Digital Gain Control And Interface Gain Api Programming - Analog Devices ADRV9001 User Manual

Preliminary Technical Data
from -36dB to 18dB and for WB applications, the interface gain is from −36 dB to 0 dB in 6 dB step size. This mode could be utilized
especially when baseband processor input signal clipping is observed by the user.

DIGITAL GAIN CONTROL AND INTERFACE GAIN API PROGRAMMING

The API function adi_adrv9001_Rx_InterfaceGain_Configure() is provided to configure the interface gain. The configuration structure
adrv9001_RxInterfaceGainCtrl_t is defined as the following:
typedef struct adrv9001_RxInterfaceGainCtrl
{
adi_adrv9001_RxInterfaceGainUpdateTiming_e updateInstance;
gain control has to be updated. 0: To be updated at start of next frame 1: To be updated
immediately */
adi_adrv9001_RxInterfaceGainCtrlMode_e
value 1: Uses external Rx interface gain value. Gain value has to be provided in this case. */
adi_adrv9001_RxGainTableType_e
Compensation table
adi_adrv9001_RxInterfaceGain_e
18dB, 0x1 = 12dB, 0x2 = 6dB, 0x3 = 0dB, 0x4 = -6dB, 0x5 = -12dB, 0x6 = -18dB, 0x7 = -24dB, 0x8 =
-30dB, 0x9 = -36dB). */
} adrv9001_RxInterfaceGainCtrl_t
It is clear from the above that there are 2 interface gain control modes, which are internal (automatic) control and external control. In
addition, there are 2 options to apply the interface gain. The first option is to apply it at the start of the next frame and the second option
is to apply it immediately. The interface gain could be selected from -36dB to 18dB in 6dB step size, a total of 10 options, which is defined
by "adi_adrv9001_RxInterfaceGain_e" as the following:
typedef enum adi_adrv9001_RxInterfaceGain
{
ADI_ADRV9001_RX_INTERFACE_GAIN_18_DB = 0,
ADI_ADRV9001_RX_INTERFACE_GAIN_12_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_6_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_0_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_6_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_12_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_18_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_24_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_30_DB,
ADI_ADRV9001_RX_INTERFACE_GAIN_NEGATIVE_36_DB,
} adi_adrv9001_RxInterfaceGain_e
Note as discussed before, depending on the gain table type and the bandwidth of the application, the interface gain could be limited to a
subset of the 10 options. This API must be called in the "CALIBRATED" state.
To change the interface gain on the fly while the channels are operation, the API function adi_adrv9001_Rx_InterfaceGain_Set() could
be used. The gain should be selected from one of the 10 options.
The following table summarizes the list of API functions currently available for digital gain control and interface gain. For more up-to-
dated information and detailed descriptions, please refer to API doxygen document.
Table 66. A List of Rx Interface Gain Control APIs
Rx Gain API Function Name
adi_adrv9001_Rx_Rssi_Read
adi_adrv9001_Rx_InterfaceGain_Configure
adi_adrv9001_Rx_InterfaceGain_Set
adi_adrv9001_Rx_InterfaceGain_Inspect
adi_adrv9001_Rx_InterfaceGain_Get
controlMode; /* 0: Uses internal Rx interface gain
gainTableType; /* 0: Gain Correction table 1: Gain
gain;
/*!<
/*!<
/*!<
/*!<
/*!<
/*!< -12 dB */
/*!< -18 dB */
/*!< -24 dB */
/*!< -30 dB */
/*!< -36 dB */
Description
Reads back the RSS status for the given channel
Sets the Rx interface gain control configuration parameters for the given Rx channel
Sets the Rx interface gain for the given Rx channel
Gets the Rx interface gain control configuration parameters for the given Rx channel
Gets the Rx interface gain for the given Rx channel
Rev. PrA | Page 145 of 253
/* Time at which Rx interface
/* a value between 0 and 9 (0x0 =
18 dB */
12 dB */
6 dB */
0 dB */
-6 dB */
UG-1828