Analog Devices EVAL-AD7276SDZ, Руководство пользователя

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EVAL-AD7276SDZ User Guide UG-450
Rev. 0 | Page 11 of 20
EVALUATION BOARD CIRCUITRY
ANALOG INPUTS
Two analog input options are available for the EVAL-AD7276SDZ :
•
VIN (J7)—for use with a unipolar signal source
•
VIN UNBIASED (J5)—for use with a bipolar signal source
VIN (J7)
Use the VIN (J7) input when a unipolar signal source is avail-
able (see Table 4 for jumper settings). The input is buffered by
U7 and fed to the AD7276 via an R-C filter.
Table 4. Unipolar Input Jumper Settings
Link Jumper Settings
LK8 Removed
All Other Links Set as described in Table 3.
VIN UNBIASED (J5)
Use the VIN UNBIASED (J5) input when a bipolar signal source is
available (see Table 5 for jumper settings). The input is biased up
by U6 and buffered by U7 and then is fed to the
AD7276 via an
R-C filter.
Table 5. Bipolar Input Jumper Settings
Link Jumper Settings
LK11 Removed
All Other Links Set as described in Table 3.
REFERENCE OPTIONS
The following on-board reference supply is available:
•
AD780 : 2.5 V/3.0 V ultrahigh precision band gap voltage ref-
erence. The reference is taken from the V
DD
pin of the AD7276 .
Alternatively, an external reference voltage can be applied to J4.
SOCKETS/CONNECTORS
Table 6. Socket/Connector Functions
Socket Function
J1 PWR. A 7 V to 9 V dc transformer power connector.
J2 A 7 V to 9 V bench supply screw terminal connector.
J3 V
SS
and V
DD
. Screw terminal connectors for external
amplifier power supplies.
J4 External power supply for V
DD
of the AD7276 .
J5 VIN UNBIASED. Analog input for use with bipolar
signal sources.
J6 CS. External connection to CS .
J7 VIN. Analog input for use with unipolar signal sources.
J8 SCLK. External connection to SCLK.
J9 SDATA. External connection to SDATA.
J10 EVAL-SDP-CB1Z evaluation board controller socket.