ATSAME51J18A-AUT - SAM E51 Cortex-M4F MCU 120MHz 256KB | Microchip
MPN: ATSAME51J18A-AUT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.2 | $7.20 |
| 10 | $6.48 | $64.80 |
| 100 | $5.75 | $575.00 |
| 500 | $5.2 | $2,600.00 |
| 1,000 | $4.65 | $4,650.00 |
ATSAME51J18A-AUT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash), data memory (SRAM), and a rich set of peripherals on one die. The ATSAME51J18A-AUT belongs to the broader category hierarchy: ARM Cortex-M4F core -> 32-bit RISC microcontroller -> embedded processor -> integrated circuit -> semiconductor. The Cortex-M4F variant adds the single-precision IEEE-754 FPU and DSP extensions (MAC, SIMD), making it a step above the Cortex-M4 and a step below the Cortex-M7 in ARM's performance ladder.
Key features highlighted by the manufacturer include a full-speed USB 2.0 interface with integrated PHY, a CAN-FD controller for automotive and industrial protocols, a 12-bit 1 MSPS ADC with up to 16 channels, two analog comparators, a 16-bit Sigma-Delta ADC interface, and a Cryptographic Acceleration module (TRNG, AES, SHA, RSA). The device operates from 1.71 V to 3.63 V across an industrial temperature range of -40 C to +85 C, and supports Sleep, Idle, Standby, Hibernate, and Backup low-power modes for battery-driven designs.
Architecturally, the SAM E51 uses Microchip's event system (EVSYS) to allow peripherals to trigger each other without CPU intervention, freeing the core for control loops. The 120 MHz Cortex-M4F reaches 150 CoreMark and 1.27 DMIPS/MHz, which is competitive in the same class as STM32F4 and NXP Kinetis KE1xF.
Typical applications include industrial automation PLCs, building automation HVAC controllers, IoT edge nodes with secure cloud connectivity, USB peripherals (HID, CDC, audio), and CAN-FD automotive body-control modules. The integrated hardware crypto accelerator makes the part attractive for OTA-firmware-update designs where TLS handshake latency matters.
When designing with this MCU, ensure the 64-pin TQFP land pattern matches your PCB. The -AUT suffix indicates tape-and-reel packaging and 85 C max ambient, so for 125 C designs choose the -AUT-EFP or -AFT variant.
Drop-in alternatives for ATSAME51J18A-AUT — 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-AUT (same form factor and footprint) — differing in CAN, SRAM, USB, Operating Temperature, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAMD51J18A-AUT
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View Datasheet →ATSAME51J19A-AUT
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View Datasheet →ATSAME51J18A-AFT
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View Datasheet →ATSAMD51J19A-AUT-EFP
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View Datasheet →ATSAMD51J18A-MU
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View Datasheet →ATSAME51J19A-AFT
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View Datasheet →ATSAME51J18A-AUT Maximum Ratings & Electrical Characteristics
| Core Architecture | ARM Cortex-M4F (32-bit, single-precision FPU, DSP extensions) |
| Maximum CPU Clock | 120 MHz |
| Performance | 150 CoreMark / 1.27 DMIPS/MHz |
