EFR32FG14 2400/868 MHz Dual Band
13 dBm Radio Board
BRD4257B Reference Manual
The BRD4257B Flex Gecko Radio Board enables developers to develop proprietary
wireless applications. The board contains a dual-band Flex Gecko Wireless System-on-
Chip and it is optimized for operating at 13 dBm output power. For the 2.4 GHz band
with the on-board printed antenna and UFL connector, radiated and conducted testing is
supported. For the 868 MHz band, the on-board SMA connector enables conducted
testing and attachment of external whip antenna for radiated tests.
The BRD4257B Flex Gecko Radio Board plugs into the Wireless Starter Kit Mainboard,
which is included with the Flex Gecko Starter Kit and gives access to display, buttons
and additional features from Expansion Boards. With the supporting Simplicity Studio
suite of tools, developers can take advantage of graphical wireless application develop-
ment and visual energy profiling and optimization. The board also serves as an RF ref-
erence design for applications targeting 2.4 GHz and 868 MHz dual band wireless oper-
ation with 13 dBm output power.
RADIO BOARD FEATURES
• Wireless SoC:
EFR32FG14P233F256GM48
• CPU core: ARM Cortex
®
-M4 with FPU
• Flash memory: 256 kB
• RAM: 32 kB
• Operation frequency: 2.4 GHz + 868 MHz
• Transmit power: 13 dBm
• 2.4 GHz: Integrated PCB antenna, UFL
connector (optional)
• 868 MHz: Single SMA connector both for
transmit and receive
• Crystals for LFXO and HFXO: 32.768 kHz
and 38.4 MHz
• 8 Mbit low-power serial flash for over-the-
air updates
This document contains a brief introduction and description of the BRD4257B Radio
Board features, focusing on the RF sections and performance.
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