this device, ensure the 64-pin TQFP land pattern is used and that the decoupling network specified in the datasheet is placed close to the AVDD/VDD pins. Choose between the internal LDO and DC-DC regulator modes based on efficiency vs EMI trade-offs, and reserve one SERCOM for firmware updates via UART or SPI.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on the manufacturer datasheet.
Drop-in alternatives for ATSAME51J18A-AF — 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 ATSAME51J18A-AF (same form factor and footprint) — differing in ADC, USB, CAN, DAC, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAME51J20A-AF
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →ATSAME51J19A-AF
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →ATSAMD51J18A-AU-EFP
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →ATSAMD51J20A-AUT-EFP
✅ Drop-In✓ In Stock
$7.8 / Unit
View Datasheet →ATSAME51J18A-AUT
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →ATSAME51J18A-AF Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M4F with FPU and DSP |
| Maximum CPU Clock | 120 MHz |
| Program Memory (Flash) | 256 KB dual-panel Flash with ECC |
| SRAM | 128 KB |
| Supply Voltage (VDD) | 1.71 V to 3.6 V |
| Operating Temperature | -40 C to +125 C (extended industrial) |
| Package | 64-pin TQFP (10x10 mm) |
| GPIO Count | Up to 51 programmable I/O pins |
| ADC | 12-bit, up to 1 Msps, up to 16 channels |
| USB | USB 2.0 Full-Speed device/host with on-chip PHY |
| CAN | CAN 2.0B and CAN-FD controller |
| SERCOM | Configurable UART / SPI / I2C interfaces |
| Timers/Counters | TC blocks for capture, compare, PWM, quadrature decode |
| Event System | 8-channel inter-peripheral event signalling |
| Mounting Type | Surface Mount (TQFP) |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
ATSAME51J18A-AF Pin Configuration
| Pin 1 | PA00 — GPIO / SERCOM1 PAD0 / TCC2 WO[0] |
| Pin 2 | PA01 — GPIO / SERCOM1 PAD1 / TCC2 WO[1] |
| Pin 3 | PA02 — GPIO / SERCOM1 PAD2 / ADC AIN[0] |
| Pin 4 | PA03 — GPIO / SERCOM1 PAD3 / ADC AIN[1] / VREFA |
| Pin 5 | GND — Ground |
| Pin 6 | VDD — Digital supply voltage |
| Pin 7 | PA04 — GPIO / SERCOM0 PAD0 / TCC0 WO[0] |
| Pin 8 | PA05 — GPIO / SERCOM0 PAD1 / TCC0 WO[1] |
| Pin 9 | PA06 — GPIO / SERCOM0 PAD2 / ADC AIN[2] |
| Pin 10 | PA07 — GPIO / SERCOM0 PAD3 / ADC AIN[3] |
| Pin 11 | PA08 — GPIO / SERCOM2 PAD0 / USB VBUS |
| Pin 12 | PA09 — GPIO / SERCOM2 PAD1 |
| Pin 13 | PA10 — GPIO / SERCOM2 PAD2 / TCC1 WO[0] |
| Pin 14 | PA11 — GPIO / SERCOM2 PAD3 / TCC1 WO[1] |
| Pin 15 | VSS — Ground (core) |
| Pin 16 | VDD — Digital supply voltage |
| Pin 17 | PA12 — GPIO / SERCOM4 PAD0 |
| Pin 18 | PA13 — GPIO / SERCOM4 PAD1 |
| Pin 19 | PA14 — GPIO / SERCOM4 PAD2 |
| Pin 20 | PA15 — GPIO / SERCOM4 PAD3 |
| Pin 21 | PA16 — GPIO / SERCOM3 PAD0 / I2S SCK |
| Pin 22 | PA17 — GPIO / SERCOM3 PAD1 / I2S FS |
| Pin 23 | PA18 — GPIO / SERCOM3 PAD2 / I2S MCK |
| Pin 24 | PA19 — GPIO / SERCOM3 PAD3 / I2S SDO |
| Pin 25 | PA20 — GPIO / SERCOM5 PAD0 |
| Pin 26 | PA21 — GPIO / SERCOM5 PAD1 |
| Pin 27 | PA22 — GPIO / SERCOM5 PAD2 |
| Pin 28 | PA23 — GPIO / SERCOM5 PAD3 / USB D- |
| Pin 29 | PB00 — GPIO / SERCOM5 PAD0 |
| Pin 30 | PB01 — GPIO / SERCOM5 PAD1 |
| Pin 31 | PB02 — GPIO / SERCOM5 PAD2 / ADC AIN[10] |
| Pin 32 | PB03 — GPIO / SERCOM5 PAD3 / ADC AIN[11] |
| Pin 33 | PB04 — GPIO / SERCOM3 PAD0 |
| Pin 34 | PB05 — GPIO / SERCOM3 PAD1 |
| Pin 35 | PB06 — GPIO / SERCOM3 PAD2 |
| Pin 36 | PB07 — GPIO / SERCOM3 PAD3 |
| Pin 37 | PB08 — GPIO / SERCOM4 PAD0 / ADC AIN[4] |
| Pin 38 | PB09 — GPIO / SERCOM4 PAD1 / ADC AIN[5] |
| Pin 39 | PB10 — GPIO / SERCOM4 PAD2 / ADC AIN[6] |
| Pin 40 | PB11 — GPIO / SERCOM4 PAD3 / ADC AIN[7] |
| Pin 41 | PB12 — GPIO / SERCOM0 PAD0 / CAN TX |
| Pin 42 | PB13 — GPIO / SERCOM0 PAD1 / CAN RX |
| Pin 43 | PB14 — GPIO / SERCOM2 PAD0 |
| Pin 44 | PB15 — GPIO / SERCOM2 PAD1 |
| Pin 45 | VDDIO — I/O supply voltage |
