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ATSAMD21J18A-AFT

MCHPATSAMD21J18A-AFT

Microchip Technology
ARM® Cortex®-M0+ SAM D21J, Functional Safety (FuSa) Microcontroller IC 32-Bit 48MHz 256KB (256K x 8) FLASH 64-TQFP (10x10)
Active15,486 in stock
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Overview

The ATSAMD21J18A-AFT is a high-performance 32-bit ARM Cortex-M0+ microcontroller featuring 256KB of Flash and 32KB of SRAM. Operating at 48MHz, this device includes Functional Safety (FuSa) features and an extensive peripheral set including a Full-Speed USB interface.

Why Choose This Part

This MCU offers an excellent balance of low power consumption (1.62V to 3.63V range) and high integration, including 6 Sercom modules that can be individually configured as I2C, SPI, or UART. Its 12-channel DMA and 12-bit ADC allow for efficient data handling without taxing the CPU core.

Applications

Functional Safety Systems
Utilizes hardware features like the Watchdog Timer and Brown-out Detection to meet safety standards in industrial and consumer devices.
USB Connectivity Solutions
The integrated Full-speed USB 2.0 interface with embedded host and device capability makes it ideal for custom HID or CDC peripherals.
High-Pin Count Control
With 52 I/O pins and 20 ADC channels, it is suited for systems requiring high-density sensor interfacing and complex signal routing.
Prototyping and Education
As the core processor for several popular development boards, it benefits from extensive community libraries and open-source documentation.

Key Specifications

Speed 48MHz
RAM Size 32K x 8
Core Size 32-Bit
Peripherals Brown-out Detect/Reset, DMA, I2S, POR, PWM, WDT
Connectivity I2C, LINbus, SPI, UART/USART, USB
Mounting Type Surface Mount
Number of I/O 52
Core Processor ARM Cortex-M0+
Package / Case 64-TQFP
Data Converters A/D 20x12b; D/A 1x10b
Oscillator Type Internal
Program Memory Size 256KB (256K x 8)
Program Memory Type FLASH
Operating Temperature -40degC ~ 125degC (TA)
Supplier Device Package 64-TQFP (10x10)
Voltage - Supply (Vcc/Vdd) 1.62V ~ 3.6V

Getting Started

Development is primarily supported through Microchip Studio and the MPLAB X IDE, utilizing the XC32 compiler. For rapid prototyping, the SAM D21 Curiosity Nano or various Arduino-compatible boards provide an easy entry point with built-in debuggers and extensive software libraries.

Dev Boards

Development boards and breakout modules featuring the ATSAMD21J18A-AFT or compatible chips — ready to use for prototyping.

Seeed Studio XIAO SAMD21 Seeed Technology Co., Ltd
ATSAMD21G18 XIAO SAMD21 SAM D ARM® Cortex®-M0 MCU 32-Bit Embedded Evaluation Board
Digi-Key 509 in stock
Seeed Studio XIAO SAMD21 Seeed Technology Co., Ltd
ATSAMD21G18 XIAO SAMD21 SAM D ARM® Cortex®-M0+ MCU 32-Bit Embedded Evaluation Board
Digi-Key 4,149 in stock
Adafruit Feather M0 Express Adafruit Industries LLC
ATSAMD21G18 Feather M0 Express SAM D ARM® Cortex®-M0+ MCU 32-Bit Embedded Evaluation Board
Digi-Key Mouser 55 in stock
The Arduino Nano 33 IoT with Headers (ABX00032) is a compact and versatile development board featuring the ARM® Cortex®-
Digi-Key Mouser 783 in stock
The Arduino Nano 33 IoT (ABX00027) is an advanced evaluation platform designed for IoT applications, featuring the 32 bi
Digi-Key Mouser 800 in stock

ATSAMD21J Family

Part NumberDifferenceStock
ATSAMD21J17D-MZVAO 7D-MZVAO 240
ATSAMD21J17D-AZVAO 7D-AZVAO 295
ATSAMD21J16B-AZVAO 6B-AZVAO 319
ATSAMD21J18A-AZVAO ZVAO 286
ATSAMD21J18A-MUT QFN (tape) 13,544

Also Consider

ATSAMD21G18A-AUT MCHPMicrochip Technology - A more common 48-pin variant that offers the same memory and core specs but in a smaller footprint for space-constrained designs.
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