EVAL-AD5590
Rev. 0 | Page 3 of 8
EVALUATION BOARD HARDWARE
OVERVIEW
The evaluation board for the AD5590 is designed to allow the
user to evaluate all the functions and performance of the AD5590
prior to designing it into a system. The evaluation board can be
used in a standalone mode with the control signals provided
through the 20-pin header, J1, or it can be connected to a PC using
the USB cable supplied with the evaluation board kit. Software
is provided, which allows the user to program the various registers
of the AD5590 with ease. The software operation is described in
the Evaluation Board Software section.
POWER SUPPLIES
The evaluation board requires a number of supplies depending
on how it is configured. Table 1 describes the function of each
of the connectors.
Table 1. Power Supply Connectors
Connector Description
J3 5 V supply connection for AD5590 Op Amp AMP0
to Op Amp AMP3
J4 5 V supply connection for AD5590 Op Amp AMP4
to Op Amp AMP7
J5 5 V supply connection for AD5590 ADC and DACs
J6 Supply connection for AD5590 V
DRIVE
pin
To provide maximum flexibility, the AD5590 evaluation board
has various links that can be used to group power supply pins
together to reduce the number of power supplies required.
Details of the link positions are given in Table 2.
Table 2. Power Supply Links
Link Description
LK33 LK33 connects the V1+ supply to the V2+ supply.
LK34 LK34 connects the V1− supply to the V2− supply.
LK35 This link performs two functions. When the link is in
Position A, the VDD supply is also connected to the
V2+ supply for AMP4 to AMP7 (and, depending on the
position of LK33, to the V1+ supply for AMP0 to AMP3).
When the link is in Position B, the USB interface is used
as the power supply for VDD.
LK35 can have links in both Position A and Position B.
This allows the evaluation board to be run completely
from the USB interface; that is, no external power
supplies are needed.
LK36 This link connects V2− to AGND. This link should be in
place if the op amps are used with a single supply.
LK37 This link selects the power supply source for the V
DRIVE
pin. In Position A, the V
DRIVE
pin is connected to the
AVDD supply. In Position B, the V
DRIVE
pin is connected
to the EXT VDRIVE connector (J6).
Table 3. Link Positions for Standalone Operation
Link Position
LK33 Inserted
LK34 Inserted
LK35 A and B
LK36 Inserted
LK37 A
REFERENCE SELECTION
The AD5590 contains two internal 2.5 V references. Either of
these references can be used to connect to V
REFA
to provide a
reference for the ADC block. LK16 selects which reference is
used. Table 4 shows the link functions.
Table 4. V
REFA
Selection Using LK16
LK16 Position Description
A Selects an external reference on the VREF SMB
connector
B V
REFIN1
/V
REFOUT1
is connected to V
REFA
C V
REFIN2
/V
REFOUT2
is connected to V
REFA
USING THE USB INTERFACE
The software provided with the evaluation board kit allows the
user to program the registers of the AD5590 via the USB interface.
It is important that the software supplied is installed on the PC
before the board is connected. See the Using the USB Software
section for more information. The USB circuitry receives its
power from the USB port of the PC and generates the required
interface signals to control the AD5590. To use the interface,
LK38 should be in place.
STANDALONE OPERATION
The evaluation board can be used as a standalone device if
required. The advantage is that it allows the user to connect the
interface pins of the AD5590 to their own DSP or microcontrol-
ler, thus allowing them to write code to operate the AD5590 as
the application requires. To use the board in standalone mode,
the connection to the USB interface must be removed. This is
achieved by removing LK38, which three-states the connections
to the AD5590 interface pins. The interface signals required to
control the AD5590 can then be provided through the 20-pin
header, J1. The pinout of J1 is shown in Table 5.