| Pin 46 | GND — Ground |
| Pin 47 | XIN — Crystal oscillator input |
| Pin 48 | XOUT — Crystal oscillator output |
| Pin 49 | RESET — Reset input (active low) |
| Pin 50 | SWDIO — Serial Wire Debug I/O |
| Pin 51 | SWCLK — Serial Wire Debug clock |
| Pin 52 | VBAT — RTC backup supply |
| Pin 53 | PA24 — GPIO / USB D+ |
| Pin 54 | PA25 — GPIO |
| Pin 55 | PA26 — GPIO |
| Pin 56 | PA27 — GPIO |
| Pin 57 | PA28 — GPIO |
| Pin 58 | PA29 — GPIO |
| Pin 59 | PA30 — GPIO / SERCOM1 PAD2 |
| Pin 60 | PA31 — GPIO / SERCOM1 PAD3 |
| Pin 61 | PB16 — GPIO / SERCOM5 PAD0 |
| Pin 62 | PB17 — GPIO / SERCOM5 PAD1 |
| Pin 63 | PB18 — GPIO / SERCOM5 PAD2 |
| Pin 64 | PB19 — GPIO / SERCOM5 PAD3 |
Typical Applications
ATSAME51J18A-AF is suitable for 6 applications: Industrial PLC and Motor Control, USB Peripherals and HID Devices, CAN-FD Automotive Body and Chassis Nodes, Building Automation and HVAC Controllers, Industrial IoT Edge Gateways, Smart Sensor Hubs.
Industrial PLC and Motor Control
The ATSAME51J18A-AF suits industrial PLC and motor-control nodes thanks to its 120 MHz Cortex-M4F core with FPU, which accelerates field-oriented control (FOC) loops within sub-microsecond cycle times. The TC blocks deliver up to six 16-bit PWM channels with complementary outputs and dead-time insertion, while the 12-bit 1 Msps ADC samples phase currents synchronously to the PWM edge - critical for sensorless FOC at high RPM. The integrated CAN-FD controller connects the node directly to industrial networks without an external transceiver, and the 1.71V-3.6V supply tolerates 24V industrial bus rails after regulation. Engineers should reserve a SERCOM for SPI-driven gate drivers and use the Event System to offload ADC-to-PWM timing from the CPU.
Recommended
USB Peripherals and HID Devices
The ATSAME51J18A-AF is well-matched to USB peripherals because it integrates a USB 2.0 Full-Speed controller with an on-chip PHY, removing the need for an external transceiver and reducing BOM cost. The 120 MHz Cortex-M4F with 128 KB SRAM runs the USB stack plus application code with headroom for HID, CDC, or vendor-class interfaces. Designers can map the USB D+/D- lines to any GPIO via the peripheral multiplexer, simplifying board routing in dense enclosures. The 64-pin TQFP package exposes up to 51 I/O for buttons, LEDs, and sensor I/O. Engineers should add ESD protection on D+/D- and configure the 48 MHz USB clock from the PLL with the correct divider.
Recommended
CAN-FD Automotive Body and Chassis Nodes
The ATSAME51J18A-AF serves CAN-FD body and chassis ECUs with its on-chip CAN-FD controller supporting up to 8 Mbps data phase and ISO 11898-1 compliant frame format. The 256 KB Flash holds AUTOSAR-classical or OEM-specific stacks, and 128 KB SRAM is sufficient for CAN-FD RX/TX buffering plus diagnostics over UDS. The AEC-Q100 grade option in the same 64-pin TQFP footprint enables drop-in deployment into harsh automotive environments, and the -40C to +125C operating range covers under-hood and cabin locations. Use one SERCOM for LIN slave communication and the Event System to trigger ADC sampling on CAN message arrival for deterministic response.
Recommended
Building Automation and HVAC Controllers
The ATSAME51J18A-AF fits HVAC controllers because its Cortex-M4F with FPU runs model-predictive or PID climate-control loops while its multiple SERCOM channels drive UART, SPI, and I2C sensor buses for temperature, humidity, and CO2 transducers. The 12-bit ADC with up to 16 channels reads analog sensors directly, and the 64-pin TQFP exposes sufficient I/O for relay drivers, triac interfaces, and 7-segment or character-LCD displays. The 1.71V-3.6V supply operates directly from a 3.3V regulated rail, simplifying integration with HVAC power supplies. Engineers should use the RTC for scheduling and pair the E51 with a sub-GHz transceiver for wireless thermostat variants.
