Hello, I need some input on TX Power configuration for nRF5340+nRF21540.
(We are on NCS 2.7, and not yet migrated ot using sysbuild. Still using parent+child image.)
Seems there are multiple ways of configuring TX power, via code and Kconfig.
Need help in being able to control the output of nRF5340, gain for nRf21540 and hence TX power at antenna.
We are using nRF21540 GPIO+SPI configuration, and I have set PA gain to be 20 dB.
I have the following MPSL Config in .config for Netcore image:
#
# Multiprotocol service layer (MPSL)
#
# CONFIG_MPSL_FEM_ONLY is not set
CONFIG_MPSL_FEM_ANY_SUPPORT=y
CONFIG_MPSL_FEM_NRF21540_GPIO_SUPPORT=y
CONFIG_MPSL_FEM_NRF21540_GPIO_SPI_SUPPORT=y
CONFIG_MPSL_FEM_NCS_SUPPORTED_FEM_USED=y
CONFIG_MPSL_FEM_API_AVAILABLE=y
CONFIG_MPSL_FEM=y
# CONFIG_MPSL_FEM_NRF21540_GPIO is not set
CONFIG_MPSL_FEM_NRF21540_GPIO_SPI=y
CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB=20
CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB_POUTA=20
CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB_POUTB=10
CONFIG_MPSL_FEM_NRF21540_RX_GAIN_DB=13
# CONFIG_MPSL_FEM_NRF21540_RUNTIME_PA_GAIN_CONTROL is not set
CONFIG_MPSL_FEM_POWER_MODEL=y
CONFIG_MPSL_FEM_POWER_MODEL_NRF21540_USE_BUILTIN=y
CONFIG_MPSL_FEM_BUILTIN_POWER_MODEL_UPDATE_PERIOD=2000
CONFIG_MPSL_FEM_DEVICE_CONFIG_254=y
CONFIG_MPSL_FEM_INIT_PRIORITY=50
CONFIG_MPSL_THREAD_COOP_PRIO=6
CONFIG_MPSL_TIMESLOT_SESSION_COUNT=0
# CONFIG_MPSL_ASSERT_HANDLER is not set
# CONFIG_MPSL_TRIGGER_IPC_TASK_ON_RTC_START is not set
CONFIG_MPSL_LOW_PRIO_IRQN=26
# end of Multiprotocol service layer (MPSL)
I am setting Gain of 20 dB with this config.
I want to configure +3 dBm TX power on nRF5340 to get +23 dBm TX power at the antenna.
If I set CONFIG_BT_CTLR_TX_PWR_ANTENNA=23
I don't have CONFIG_BT_CTLR_TX_PWR_DBM in .config for netcore image, what will the value of nRF5340 TX power output be in this case?
1) Will it be 3 dBm even though .config does not say it?
2) Are there any additional settings or voltage requirements needed to enable +3dbm?