EFR32MG21 in Silicon Labs EFR32 / EFM32 Family
The EFR32MG21 series from Silicon Labs is a high-performance sub-family of the Mighty Gecko Series 2 platform. Optimized for line-powered IoT applications, these multiprotocol Wireless SoCs integrate an ARM Cortex-M33 core with dedicated security subsystems and high-output radio power. They are engineered to support 2.4 GHz mesh networking protocols including Zigbee, Thread, and Matter, alongside Bluetooth Low Energy, providing robust connectivity for smart home, commercial, and industrial automation environments.
Variants in This Sub-Family
Comparing specs that differ across variants.
| Part Number | Memory | Interfaces | Frequency | Modulation | RF Family/Standard | Rx Current | Stock |
|---|---|---|---|---|---|---|---|
| EFR32MG21A020F1024IM32-B (Silicon Labs) | 1024k | ADC, GPIO, I2C, I2.. | 2.4GHz | GFSK, O-QPSK | Bluetooth | 8.8mA | 1,954 |
| EFR32MG21B020F1024IM32-B (Silicon Labs) | 1MB | I2C, I2S, SPI, IrD.. | 2.4GHz | DSSS, GFSK, O-QPSK | 802.15.4, Bluetooth | 8.8mA | 2,302 |
| EFR32MG21A020F768IM32-B (Silicon Labs) | 768k | ADC, GPIO, I2C, I2.. | 2.4GHz | GFSK, O-QPSK | Bluetooth | 8.8mA | 405 |
Variants within the EFR32MG21 family are distinguished primarily by flash memory capacity (512 KB to 1024 KB), RAM size (64 KB to 96 KB), and maximum RF transmit power (+10 dBm vs +20 dBm). The 'A' and 'B' revisions denote different feature sets regarding hardware security levels, with Secure Vault features typically found on 'B' series variants to provide advanced anti-tamper and secure key storage capabilities.
