EFR32MG21 USB Stick

 

The EFR32MG21 USB Stick reference design uses Silicon Labs' EFR32MG21 wireless IoT chip. When paired with a Linux host with a USB port such as a Raspberry Pi, it can quickly prototype a Zigbee gateway, OpenThread edge router or BLE-Mesh gateway. It can also be used To evaluate Silicon Labs' unique IEEE 802.15.4 concurrent multi-protocol gateway solution. 

For details about Silicon Labs EFR32MG21 wireless IoT chip, please refer to the official website:
https://www.silabs.com/wireless/zigbee/efr32mg21-series-2-socs

USB stick function

The EFR32MG21 USB Stick supports the Mini-Simplicity debugging programming interface, through which SEGGER J-Link can be used for firmware programming, firmware application debugging, and the network data analyzer based on Silicon Labs Simplicity Studio for PTI network data collection; it also supports the use of Linux The host performs USB Stick firmware upgrade through the USB serial port.

Optimized RF matching circuit

The default EFR32 component on the USB Stick is Xinke EFR32MG21x020, and the RF circuit impedance matching component value has been adjusted. Its transmit power can reach +19.5dBm and has passed the CE/FCC regulatory pre-test. This PCB hardware design is also suitable for Xinke 's +10dBm EFR32MG21x010 part. It only requires fine-tuning the corresponding RF front-end matching components. Please refer to the user guide attachment for details.

USB Stick PCB Board Material Options
Since the USB Stick hardware design uses a PCB trace antenna, it is necessary to choose the correct PCB board material to match our specified PCB layer stack information (below) to ensure good RF performance:

In addition, there are original AD exported Gerber files in the attachment that can be used directly. When placing an order with Shenzhen Jiali, please select the JLC7628 board closest to our requirements and the following lamination sequence: number of layers: 4, board thickness: 1.0mm 
PCB layer stack impedance For details, please refer to: https://www.sz-jlc.com/weixin/calculation/impedance.html

USB Stick transparent shell
MG21 USB Stick uses a public version of the USB flash drive enclosure with a write-protect switch. You can find multiple sellers on Taobao. Here is the purchase link for one of them :
https://item.taobao.com/item.htm ?&id=38320057218

USB Stick Firmware Update
Silicon Labs’ EFR32MG21 brand-new chip does not have a bootloader programmed. You need to program the bootloader with SEGGER J-Link first, and then you can use the Linux host-side firmware upgrade program we provide. USB interface to update USB Stick firmware.
SEGGER J-Link can use the following BGM220-EK4314A Explorer Kit from Silicon Labs. For the programming method, please refer to the user guide attachment  :  
https://www.silabs.com/development-tools/wireless/bluetooth/bgm220-explorer-kit

Copyright (c) 2022 Silicon Laboratories Inc.

Redistribution and use of the design and manufacturing files of the MG21 USB Stick reference design and the reference design's related manuals and RF test report files, with or without modification, are permitted if the following conditions are met:

1. Any redistribution of these files in any form must retain the above copyright notice, this list of conditions and the following disclaimer.

2. These files may only be used to develop or manufacture USB memory sticks for use with an MG21 or similar component validly purchased from Silicon Laboratories Inc. ("Silicon Labs") or one of its authorized resellers.

3. Silicon Laboratories Inc.'s name and its trademarks may not be used to endorse or promote products derived from these documents without prior written permission.

4. Silicon Labs provides no warranties of any kind and expressly disclaims all implied warranties or design. Users are solely responsible for ensuring that their systems comply with applicable regulatory, safety and security standards and requirements.

5. Users are solely responsible for obtaining any necessary third-party approvals and licenses to obtain any rights, including necessary patent rights. User's use of any USB Stick or other product or system developed using these files.

These documents are provided "as is". No warranties, express or implied, including, but not limited to, the implied warranties of merchantability, fitness for a particular purpose and non-infringement, are disclaimed. In no event shall SILICON LABS be liable for any direct, indirect, incidental, special, exemplary or consequential damages (including, without limitation, procurement of substitute goods or services; loss of use, data or profits; or business interruption) regardless of ARISING OUT OF ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) IN ANY WAY ARISING FROM THE USE OF THESE DOCUMENTS, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.