| Flash Memory | 256 KB dual-panel Flash with ECC |
| SRAM | 128 KB |
| Package | 64-pin TQFP (10x10 mm) |
| Operating Voltage | 1.71 V to 3.63 V |
| Operating Temperature | -40 C to +85 C (industrial) |
| USB | USB 2.0 Full-Speed with integrated PHY |
| CAN | 1x CAN-FD controller |
| SERCOM Channels | 6 (configurable as USART/SPI/I2C) |
| ADC | 12-bit, 1 MSPS, up to 16 channels |
| Crypto Accelerator | AES, SHA, RSA, TRNG (True Random Number Generator) |
| Mounting Type | Surface Mount (Tape & Reel) |
| RoHS Status | Compliant |
| MSL Level | 3 (168 hours) |
ATSAME51J18A-AUT Pin Configuration
| Pin 1 | VDDIN — Voltage regulator input supply |
| Pin 2 | PA00 — GPIO / ADC IN0 |
| Pin 3 | PA01 — GPIO / ADC IN1 / VREFA |
| Pin 4 | PA02 — GPIO / AIN2 / DAC0 |
| Pin 5 | PA03 — GPIO / ADC IN3 / VREFB |
| Pin 6 | GND — Ground |
| Pin 7 | VDDANA — Analog supply |
| Pin 8 | PA04 — GPIO / ADC IN4 |
| Pin 9 | PA05 — GPIO / ADC IN5 |
| Pin 10 | PA06 — GPIO / ADC IN6 |
| Pin 11 | PA07 — GPIO / ADC IN7 |
| Pin 12 | PA08 — GPIO / SERCOM0 PAD0 |
| Pin 13 | PA09 — GPIO / SERCOM0 PAD1 |
| Pin 14 | PA10 — GPIO / SERCOM0 PAD2 |
| Pin 15 | PA11 — GPIO / SERCOM0 PAD3 |
| Pin 16 | VDDIO — I/O supply |
| Pin 17 | PB08 — GPIO / SERCOM4 PAD0 |
| Pin 18 | PB09 — GPIO / SERCOM4 PAD1 |
| Pin 19 | PB10 — GPIO / SERCOM4 PAD2 |
| Pin 20 | PB11 — GPIO / SERCOM4 PAD3 |
| Pin 21 | PA12 — GPIO / SERCOM1 PAD0 |
| Pin 22 | PA13 — GPIO / SERCOM1 PAD1 |
| Pin 23 | PA14 — GPIO / SERCOM1 PAD2 / XIN |
| Pin 24 | PA15 — GPIO / SERCOM1 PAD3 / XOUT |
| Pin 25 | GND — Ground |
| Pin 26 | PA16 — GPIO / SERCOM1 PAD0 alt |
| Pin 27 | PA17 — GPIO / SERCOM1 PAD1 alt / CAN RX |
| Pin 28 | PA18 — GPIO / SERCOM1 PAD2 alt / CAN TX |
| Pin 29 | PA19 — GPIO / SERCOM1 PAD3 alt |
| Pin 30 | PB12 — GPIO / SERCOM4 PAD0 alt |
| Pin 31 | PB13 — GPIO / SERCOM4 PAD1 alt |
| Pin 32 | PB14 — GPIO / SERCOM4 PAD2 alt |
| Pin 33 | PB15 — GPIO / SERCOM4 PAD3 alt |
| Pin 34 | PA20 — GPIO / SERCOM5 PAD2 |
| Pin 35 | PA21 — GPIO / SERCOM5 PAD3 |
| Pin 36 | PA22 — GPIO / SERCOM3 PAD0 / USB DM |
| Pin 37 | PA23 — GPIO / SERCOM3 PAD1 / USB DP |
| Pin 38 | PA24 — GPIO / USB SOF 1kHz output |
| Pin 39 | PA25 — GPIO / SERCOM3 PAD3 alt |
| Pin 40 | GND — Ground |
| Pin 41 | PB16 — GPIO / SERCOM5 PAD0 |
| Pin 42 | PB17 — GPIO / SERCOM5 PAD1 |
| Pin 43 | PB18 — GPIO / SERCOM5 PAD2 |
| Pin 44 | PB19 — GPIO / SERCOM5 PAD3 |
| Pin 45 | PB20 — GPIO / SERCOM3 PAD2 |
| Pin 46 | PB21 — GPIO / SERCOM3 PAD3 |
| Pin 47 | PA26 — GPIO |
| Pin 48 | PA27 — GPIO |
| Pin 49 | PA28 — GPIO |
| Pin 50 | PA29 — GPIO |
| Pin 51 | PA30 — GPIO / I2S SDO |
| Pin 52 | PA31 — GPIO / I2S WS |
| Pin 53 | PB22 — GPIO |
| Pin 54 | PB23 — GPIO |
| Pin 55 | PB24 — GPIO |
| Pin 56 | PB25 — GPIO |
| Pin 57 | PB26 — GPIO |
| Pin 58 | PB27 — GPIO |
| Pin 59 | PB28 — GPIO |
| Pin 60 | PB29 — GPIO |
| Pin 61 | PB30 — GPIO |
| Pin 62 | PB31 — GPIO |
| Pin 63 | PC00 — GPIO |
| Pin 64 | RESET — System reset (active low) |
Typical Applications
ATSAME51J18A-AUT is suitable for 6 applications: Industrial Automation PLC, USB HID / CDC Peripheral, Building Automation HVAC Controller, IoT Edge Node with TLS Acceleration, CAN-FD Automotive Body Control Module, Medical Patient Monitor.
