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ATSAMD21G18A-AU

MCHPATSAMD21G18A-AU

Microchip Technology
ARM® Cortex®-M0+ SAM D21G, Functional Safety (FuSa) Microcontroller IC 32-Bit 48MHz 256KB (256K x 8) FLASH 48-TQFP (7x7)
Active5,749 in stock
Datasheet Digi-Key Compare Prices

Overview

The ATSAMD21G18A-AU is a 32-bit microcontroller based on the ARM Cortex-M0+ core running up to 48 MHz, with 256 KB of flash and 32 KB of SRAM. It is a functional-safety (FuSa) variant in a 48-pin TQFP (7x7) package and supports a wide supply range (1.62 V to 3.6 V). The device includes common peripherals such as USB, I2C, SPI, UART, DMA, PWM, I2S and LIN bus support, making it suitable for embedded control and safety-aware applications.

Why Choose This Part

The SAMD21G18A balances moderate CPU performance with ample flash (256 KB) and SRAM (32 KB) for embedded applications while exposing a rich peripheral set (USB, LIN, I2S, DMA, PWM) that reduces external component count. Its FuSa-designated variant and wide supply voltage range make it a practical choice for designs that need enhanced safety diagnostics and operation across 1.62 V to 3.6 V systems. The 48-pin TQFP package is hobbyist- and assembly-friendly, easing prototyping and small-volume production.

Applications

Safety-certified embedded controllers
Use in systems that require functional-safety features and diagnostics for controlled shutdown and fault handling.
Automotive body and convenience modules
Suitable for LIN-connected vehicle nodes, sensor aggregation, and low-speed vehicle networking functions.
USB peripheral devices
Implement USB device or USB-enabled endpoints such as USB HID, CDC (virtual COM), or simple USB audio interfaces.
Arduino-compatible prototyping and maker projects
Used on popular Arduino Zero and compatible boards for rapid development with Arduino libraries and shields.
Industrial and building automation
Control panels, sensor hubs, and PWM-based actuator control where deterministic MCU behavior and safety features are beneficial.

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-TQFP
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-TQFP (7x7)
Voltage - Supply (Vcc/Vdd) 1.62V ~ 3.6V

Getting Started

Get started using off-the-shelf development boards such as Arduino Zero or Adafruit M0-series (Feather/Metro) that use SAMD21G18A variants. For toolchains, use the Arduino IDE for quick prototyping, or use arm-none-eabi GCC with a CMSIS/Atmel START or Microchip software framework for production firmware. Debug and program via SWD using tools like Atmel-ICE, SEGGER J-Link, or OpenOCD-compatible adapters.

Dev Boards

Development boards and breakout modules featuring the ATSAMD21G18A-AU 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 (ABX00027) is an advanced evaluation platform designed for IoT applications, featuring the 32 bi
Digi-Key Mouser 800 in stock
ATSAMD21G18A Microchip Technology
ARM Cortex-M0+ MCU with strong Arduino and low-power application support, useful for single-core embedded designs.
Digi-Key Mouser 2,131 in stock

ATSAMD21G Family

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

Part Number Package Temp Range Stock
ATSAMD21G18A-AU (this part) TQFP-48 -40degC ~ 85degC (.. 5,749
ATSAMD21G18A-MU VFQFN-48 -40degC ~ 85degC (.. 1,624
ATSAMD21G18A-AUT TQFP-48 -40degC ~ 85degC (.. 922
ATSAMD21G18A-AFT TQFP-48 -40degC ~ 125degC .. 26,221
ATSAMD21G18A-MUT VFQFN-48 -40degC ~ 85degC (.. 4,133
ATSAMD21G18A-AF TQFP-48 -40degC ~ 125degC .. 1,697
ATSAMD21G18A-MFT VFQFN-48 -40degC ~ 125degC .. 11,740
Also available as: ATSAMD21G18A-MZVAO, ATSAMD21G18A-MF, ATSAMD21G16B-AZVAO, ATSAMD21G17D-AZVAO

Also Consider

ATSAMD21G18A-MU MCHPMicrochip Technology - Same SAM D21G18A silicon in a different (MU) package option for board-level footprint differences.
ATSAMD51J19A-AU MCHPMicrochip Technology - Higher-performance SAM D5x family member if you need a faster Cortex-M4F upgrade with more memory and peripherals.
STM32F103C8T6 STMicroelectronics - Popular low-cost ARM Cortex-M3 alternative with different performance and peripheral tradeoffs for similar embedded tasks.

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Categories

Industrial & Automation > Functional Safety
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