Region-based Maximum Power#

The firmware internally maintains two tables for maximum power: worldwide table and region-based table. The worldwide table is populated by the firmware with maximum power values that the chip can transmit that meets target specifications like EVM. The region-based table has default gain value set.

  1. When certifying with user antenna, Region has to be set to Worldwide and sweep the power from 0 to 21 dBm. Arrive at max power level that is passing certification especially band-edge.

  2. These FCC/ETSI/TELEC/KCC Max power level should be loaded in end-to-end mode via WLAN User Gain table. This has to be called done every boot-up since this information is not saved inside flash. Region-based user gain table sent by application is copied onto region-based table. SoC uses this table in FCC/ETSI/TELEC/KCC to limit power and not to violate allowed limits.

  3. For Worldwide region, the firmware uses Worldwide table for Tx. For other regions(FCC/ETSI/TELEC/KCC), Firmware uses min value out of Worldwide & Region based table for Tx. Also, there will be part to part variation across chips and offsets are estimated during manufacturing flow which will be applied as correction factor during normal mode of operation.

  4. Users who have FCC/ETSI/TELEC/KCC certifications on their own antenna, have to use this frame. All other users should ignore this frame. Inappropriate use of this frame may result in violation of FCC/ETSI/TELEC/KCC or any certifications and Silicon labs is not liable for that.

See the WLAN Gain Table section for steps to program region-based maximum power of the WLAN device

See the BLE Gain Table section for steps to program the region-based maximum power of the BLE device.