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SAMR21G18A

MCHPSAMR21G18A

Microchip Technology
ARM Cortex-M0+ SoC with integrated 802.15.4 radio and a more modern MCU core for larger ecosystem support.
Active9,186 in stock
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Overview

The SAMR21G18A is a wireless microcontroller that combines an ARM Cortex-M0+ MCU with an integrated 2.4GHz IEEE 802.15.4 compliant radio. It provides 256kB of Flash and 32kB of SRAM, designed for low-power mesh networking applications using Zigbee, Thread, or 6LoWPAN protocols.

Why Choose This Part

This SoC integrates a high-performance 48MHz MCU with specialized wireless features like antenna diversity and hardware-assisted MAC functions (Auto-Retry and Auto-Acknowledge). The SleepWalking peripherals and low-power standby modes minimize energy consumption during radio inactivity.

Applications

Zigbee Home Automation
Ideal for smart light switches, thermostats, and sensors requiring reliable mesh networking and long battery life.
Industrial Sensor Networks
Utilizes the 802.15.4 MAC hardware support and -99dBm sensitivity for robust data collection in harsh RF environments.
Thread Networking
Supports IP-based mesh networking for modern smart home ecosystems using the Cortex-M0+ core and dedicated radio frame buffers.

Key Specifications

GPIO 28
Type TxRx + MCU
Frequency 2.4GHz
Modulation O-QPSK
Memory Size 256kB Flash, 32kB SRAM
Sensitivity -99dBm
Mounting Type Surface Mount
Package / Case 48-VFQFN Exposed Pad
Power - Output 4dBm
Data Rate (Max) 250kbps
Voltage - Supply 1.8V ~ 3.6V
Serial Interfaces I2C, SPI, UART, USART, USB
RF Family/Standard General ISM > 1GHz
Current - Receiving 11.3mA ~ 11.8mA
Operating Temperature -40degC ~ 85degC
Current - Transmitting 7.2mA ~ 13.8mA
Supplier Device Package 48-QFN (7x7)

Getting Started

Development is supported by the Microchip Studio (formerly Atmel Studio) and the MPLAB X IDE, with the ATSAMR21-XPRO evaluation kit serving as the primary hardware platform. Engineers can leverage the Advanced Software Framework (ASF) for validated Zigbee and 802.15.4 protocol stacks.

SAMR21G18A Family

Part NumberDifferenceStock
SAMR21G18A-AU TQFP —

Also Consider

nRF52840 nRFNordic Semiconductor - Provides multi-protocol support including Bluetooth 5 and 802.15.4 with a larger memory footprint.
MKW41Z512VHT4 NXP - A competitive ultra-low-power solution with simultaneous BLE and 802.15.4 connectivity.
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