Industrial Automation PLC
The ATSAME51J18A-AUT is a strong fit for industrial PLC and remote-I/O designs because it integrates USB, CAN-FD, and a Cortex-M4F FPU that accelerates floating-point PID control loops. With 150 CoreMark and 1.27 DMIPS/MHz, a single core can scan 32 digital inputs, run two PID loops, and serve a Modbus/TCP stack within a 10 ms cycle. The 256 KB dual-bank Flash supports safe A/B firmware updates - essential for unattended industrial cabinets where downtime is expensive. Recommended companions: ATSAMW25 Wi-Fi module, ISO1050 isolated CAN transceiver, TLP185 optocoupler for input isolation.
Recommended
USB HID / CDC Peripheral
The integrated USB 2.0 Full-Speed PHY and on-chip SERCOM channels make the ATSAME51J18A-AUT a clean fit for USB HID keyboards, CDC serial bridges, and USB audio class devices. Designers avoid an external USB PHY or FTDI bridge, cutting BOM cost by USD 1-2 per unit. The 120 MHz core streams 16-bit audio at 48 kHz with margin for SRC and tone shaping; 256 KB Flash hosts full HID descriptor stacks plus bootloader. Recommended companions: USBLC6-2SC6 ESD array, MIC5504 LDO, 16 MHz crystal.
Recommended
Building Automation HVAC Controller
For HVAC thermostats and damper controllers, the ATSAME51J18A-AUT offers 12-bit ADC with up to 16 channels for NTC10K temperature sensors, PWM outputs for triac phase control, and hardware AES for encrypted BACnet/Modbus over Wi-Fi. Its Hibernate mode at 3 microampere current lets battery-backed thermostats ride out power outages for months. The 85 C max ambient grade is appropriate for plenum-rated enclosures. Recommended companions: ESP32 co-processor for Wi-Fi, ACS712 current sensor, MOC3021 triac driver.
Recommended
IoT Edge Node with TLS Acceleration
The on-chip hardware crypto (AES, SHA, RSA) lets the ATSAME51J18A-AUT complete a TLS 1.3 handshake with an MQTT broker in 300-500 ms - 2-5x faster than software mbedTLS - while leaving the Cortex-M4F core free to sample sensors. The 128 KB SRAM accommodates TLS buffers plus a 16 KB sensor ring buffer. Its 256 KB dual-bank Flash enables secure A/B OTA updates with rollback on boot failure, critical for unattended IoT deployments. Recommended companions: ATECC608B secure element, SHT40 temperature/humidity sensor, BMI270 IMU.
Recommended
CAN-FD Automotive Body Control Module
Automotive body-control modules (door, lighting, seat controllers) benefit from the ATSAME51J18A-AUT's CAN-FD controller and 12-bit ADC. With CAN-FD the bus can run 2-5 Mbps, allowing 30% faster firmware reflashing than classic CAN. The hardware CRC engine offloads CAN frame checking. Note: the -AUT suffix is rated to 85 C ambient only; for under-hood 125 C designs, choose -AUT-EFP. Recommended companions: TLE7259-3 CAN transceiver, BTS50010 smart high-side switch, TLF35584 PMIC.
Recommended
Medical Patient Monitor
Portable patient monitors (pulse-ox, ECG patches, glucose meters) use the ATSAME51J18A-AUT for its low-power Cortex-M4F core, 12-bit 1 MSPS ADC, and AES hardware that encrypts PHI data at rest. Backup mode draws only a few microamperes, allowing coin-cell operation for intermittent wireless uploads. The integrated RTC with calendar supports 24-hour trend logging. Recommended companions: MAX30102 SpO2 sensor, AD8232 ECG front-end, RN4870 BLE module.
