Energy Friendly Front End Module (EFF) Utility#

RAIL EFF Utility#

This optional software component can be enabled to include default functionality related to EFF configuration.

The EFF is a high-performance, transmit/receive (T/R) front end module (FEM) for sub-GHz EFR32 devices. The device transmit chain features a power amplifier and a switched attenuator to extend the dynamic range of the device. The device receive chain features a low-noise amplifier (LNA), a voltage peak detector to determine presence of blockers and an LNA position that can be selected to be either before or after the external filter to optimize system noise floor in the absence of blockers.

When using a Silicon Labs-developed board with an EFF, the configuration options for this software component are set up automatically based on the selected board. When using a custom board, manually configure the configuration options.

Configuration Options#

The following configuration options can be changed:

  • Enable/disable Rural LNA Mode.

  • Enable/disable Urban LNA Mode.

  • Enable/disable Bypass LNA Mode.

  • Configure the maximum continuous transfer power.

  • Configure the maximum transmit duty cycle.

The following hardware pins must be enabled to use the EFF and are fixed to specific GPIO pins on your chip that cannot be changed:

  • The CTRL0 GPIO pin.

  • The CTRL1 GPIO pin.

  • The CTRL2 GPIO pin.

  • The CTRL3 GPIO pin.

  • The SENSE GPIO pin.

The following hardware options can be set based on your design:

  • Configure the TEST GPIO pin.

  • Specify the part number of the attached EFF device.