Preliminary Technical Data
UG-1828
Rev. PrC | Page 19 of 338
Functionality
Constrains and Limitations
DPD
The DPD functionality can be used in the 1T1R TDD mode. Maximum channel bandwidth that DPD can support is
limited by ADRV9001 RF bandwidth divided by 3 or by 5. The DPD operation can be performed by ADRV9001 or Rx
data can be sent to baseband processor via Rx data port during Tx operation. Rx path used during DPD operation to
perform Tx observation is also used by the Tx tracking calibrations. In case of external DPD, user must ensure that
access to the Rx path during Tx slots is time-shared between external DPD operation and Tx calls.
Calibrations
During Rx initialization sequence, the user needs to ensure that there are no signals present at the Rx input (external
LNA should be disabled) and appropriate termination should be present at the LNA output to avoid reflections of Rx
calibration tones. The maximum input signal amplitude must not exceed −82 dBm/MHz for wideband modes, TBD
dBm/MHz for narrowband modes. During Tx initialization sequence, user needs to ensure that Power Amplifier is
powered down to avoid unwanted emission of Tx calibration tones at the antenna. ADRV9001 needs to access Rx
datapath during Tx time slots for Tx tracking calibration to operate. If user use Tx observation path with DPD
functionality performed by baseband processor, then access to the Rx datapath during Tx slots must be time-shared
between DPD operation and Tx calibrations.
AGPIOs
Analog GPIOs (operating at 1.8 V level) can be used as read or write digital levels of in the end user system. AGPIOs
can be used to control states of external components (for example, RF Switch) or read back digital logic levels from
external components.
DGPIOs
Digital GPIOs can be used to perform real-time monitoring of states of internal ADRV9001 blocks. Digital GPIOs
operating as inputs can allow user to control Rx gain, Tx attenuation, AGC operation and other elements of ADRV9001
TRx. Depending on the ADRV9001 operation up to 4 GPIOs may be used by data port interface.
AuxADC
AuxADC can be used to monitor analog voltage (for example, temperature sensor). Maximum AuxADC input voltage
must not exceed 0.9 V.
AuxDAC
AuxDAC can be used to control the VCXO responsible for generating the ADRV9001 device clock, generate pre-
configured ramp up/down signal that can be used to control power amplifier bias, control any circuitry that requires
analog control voltage up to 1.8 V.
DEV_CLK_OUT
ADRV9001 provides divided down version of DEV_CLK reference clock input signal on the DEV_CLK_OUT output. This
output is intended to provide reference clock signal to the digital components in the overall system. This output can
be configured to be active after power up and before ADRV9001 configuration stage.
Multichip Sync
If there is no need for multichip synchronization, the ADRV9001 can be initialized using API functions only.