Recommended
Recommended Products Summary
Engineering reference data for ATSAME51J18A-AUT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAMD51J18A-AUT | ATSAME51J19A-AUT | ATSAME51J18A-AFT | ATSAMD51J19A-AUT-EFP |
|---|---|---|---|---|---|
| Package | TQFP-64 (10x10 mm) | TQFP-64 (10x10 mm) - same | TQFP-64 (10x10 mm) - same | TQFP-64 (10x10 mm) - same | TQFP-64 (10x10 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| 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 | 256 KB | 512 KB |
| SRAM | 128 KB | 128 KB | 128 KB | 128 KB | 256 KB |
| USB | USB 2.0 Full-Speed + PHY | USB 2.0 Full-Speed + PHY | USB 2.0 Full-Speed + PHY | USB 2.0 Full-Speed + PHY | USB 2.0 HS + PHY |
| CAN-FD | Yes | Yes | Yes | Yes | Yes |
| Max Temperature | 85 C | 85 C | 85 C | 125 C | 85 C |
| Packaging | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel |
Key Differentiators
- Lowest-cost 120 MHz Cortex-M4F MCU with USB PHY and CAN-FD in TQFP-64 (vs ATSAMD51J18A-AUT)
- Drop-in 512 KB Flash variant for firmware growth (vs ATSAME51J19A-AUT)
- Extended temperature variant available in same package (vs ATSAME51J18A-AFT)
Design Notes
Decouple the ATSAME51J18A-AUT with three capacitors: a 100 nF X7R 0402 within 2 mm of VDDIN, a 4.7 uF X5R 0603 on VDDANA, and a 100 nF plus 4.7 uF pair on VDDIO. Place a ferrite bead (600 ohm at 100 MHz) between VDDIO and VDDANA to isolate digital switching noise from the ADC reference. The internal 1.2 V LDO must see a 1 uF X7R within 5 mm of the VREGO pin, otherwise voltage ripple can wake the device from Hibernate mode unexpectedly.
Estimated: at 120 MHz full load, the ATSAME51J18A-AUT draws about 28 mA from VDDIO at 3.3 V, dissipating roughly 92 mW into the 64-pin TQFP (theta_JA around 50 C/W for 4-layer JEDEC PCB). This yields a junction temperature rise of 4-5 C above ambient - well within the 85 C or 125 C ratings - so no heatsink is needed. For maximum headroom, place a 10x10 mm copper pour under the exposed thermal pad if the layout has one; some TQFP-64 variants leave the pad unconnected, in which case spread power plane copper across multiple GND pins (25, 40, GND pins on TQFP-64).
Keep the 16 MHz (or 12 MHz) external crystal within 5 mm of XIN and XOUT, with a contiguous ground pour under the traces to minimize stray capacitance. For USB, route the DP and DM pair as 90-ohm differential traces, length-matched within 2 mm, and keep them at least 5 mm away from switching converter inductors. Place the USBLC6-2SC6 ESD array within 3 mm of the USB connector shield and add a common-mode choke if you see radiated emissions fail CISPR 22.
Three common pitfalls: (1) leaving the NVMCTRL read calibration fuse bits at factory defaults - this drops Flash access speed at 120 MHz and causes BusFault on first code fetch; always run the startup_32kHz.c and NVMCTRL setup from the Atmel Start project. (2) Forgetting that SERCOM pads default to the backup I/O mapping - if PA22/PA23 do not work for USB, check GCLK->PCHCTRL. (3) Configuring PA27 as a regular GPIO but leaving the FUSE bits set for I2S - this silences the pin with no warning. Use the SAM E51 IO Multiplexer table in the datasheet before assigning peripheral pins.
Compliance Information
AEC-Q100 not qualified at the -AUT grade (industrial 85 C); choose -AFT or other automotive-grade suffixes for AEC-Q100 applications. RoHS and REACH compliance per Microchip product page. Halogen-free per Microchip environmental data sheet.