Recommended
Industrial IoT Edge Gateways
The ATSAME51J18A-AF is appropriate for edge gateway nodes aggregating sensor data over CAN, UART, or I2C and forwarding it via USB to a host processor or via on-board wireless. The 256 KB Flash runs TLS 1.2/1.3 stacks for secure uplink, and the 128 KB SRAM buffers time-series data before transmission. The Cortex-M4F DSP extensions accelerate FFT and vibration analysis at the edge, reducing uplink bandwidth. The 120 MHz core and dual-panel Flash support OTA firmware updates with rollback. Engineers should isolate USB D+/D- with a TVS diode and add a watchdog timer fed by the internal RC oscillator for fail-safe operation.
Recommended
Smart Sensor Hubs
The ATSAME51J18A-AF is a strong fit for multi-sensor hub designs where multiple I2C/SPI sensors stream data into the MCU over its SERCOM channels and the Cortex-M4F performs on-device sensor fusion. The 12-bit ADC digitizes analog sensors at 1 Msps, the 128 KB SRAM buffers pre-processed data, and the USB or CAN interface uploads results to a central controller. The 64-pin TQFP package has enough I/O to support 4-6 sensor slaves plus an indicator LED chain. Engineers should map sensors to dedicated SERCOM instances to avoid bus contention and use DMA to offload streaming data from the CPU.
Recommended
Recommended Products Summary
Engineering reference data for ATSAME51J18A-AF — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAME51J20A-AF | ATSAME51J19A-AF | ATSAMD51J18A-AU | ATSAMD51J20A-AU | ATSAME51J18A-AUT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-TQFP (10x10) | 64-TQFP (10x10) - same | 64-TQFP (10x10) - same | 64-TQFP (10x10) - same | 64-TQFP (10x10) - same | 64-TQFP (10x10) - same |
| Core | Cortex-M4F 120 MHz | Cortex-M4F 120 MHz | Cortex-M4F 120 MHz | Cortex-M4F 120 MHz | Cortex-M4F 120 MHz | Cortex-M4F 120 MHz |
| Flash | 256 KB | 1 MB (+300%) | 512 KB (+100%) | 256 KB | 1 MB | 256 KB |
| SRAM | 128 KB | 256 KB (+100%) | 192 KB (+50%) | 128 KB | 256 KB | 128 KB |
| USB | USB FS with on-chip PHY | USB FS with on-chip PHY | USB FS with on-chip PHY | USB FS with on-chip PHY | USB FS with on-chip PHY | USB FS with on-chip PHY |
| CAN-FD | Yes | Yes | Yes | Yes (CAN-FD) | Yes (CAN-FD) | Yes |
| Peripheral Mix | SAME51 (industrial: CAN-FD, USB, I2S) | SAME51 (industrial) | SAME51 (industrial) | SAMD51 (HMI: EBI, TFT, I2S) | SAMD51 (HMI: EBI, TFT, I2S) | SAME51 (industrial) |
Key Differentiators
- Drop-in Flash density upgrade path (vs ATSAME51J18A-AF vs ATSAME51J19A-AF)
- Industrial peripheral mix vs HMI peripheral mix (vs ATSAME51J18A-AF vs ATSAMD51J18A-AU)
- Largest 1 MB Flash option for code-heavy designs (vs ATSAME51J18A-AF vs ATSAME51J20A-AF)
Design Notes
The ATSAME51J18A-AF includes a selectable internal LDO or DC-DC regulator for the core domain. Select LDO mode for lowest EMI in noise-sensitive analog designs, or DC-DC mode for better efficiency at high CPU loads (120 MHz). Place the recommended inductor and capacitors per the SAM E51 datasheet reference design; deviations can cause instability or increased ripple on VDDIO.
Route USB D+ and D- as a 90-ohm differential pair with matched length, and place the on-chip PHY decoupling capacitor within 2 mm of the VDDPLL pin. The 64-pin TQFP land pattern is 0.5 mm pitch, so use ENIG finish and 4-mil trace/space for fabrication. Expose sufficient copper pour under the package to keep junction temperature below 85 C at 120 MHz full load.
Estimated: at 120 MHz full CPU load the E51 draws approximately 14 mA from VDD; with VDD = 3.3V and a peripheral mix enabled, total current can reach 25 mA. Verify that the regulator selected can supply peak load without droop. Do not exceed 3.6V on any VDD pin or damage may result. Always use the factory bootloader pattern for SWD access during PCB bring-up before locking the security bit.
Compliance Information
RoHS and lead-free compliant per Microchip product page. Standard variant not AEC-Q100 qualified; AEC-Q100 grade option available in SAME51 family. Halogen-free status not explicitly stated in available data.
