Auxiliary Converters And Temperature Sensor; Auxiliary Dac (Auxdac); Auxiliary Adc (Auxadc) - Analog Devices ADRV9001 User Manual

Preliminary Technical Data

AUXILIARY CONVERTERS AND TEMPERATURE SENSOR

The ADRV9001 device features auxiliary data converters including four 12-bit auxiliary Digital-to-Analog converters (AuxDAC) and
four 12-bit auxiliary analog-to-digital converter (AUXADC_x). An integrated diode-based temperature sensor is available to readback
the approximate die temperature of the device.
These features are included to simplify control tasks and reduce pin count requirements on the baseband processor by offloading these
tasks to the ADRV9001. Example usage of the auxiliary converters include static voltage measurements performed by the AuxADC and
flexible voltage control performed by the AuxDAC. This section outlines the operation of these features along with API command for
configuration and control.

AUXILIARY DAC (AUXDAC)

There are four, independent, 12-bit AuxDACs integrated in the ADRV9001. The auxiliary DACs have an output voltage of
approximately 0.05 V to VAGPIO_1P8 – 0.05V. The AuxDACs use the enumeration adi_adrv9001_AuxDac_e when referenced in the
API. The pins used for the AuxDAC features are listed in Table 80.
Table 80. AuxDAC Pin Mapping and adi_adrv9001_AuxDac_e Enum Description
Aux DAC Number Pin Name
AUXDAC[0] AGPIO_0
AUXDAC[1] AGPIO_1
AUXDAC[2] AGPIO_2
AUXDAC[3] AGPIO_3
The capacitive load of the AuxDAC pins should not exceed more than 100 pF otherwise stability issues may occur.
The AuxDAC uses the AGPIO pins on the device. Conflicts between AGPIO and AuxDAC functionality may occur. In case of these
conflicts, the AuxDAC takes precedence over all other AGPIO functionality when AuxDAC is enabled for a specific pin. When the
AuxDAC is disabled, the configured AGPIO functionality is applied. The AuxDAC can be enabled one pin at a time to allow flexibility
between AuxDAC and AGPIO functionality.
The AuxDAC is typically used in applications requiring analog control signals. The data interface used to set the output level of the
AuxDAC is SPI (API) or internal LUT (power amplifier RAMP function enabled) based. There is no CMOS/LVDS data interface to
provide input data to the AuxDAC.
The (ideal) output voltage expressed on the AuxDAC is based on the following equation (in volts):
AuxDacValue
= +
V 0.9
AUXDAC
where AuxDacValue is the 12-bit digital code applied to the AuxDAC.
The AuxDAC is not a precision converter, it is best used in feedback systems. Above AuxDAC output equation is to be characterized,
AuxDAC output voltage versus input codes for a full range code sweep of the AuxDAC will be added in the future after necessary
characterization.
AuxDAC API Programming
A set of API commands are provided to set and inspect the AuxDAC, which is summarized in Table 81.
Table 81. AuxDAC API list
AuxDAC Function Name
adi_adrv9001_AuxDac_Configure
adi_adrv9001_AuxDac_Inspect
adi_adrv9001_AuxDac_Code_Set
adi_adrv9001_AuxDac_Code_Get

AUXILIARY ADC (AUXADC)

ADRV9001 contains four dedicated AuxADCs denoted as: AUXADC_0, AUXADC_1, AUXADC_2, and AUXADC_3. The AuxADC is
a 12-bit output delta-sigma converter useful for measuring DC and near-DC signals (<8KHz). The input voltage range of the AuxADC is
150mV to 800mV. Readback of the AuxADC input voltage is performed using API commands.
Pin Number
F12
F10
F3
F5
−
2048
×
1.7
4096
Description
Sets the configuration for AuxDACs, enable/disable the selected AuxDAC
Gets the configuration of selected AuxDAC
Sets 12 bit DAC code of selected AuxDAC
Reads the DAC word of selected AuxDAC
Enum Name
ADI_ADRV9001_AUXDAC0
ADI_ADRV9001_AUXDAC1
ADI_ADRV9001_AUXDAC2
ADI_ADRV9001 _AUXDAC3
Rev. PrA | Page 183 of 253
UG-1828