Analog Devices EVAL-AD7177-2SDZ, Руководство пользователя

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UG-849 EVAL-AD7177-2SDZ User Guide
Rev. 0 | Page 6 of 14
SERIAL INTERFACE
The EVAL-AD7177-2SDZ evaluation board connects via the
serial peripheral interface (SPI) to the Blackfin® ADSP-BF527
on the EVAL-SDP-CB1Z . There are four primary signals: CS,
SCLK, and DIN (all inputs), and one output from the ADC,
DOUT/RDY.
To operate the evaluation board in standalone mode, disconnect
the evaluation board from the SDP-B controller board. Use the
test points to connect the signals to an alternative digital capture
setup or the PMOD-compatible header (A7).
POWER SUPPLIES
Power the evaluation board from the ac-to-dc adapter connected
to J5, or from an external bench top supply applied to J3 or J9.
Linear LDOs generate the required voltages from the applied
input voltage (V
IN
) rail when using J3 or J5. Use J9 to bypass the
on-board regulators. An ADP7118 regulator generates the 5 V
(single supply) and 2.5 V (split supply) supplies for the AVDD1
and AVDD2 rails to the ADC; a second
ADP7118 generates
3.3 V for the IOVDD rail. The ADP7104 supplies 5 V for the
SDP-B controller board as well as 5 V for the ADM660 voltage
converter to generate −5 V to supply the ADP7182 . The ADP7182
generates the −2.5 V supply for AVSS when operating in split
supply mode. Each supply is decoupled where it enters the board
and again at each device in accordance with the schematic.
Table 3 shows the various power supply configurations available,
including split supply operation.
Table 3. Power Supply Configurations 1
Configuration Input Voltage Range Description
Single Supply
(Regulated)
7 V to 9 V The 7 V to 9 V input is regulated to 5 V for AVDD1/AVDD2 and 3.3 V for IOVDD. This also
powers the external 5 V reference. See the Single Supply (Regulated) section in the Power
Supply Configurations section.
Single Supply
(Unregulated)
7 V to 9 V, 5 V, and 3.3 V The input is unregulated and connects directly to AVDD1/AVDD2 and IOVDD from J5. The
7 V to 9 V input powers the external 5 V reference. See the Single Supply (Unregulated) section
in the Power Supply Configurations section.
Split Supply
(Regulated)
7 V to 9 V The 7 V to 9 V input is regulated to 2.5 V for AVDD1/AVDD2, −2.5 V for AVSS and 3.3 V for
IOVDD. The 7 V to 9 V input powers the external 5 V reference. See the Split Supply
(Regulated) section in the Power Supply Configurations section.
Split Supply
(Unregulated)
7 V to 9 V, ±2.5 V, and 3.3 V The input is unregulated and connects directly to AVDD1/AVDD2 and IOVDD from J5. The
7 V to 9 V input powers the external 5 V reference. See the Split Supply (Unregulated) section in
the Power Supply Configurations section.
1
Only one configuration can be used at a time.