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Input signals can also be amplified using an onboard
LMH6517 DVGA (U601). To use the DVGA, some
components must be installed and some removed. The
following components must be installed: R651-R656. The
following components must be removed: R302, R303,
R309, and R310. Then connect signals from a 50-Ohm
source to connectors J601 and J607.
4.2 ADC reference circuitry
The ADC10DV200 can use an internal or external voltage
reference. The internal reference is selectable between a
0.75V or 0.5V reference. External references can be set
from 0.2V to 1.4V. This Evaluation Board is configured to
use the internal 0.75V reference.
4.3 ADC clock circuit
Components can be installed or removed to select the
path of the clock to the ADC. While not as convenient as
pin-type jumpers, these introduce less distortion into the
clock signal.
Care must be taken to provide a high quality low jitter
clock source. A single ended input clock can be buffered
by U203 (NC7SV125) and applied to the ADC’s clock
input pin. Or U203 can be bypassed and the input clock
pin driven directly.
A differential clock can also be applied to the ADC’s clock
input pins through U201 (ETC-1-13).
Refer to Appendix A to configure the clock for your
application. The Evaluation Board is configured by default
to use a single ended clock to drive the input pins directly.
4.4 Digital Data Output
The LVDS digital output data is available for probing at
test points TP601 through TP624. The signals are also
available at the WaveVision™ (WV5) connector J602.
4.5 Data Format/ Duty Cycle Stabilizer
Output data format and the duty cycle stabilizer (DCS)
are controlled by jumper J401.
Shorting pins 1-2 of J401 sets the output format to offset
binary with DCS On. This is the default setting.
Shorting pins 3-4 of J401 sets the output format to 2’s
complement with DCS Off.
Shorting pins 5-6 of J401 sets the output format to offset
binary with DCS Off.
Shorting pins 7-8 of J401 sets the output format to 2’s
complement with DCS On.
4.6 Power Supply Connections
Power to this board is supplied through power connector
J507. The only supply needed is +5V at pin 2 plus ground
at pin 1.
Voltage and current requirements for the ADC10DV200
Evaluation Board are:

+5.0V at 500 mA
5.0 Installing the ADC10DV200 Evaluation Board
The evaluation board requires power supplies as
described in
Section 4.6 . An appropriate signal source
should be connected to the Signal Input SMA connectors
J301 or J302. When evaluating dynamic performance, an
appropriate signal generator (such as the HP8644B or the
R&S SME-03) with 50 Ohm source impedance should be
connected to the Analog Input connector through an
appropriate bandpass filter as even the best signal
generator available can not produce a signal pure enough
to evaluate the dynamic performance of an ADC.
If this board is used in conjunction with the
WaveVision5™ Data Capture Board and WaveVision5™
software, a USB must be connected between the Data
Capture Board Board and the host. See the
WaveVision5™ Data Capture Board manual for details.