EVAL-AD5321DBZ User Guide UG-972
Rev. 0 | Page 3 of 12
EVALUATION BOARD HARDWARE
POWER SUPPLIES
The nanoDAC® EVA L-MBnanoDAC-SDZ motherboard
supports single and dual power supplies.
The E VA L-AD5321DBZ evaluation board can be powered
either from the SDP-B port or externally by the J5 and J6
connectors, as described in Table 1.
Both AGND and DGND inputs are provided on the E VA L-
AD5321DBZ. The AGND and DGND planes connect at one
location on the EVA L-MBnanoDAC-SDZ. It is recommended
that AGND and DGND do not connect elsewhere in the system
to avoid ground loop problems.
All supplies are decoupled to ground with a 10 µF tantalum
capacitor and 0.1 µF ceramic capacitor.
Table 1. Power Supply Connectors
Connector Label Voltage
J5, Pin 1 (J5-1) VDD Analog positive power supply, V
DD
;
5.5 V single and dual supply
J5, Pin 3 (J5-3) VSS Analog negative power supply, V
SS
;
−5.5 V dual supply
J6, Pin1 (J6-1) VLOGIC Digital supply from 1.8 V to V
DD
J6, Pin 2 (J6-2) DGND Digital Ground
Link Options
A number of link options are incorporated in the EVA L -
MBnanoDAC-SDZ and must be set for the required operating
conditions before using the EVA L-AD5321DBZ. Table 2
describes the positions of the links to control the evaluation
board via the SDP-B controller board using a PC and external
power supplies. The functions of these link options are described in
detail in Table 4. The positions listed in Table 2 to Table 4 match
the evaluation board imprints (see Figure 10).
Table 2. Link Options Setup for SDP-B Control (Default)
Link Number Position
REF1 EXT
REF2 EXT
REF3 EXT
REF4 EXT
LK6 +3V3
LK7 B
EVAL-AD5321DBZ DAUGHTER BOARD LINK
OPTIONS
The EVA L -AD5321DBZ daughter board has a link option. This
link sets the LSB of the I
2
C address of the DAC. Table 3 describes
the function of this link. For proper device operation, set the
LK1 position to B.
Table 3. Link Options for Daughterboard
Link Pin Position
LK1 A0 A (high)
B (low, default)
Table 4. Link Functions
Link Number Position
REF1 to REF4 These links select the reference source.
Position EXT selects an off board voltage reference via the appropriate EXT_REF connector.
Position VDD selects V
DD
as the reference source.
Position 4.096V selects the on-board 4.096 V reference as the reference source.
Position 2.5V selects the on-board 2.5 V reference as the reference source.
Position 5V selects the on-board 5 V reference as the reference source.
LK5 This link selects the positive DAC analog voltage source.
Position A selects the internal voltage source from the SDP-B controller board.
Position B selects the internal voltage source +3.3 V from the ADP121 on the motherboard.
Position C selects an external supply voltage, V
DD
.
LK6 This link selects the VLOGIC voltage source.
Position +3V3 selects the digital voltage source from the SDP-B board (+3V3).
Position VLOGIC selects an external digital supply voltage, V
LOGIC
.
LK7 This link selects the negative DAC analog voltage source.
Position A selects V
SS
.
Position B selects AGND.
