Auxiliary Converters And Temperature Sensor; Auxiliary Digital-To-Analog Converter (Auxdac) - Analog Devices ADRV9001 User Manual

Reference Manual

AUXILIARY CONVERTERS AND TEMPERATURE SENSOR

The ADRV9001 device features auxiliary data converters, including four 12-bit auxiliary digital-to-analog converters (AuxDAC) and four 10-bit
auxiliary analog-to-digital converters (AUXADC). There is an integrated diode-based temperature sensor to read back 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. An example usage of the auxiliary converters includes 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 the API commands for configuration
and control.
AUXILIARY DIGITAL‐TO‐ANALOG CONVERTER (AUXDAC)
The ADRV9001 has four independent, 12-bit AuxDACs. The auxiliary DACs have an output voltage of approximately 0.05 V to VAGPIO_1P8
– 0.05 V. The AuxDACs use the enumeration adi_adrv9001_AuxDac_e when referenced in the API.
AuxDAC features.
Table 101. 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, there can be stability issues.
The AuxDAC uses the AGPIO pins on the device. There can be conflicts between the AGPIO and AuxDAC functionality. In case of these
conflicts, the AuxDAC takes precedence over all other AGPIO functionality when the AuxDAC is enabled for a specific pin. When the AuxDAC
is disabled, the configured AGPIO functionality is applied. Enable the AuxDAC one pin at a time for flexibility between the 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.
V = 0.9 +
The (ideal) output voltage expressed on the AuxDAC is based on the following equation (in volts):
AuxDacValue − 2048
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.
voltage characterization plot. The AuxDAC output represents good linear behavior when the DAC code is within the range Code_min_linear and
Code_max_linear. Table 102 shows the detailed test data summary, which is performed with the following conditions:
Sample set: 20 AUX DACs
►
5 parts
►
4 AUX DACs per part
►
Nominal process corner
►
Nominal supplies
►
Measured at ambient temperatures of 25°C, 85°C, and -40°C.
►
analog.com
Pin Number
F12
F10
F3
F5
× 1.7
4096
Table 101
Enum Name
ADI_ADRV9001_AUXDAC0
ADI_ADRV9001_AUXDAC1
ADI_ADRV9001_AUXDAC2
ADI_ADRV9001 _AUXDAC3
Figure 215 shows the DAC code and corresponding DAC output
ADRV9001
shows the pins used for the
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