Analog Devices EVAL-AD5325DBZ, Руководство пользователя

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EVAL-AD5325DBZ User Guide UG-976
Rev. A | Page 3 of 13
EVALUATION BOARD HARDWARE
POWER SUPPLIES
The nano DAC® EVAL-MBnanoDAC-SDZ motherboard
supports single and dual power supplies.
The
EVAL-AD5325DBZ 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 board. The
AGND and DGND planes are connected at one location on the
EVAL-MBnanoDAC-SDZ . It is recommended that AGND and
DGND not be connected elsewhere in the system to avoid
ground loop problems.
All supplies are decoupled to ground with 10 µF tantalum and
0.1 µF ceramic capacitors.
Table 1. Power Supply Connectors
Connector No. Label Voltage
J5, Pin 1 (J5-1) VDD Analog positive power supply, V
DD
Single and dual supply, 5.5 V
J5, Pin 2 (J5-2) AGND Analog ground
J5, Pin 3 (J5-3) VSS Analog negative power supply, V
SS
Dual supply, −5.5 V
J6, Pin 1 (J6-1) VLOGIC Digital supply from 1.8 V to V
DD
J6, Pin 2 (J6-2) DGND Digital ground
MOTHERBOARD LINK OPTIONS
Various link options are incorporated in the EVAL-
MBnanoDAC-SDZ and must be set for the required operating
conditions before using the board. Table 2 describes the
positions of the links to control the evaluation board via the
SDP-B 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 and Table 4 match the evaluation
board imprints (see Figure 11).
Table 2. Link Options Setup for SDP-B Control (Default)
Link Number Position
REF1 2.5V
REF2 EXT
REF3 EXT
REF4 EXT
LK5 C
LK6 +3.3V
LK7 B
DAUGHTER BOARD LINK OPTIONS
The EVAL-AD5325DBZ daughter board has one link option.
This link sets the least significant bit (LSB) of the I 2 C address of
the DAC. Table 3 describes the function of the link. Set LK1 to
Position B for proper device operation.
Table 3. Link Options for Daughter Board
Link Number Label Position
LK1 A0 A (high)
B (low, default)
Table 4. Link Functions
Link Number Function
REF1, REF2, REF3, 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 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 V
LOGIC
voltage source.
Po3.3V selects the digital voltage source from the SDP-B board (3.3 V).
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.