Analog Devices AD911 Series User Manual page 8

UG-073
Figure 6. Loading DPG2 Vectors
8. After the DPG2 is correctly setup, click the Download
button ( ) in the lower right, then the Play button ( )
to begin vector playback into the AD911x or AD971x.
Evaluation Board Signal Chains
This evaluation board allows for performance to be assessed at
both the DAC output as well as the DAC and modulator signal
chain output. To include the modulator into the path, certain
jumper settings and component values must be changed. The
necessary changes are listed below as a quick reference for using
the modulator and the default settings of the DAC that will
change. Table 5 can also be referred to for further help.
Default Board Setup for Measuring DAC
The DAC settings listed are the factory defaults, however they
can be referenced when changing the board back from using the
modulator to assessing the DAC only. These values are based on
using an output current of 2 mA for the AD971x and 20 mA for
the AD911x boards.
•
J55, J56, J76, and J82 are unsoldered.
•
R95, R96, R155, and R156 are populated with 0 Ω.
•
R50 and R57 are populated with 453 Ω.
•
R111 and R112 are unpopulated.
•
R13, R14, R22, R35, R52, R53, R55, and R154 (found on
back) are unpopulated.
Evaluation Board Setup for Testing DAC and Modulator
Connect a 5 V power supply to TP16 (PWR) and TP21 (GND)
to run the modulator.
•
J55, J56, J76, and J82 are soldered.
•
R50, R57, R95, R96, R155, and R156 are unpopulated.
•
R13, R14, R52, and R53 (found on back) are populated
with 500 Ω (AD971x) or 50 Ω (AD911x).
•
R35 and R55 are populated with 100 kΩ (AD971x) or
10 kΩ (AD911x).
•
R22 and R154 are populated with 0 Ω.
Note that to set the DAC output current when using the modu-
lator, either the external shunt jumpers may be populated for
the desired setting, or the internal bias resistors may be set by
enabling and setting the appropriate codes in the SPI. Settings
for the external shunts are listed in the Analog Outputs section.
To use the internal bias resistors, see the SPI section for
information on the settings that must be changed to fully enable
and set these resistors.
SPI Software
The SPI software consists of various small sections, which are
described here as they relate to the evaluation board.
Once the setting of the part is selected, press the run button,
at the top left side of the SPI software window.
For complete descriptions of each SPI register, see the
AD9115/AD9116/AD9117
AD9717 data sheet. Note that the software graphics shown
within this user guide may not be an exact match to your
software.
Section I
This section of the SPI configures various settings for the
AD9512 clock distribution chip as follow:
•
DAC clock divide ratio and phase offset
•
Data clock divide ratio and phase offset
•
Data clock full scale delay and fine delay
Section II
This section of the SPI software configures SPI communication
and provides the following options:
•
LSB or MSB first
•
1 byte or 2 byte transmission
•
Software reset
Section III
This section of the SPI provides the following power configuration
and status information on the AD911x or AD971x:
•
Enable/disable digital LDO
•
LDO status
•
AD911x or AD971x power down
•
I or Q DAC sleep
•
Internal or external voltage reference
•
Clock to I or Q on/off
Section IV
This section of the SPI software defines the data interface to the
DUT as follows:
•
Data is twos-complement or binary
•
Data on bus is I first or Q first
•
Rising edge of data clock is used to sample I or Q data
•
Allows DCLKIO to be input and output simultaneously
Section V
This section of the SPI configures the DCLKIO pin of the DUT
as follows:
•
DCLKIO input or output
•
DCLKIO output is regular or double strength
Section VI
This section of the SPI software configures xR
internal V voltage as follows:
REF
•
Enable/disable IR
•
Set internal IR
•
Set internal voltage reference value
Rev. 0 | Page 8 of 12
Evaluation Board User Guide
or AD9714/AD9715/AD9716/
SET
and QR
SET SET
and QR values
SET SET
,
AD9114/
options and