Analog Devices ADRV9005 Reference Manual page 145

Reference Manual
TRANSMITTER SIGNAL CHAIN
ADI_ADRV9001_TX_ATTENUATION_CONTROL_MODE_SPI = 1,
ADI_ADRV9001_TX_ATTENUATION_CONTROL_MODE_PIN = 3,
ADI_ADRV9001_TX_ATTENUATION_CONTROL_MODE_CLGC = 4,
} adi_adrv9001_TxAttenuationControlMode_e
The following subsections discuss the first three modes. For the CLGC mode, see the
Bypass Mode
Select the bypass mode when the transmitter attenuation mode is set as "ADI_ADRV9001_TX_ATTENUATION_CONTROL_MODE_BY-
PASS". In this mode, the transmitter attenuation functionality is not used, which means 0 dB total transmitter attenuation.
SPI Mode
Select the serial peripheral interface (SPI) mode when the transmitter attenuation mode is set as "ADI_ADRV9001_TX_ATTENUATION_CON-
TROL_MODE_SPI". In this mode, set the transmitter attenuation value through the API command "adi_adrv9001_Tx_Attenuation_Set()".
The SPI mode consists of two options: the TDD ramp and constant-step size modes. The TDD ramp mode is designed for power ramping in
TDD systems. The constant-step size mode allows to control an exact constant gain step size to reach the targeted attenuation level.
TDD Ramp Mode
The time division duplex (TDD) ramp mode is designed for use in TDD systems. Program an "On power" and "Off power" for the next time
slot. Control the ramp rate through a step size (tdd_ramp_step_size) and wait duration (tdd_ramp_wait_duration) between the steps. Initiate the
ramp up or down through API commands. Note that these user interactions are currently not supported.
Constant-Step Size Mode
In the constant-step size mode, the transmitter attenuation controller ramps to the new transmitter attenuation value immediately after
it is set through an API command. Again, control the slope through a step size (const_step_mode_step_size) and wait duration
(const_step_mode_wait_duration) between the steps.
analog.com
Figure 140. TDD Ramp Profile
Figure 141 shows a typical output power transient for this mode.
Figure 141. Constant Step Mode
Closed Loop Gain Control (CLGC)
Figure 140 depicts a typical TDD ramp.
ADRV9001
section.
Rev. A | 145 of 377