https://www.silabs.com/wireless/bluetooth/efr32bg1-series-1-socs/device.efr32bg1p333f256gm48
EFR32BG1P333F256GM48 Bluetooth LE Chip - Silicon Labs - Silicon Labs
The EFR32BG1P333F256GM48 (EFR32BG1 Series 1) Bluetooth LE chip includes a 40 MHz ARM Cortex-M4 MCU and provides 20 dBm maximum power output.
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