Datasheet

EVAL-AD7352/AD7356/AD7357
Rev. 0 | Page 3 of 16
EVALUATION BOARD HARDWARE
POWER SUPPLIES
When using this evaluation board with the EVAL-CED1Z, all
supplies are provided from the converter evaluation and
development (CED) board through the 96-way connector.
When using the board as a standalone unit, external supplies
must be provided. This evaluation board has the following
power supply inputs: V
DD
(+2.5 V), V
DRIVE
(+3.3 V), V+ (5 V),
V−
(−5 V), AGND, and DGND.
The supply pins of all the op amps and references are decoupled
to AGND with a 10 μF tantalum capacitor and a 0.1 μF ceramic
capacitor. The AD7352, AD7356, and AD7357 V
DD
and V
DRIVE
supply pins are also decoupled to AGND with 10 μF tantalum
capacitors and 0.1 μF multilayer ceramic capacitors.
Extensive ground planes are used on this board to minimize the
effect of high frequency noise interference. There are two ground
planes: AGND and DGND. These are connected at one location
close to the AD7352, AD7356, or AD7357.
LINK OPTIONS
There are four link options that must be set for the required
operating setup before using the evaluation board. The
functions of each option are outlined in Table 1.
There are an additional 21 solder link options for various functions.
These link options are outlined in Table 2 . These options are
initially set up to be EVAL-CED1Z compatible on all boards.
Table 1. Link Option Functions
Link No. Function
LK1 This link option is used to select the source of the V
DD
(+2.5 V) supply, which is used to power the AD7352, AD7356, and AD7357.
In Position A, V
DD
is supplied from the CED board through the 96-way connector.
In Position B, V
DD
is supplied from an external source via Power Connector J11.
LK2 This link option selects the source of the V
DRIVE
(+3.3 V) supply for the AD7352, AD7356, and AD7357.
In Position A, V
DRIVE
is supplied from the CED board.
In Position B, V
DRIVE
must be supplied from an external source via Power Connector J12.
LK3 This link option selects the source of the V− (−5 V) supply for the op amps.
In Position A, V− must be supplied from an external source via Power Connector J14.
In Position B, V− is supplied from the CED board.
LK4 This link option selects the source of the V+ (+5 V) supply for the op amps.
In Position A, V+ must be supplied from an external source via Power Connector J14.
In Position B, V+ is supplied from the CED board.
Table 2. Solder Link Option Functions
Link No. Function
S1
This link selects the source of the SCLK signal for the AD7352, AD7356, and AD7357. If this link is closed, SCLK must be supplied
from an external source via SCLK SMB Connector J8.
S2
This link selects the source of the SCLK signal for the AD7352, AD7356, and AD7357. If this link is closed, SCLK is supplied by the
CED board.
S3
This link selects the destination of the SDATA
A
signal from the AD7352, AD7356, and AD7357. If this link is closed, the SDATA
A
signal goes to SDATA
A
SMB Connector J9.
S4
This link selects the destination of the SDATAA signal from the AD7352, AD7356, and AD7357. If this link is closed, the SDATA
A
signal goes to the CED board through the 96-way connector.
S5
This link selects the destination of the SDATAB signal from the AD7352, AD7356, and AD7357. If this link is closed, the SDATA
B
signal goes to SDATA
B
SMB Connector J10.
S6
This link selects the destination of the SDATAB signal from the AD7352, AD7356, and AD7357. If this link is closed, the SDATA
B
signal goes to the CED board through the 96-way connector.
S7
This link selects the source of the CS
signal for the AD7352, , and . If this link is closed, AD7356 AD7357 CS must be supplied from
an external source via SCLK SMB Connector J7.
S8
This link selects the source of the CS
signal for the AD7352, , and . If this link is closed, AD7356 AD7357 CS is supplied by the
CED board.
S9 If a bipolar analog input source is used, this link should be open. If a unipolar analog input source is used, this link should be closed.
S11
This link selects the source of the common-mode input for the AD8138 op amp that drives ADC A on the AD7352, AD7356, and
AD7357. If this link is closed, the common mode is supplied from an external source via EXT COM A Connector J3.
S12
This link selects the source of the SCLK signal for the AD7352, AD7356, and AD7357. If this link is closed, SCLK is supplied by the
CED board.