Parts SAM Microcontrollers Family SAMD21G ATSAMD21G18

MCHPATSAMD21G18

Name: ATSAMD21G18
Brand: Microchip Technology

Microchip Technology

32-bit Cortex-M0+ with native USB and more RAM/flash for more complex USB-capable projects.

Obsolete2,131 in stock

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Overview

The Microchip ATSAMD21G18 is a 32-bit ARM Cortex-M0+ microcontroller running up to 48 MHz with 256 KB of flash and 32 KB of RAM. It provides native USB, about 38 GPIOs, and a broad peripheral set including I2C, SPI, UART/USART, DMA, PWM, I2S, WDT and brown-out/por support. The device operates from 1.62 V to 3.6 V making it suitable for typical 3.3 V embedded designs.

Why Choose This Part

Native USB plus 256 KB flash and 32 KB RAM give enough headroom for USB stacks, file systems and higher-level firmware without external memory. The Cortex-M0+ core is power-efficient and the device has a flexible peripheral set (SERCOM-like multi-protocol serials, DMA, PWM, I2S) that covers most embedded connectivity needs. Strong community and board support (Arduino cores, third-party breakouts) speed development and debugging.

Applications

USB peripherals and gadgets

Implement USB HID, CDC (serial), MIDI or mass-storage devices using the on-chip native USB interface and available stacks.

Sensor hubs and data loggers

Collect and pre-process sensor data using multiple serial interfaces (I2C, SPI, UART) and DMA to reduce CPU load.

Prototyping and education

Popular on hobbyist/dev boards (Arduino Zero, Feather M0) for rapid prototyping, USB connectivity and easy toolchain support.

Low-to-moderate performance embedded control

Suitable for motor controllers, user-interface controllers and general-purpose embedded systems that need modest CPU performance and real-time peripherals.

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 38

Core Processor ARM Cortex-M0+

Package / Case 48-VFQFN Exposed Pad

Data Converters A/D 14x12b; D/A 1x10b

Oscillator Type Internal

Program Memory Size 256KB (256K x 8)

Program Memory Type FLASH

Operating Temperature -40degC ~ 85degC (TA)

Supplier Device Package 48-QFN (7x7)

Voltage - Supply (Vcc/Vdd) 1.62V ~ 3.6V

Getting Started

Common development boards: Arduino Zero, Adafruit Feather M0, SparkFun SAMD21 breakouts and many generic SAMD21 boards. Toolchains: Arduino IDE with the SAMD core for quick sketches, or ARM GCC-based toolchains and Microchip/Atmel Studio for production development; debuggers such as CMSIS-DAP or Atmel-ICE are supported. Practical tips: design for a 3.3 V domain, provide a reliable 48 MHz USB clock source or configuration, and use available example USB stacks and board support packages to accelerate bring-up.

Dev Boards

Development boards and breakout modules featuring the ATSAMD21G18 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 3,141 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 364 in stock

Arduino Nano 33 IoT Arduino

The Arduino Nano 33 IoT with Headers (ABX00032) is a compact and versatile development board featuring the ARM® Cortex®-

Digi-Key Mouser 355 in stock

Arduino Nano 33 IoT Arduino

The Arduino Nano 33 IoT (ABX00027) is an advanced evaluation platform designed for IoT applications, featuring the 32 bi

Digi-Key Mouser 657 in stock

Part of SAM Microcontrollers family » SAMD21G

SAMD21G Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number	Package	Temp Range	Stock
ATSAMD21G18 (this part)	VFQFN-48	-40degC ~ 85degC (..	2,131
ATSAMD21G18A-AU	TQFP-48	-40degC ~ 85degC (..	3,277
ATSAMD21G18A-AUT	TQFP-48	-40degC ~ 85degC (..	4,963
ATSAMD21G18A-AFT	TQFP-48	-40degC ~ 125degC ..	20,008
ATSAMD21G18A-MUT	VFQFN-48	-40degC ~ 85degC (..	3,079
ATSAMD21G18A-MFT	VFQFN-48	-40degC ~ 125degC ..	7,004
ATSAMD21G18A-AF	TQFP-48	-40degC ~ 125degC ..	1,491

Also available as: ATSAMD21G18A-MZVAO, ATSAMD21G16B-AZVAO, ATSAMD21G17D-AZVAO, ATSAMD21G18A-MF

Also Consider

ATSAMD21G18A-MU MCHPMicrochip Technology - Pin-compatible/variant with the same core and resources, common alternative package option.

ATSAMD51J19A-MU MCHPMicrochip Technology - Higher-performance Cortex-M4F sibling in the SAMD family for more CPU and DSP horsepower while keeping comparable peripherals.

STM32F103C8T6

STMicroelectronics - Widely used Cortex-M3 alternative with USB-capable variants and strong ecosystem for similar embedded USB and prototyping projects.