EFR32 Thunderboard-style boards


There are a couple of very similar boards, which we categorize as “Thunderboard-style boards”. The name can be seen on some of Silicon Labs products that use boards of this style, such as EFR32™ Blue Gecko Starter Kit, a.k.a Thunderboard EFR32BG22.

Those boards contains an MCU from the EFR32BG family built on ARM® Cortex®-M33F processor with low power capabilities.

For an example of such board, refer to the following site:

Currently the following devices are considered “Thunderboard-style”:

Serial Port

The SoCs used on these boards have two USARTs. USART1 is connected to the board controller and is used for the console.

Programming and Debugging


Before using the kit the first time, you should update the J-Link firmware from J-Link-Downloads


The Thunderboard boards include J-Link serial and debug adapters built into the board. The adapter provides:

For detailed instructions regarding flashing, refer to documentation of a specific device.