Datasheet

EVAL-AD7328CB
Rev. 0 | Page 3 of 16
EVALUATION BOARD HARDWARE
OPERATING THE AD7328 EVALUATION BOARD
Power Supplies
When using this evaluation board with the EVAL-CONTROL-
BRD2, all supplies are provided from the controller board
through the 96-way connector.
When using the board as a standalone unit, external supplies
must be provided. This evaluation board has five power supply
inputs: EXT_V
DD
, AGND, +12 V, −12 V, and AGND. If the
evaluation board is used in standalone mode, a 2.75 V to 5.25 V
supply must be connected to the EXT_V
DD
input. The +12 V
and −12 V supplies are required for the high voltage analog
input section on the AD7328 and the AD797 op amps. The
supplies are decoupled to the ground plane with 10 μF tantalum
and 0.1 μF multilayer ceramic capacitors at the point where they
enter the board. The supply pins of the op amps and the
reference are also decoupled with 10 μF tantalum and 0.1 μF
ceramic capacitors as are Pin V
DD
, Pin V
SS
, and Pin V
CC
of the
AD7328.
LINK OPTIONS
There are 26 link options that must be set for the required
operating setup before using the evaluation board. The
functions of the options are outlined in
Table 1.
SETUP CONDITIONS
Care should be taken before applying power and signals to the
evaluation board to ensure that all link positions are as per the
required operating mode.
Table 2 shows the position in which the links are set when the
evaluation board is packaged.
Table 1.
Link No. Function
LK1 This link option controls the program pin of the AD780 voltage reference.
LK2 This link selects the source of the REF
IN
voltage to be applied to the REF
IN
pin of the AD7328.
When in Position A, the AD780 supplies the 2.5 V reference to the AD7328.
When in Position B, the REFIN is supplied through the J4 SMB connector.
LK3 This link selects the source of the V
CC
supply for the AD7328.
When in Position A, the V
CC
supply is taken from the 96-way connector of the EVAL-CONTROL-BRD2.
When in Position B, the V
CC
supply is taken from the external J2 connector.
LK4 This link option selects the source of the V
DRIVE
voltage for the AD7328.
When in Position A, the V
DRIVE
voltage is taken from the external J3 V
DRIVE
socket.
When in Position B, the V
DRIVE
voltage is taken from the 96-way connector of the EVAL-CONTROL-BRD2.
When in Position C, the V
DRIVE
voltage is tied to the V
CC
voltage.
LK5
This link option selects the source of the
CS signal.
When in Position A, the
CS signal is taken from the 96-way connector of the EVAL-CONTROL-BRD2.
When in Position B, the
CS signal is taken from the J5 CS SMB socket.
LK6 This link selects the source of the SCLK signal for the AD7328.
When in Position A, the SCLK signal comes from the J6 SMB socket.
When in Position B, the SCLK signal comes from the 7S04 inverter, which is an inverted SCLK signal
from the 96-way connector.
When in Position C, the SCLK signal is taken directly from EVAL-CONTROL-BRD2 through the
96-way connector.
LK7 This link option selects the source of the DIN signal to the AD7328.
When in Position A, the DIN signal is taken from the 96-way connector to the EVAL-CONTROL-BRD2.
When in Position B, the DIN signal is taken from the J7 DIN SMB socket.
LK8 This link option selects the destination of the DOUT signal from the AD7328.
When in Position A, the DOUT signal goes to the 96-way connector to the EVAL-CONTROL-BRD2.
When in Position B, the DOUT signal goes to the DOUT J8 SMB socket.
LK9, LK11, LK13, LK15,
LK17, LK19, LK21, LK23
These link options add a 51 Ω termination resistor to AGND at the V
IN
0 to V
IN
7 input sockets.
LK10, LK12, LK14, LK16,
LK18, LK20, LK22, LK24
These link options select the input to the AD797 op amp.
When in Position A, the AD797 noninverting input is tied to the SMB socket.
When in Position B, the AD797 noninverting input is tied to AGND.