National Semiconductor ADC08200, Instruction Manual

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1.0 Introduction
2. Install a 200 MHz (or lower) oscillator into socket
Y1. While the oscillator may be soldered to the
board, using a socket will allow you to easily change
clock frequencies.
The ADC08200EVAL Design Kit (consisting of the
ADC08200 Evaluation Board, National Semiconductor's
WaveVision© software and this manual) is designed to
ease evaluation and design-in of Nationals ADC08200 8-
bit Analog-to-Digital Converter, which operates at sample
rates up to 230 Msps.
3. Connect a clean power supply to the terminals of
connector P1. Adjust power supply to voltages of
+4.75V to +5.25V at pins 1 and 3 and -5.2 to -5.3V
at pin 4 (ground is pin 2) before connecting it to the
board. Turn on the power and confirm that there is 3
Volts at TP7 or at the pins of inductor L1.
The WaveVision software operates under Microsoft
Windows®. The signal at the Analog Input is digitized
and can be captured and displayed on the computer
monitor as dynamic waveforms. The digitized output is
also available at Euro connector J1.
4. Use RV1 to set the top reference voltage (VRFT) for
the ADC to 1.9V ±0.05V at TP2. Use RV2 to set the
bottom reference voltage (VRFB) for the ADC to
0.3V ±0.05V at TP3.
The software can perform an FFT on the captured data
upon command. This FFT display also shows dynamic
performance in the form of SNR, SINAD, THD and
SFDR.
5. Connect the jumper at JP1 to pins 2 and 3 (those
closest to Q1) to use oscillator Y1 frequency without
dividing it by 2.
6. If they are not hard wired, connect the jumper at JP2
and JP8 to pins 2 and 3 (those closest to input BNC
J3) and the jumper at JP7 to pins 1 and 2 (those
farthest fro input BNC J3) to use both FIFOs U8 and
U10.
Evaluation with this system is simplified by connecting
the board to the WaveVision Digital Interface Board
(order number WAVEVSN BRD 3.0), which is connected
to a personal computer through a serial communication
port and running WaveVision software, operating under
Microsoft Windows. Use program WAVEVSN2.EXE,
available at National Semiconductor's web site.
7. Connect a signal of 1.6VP-P amplitude from a 50-
Ohm source to Analog Input BNC J3. The ADC
input signal can be observed at TP1. Because of
isolation resistor R32 and the scope probe
capacitance, the input signal at TP1 will not have
the same frequency response as will the ADC input
signal.
The signal at the Analog Input to the board is digitized
and is available at pins B16 through B19 and C16
through C19 of J1. Pins A16 through A21 of J1 are
ground pins.
Provision is made for adjustment of the Reference
Voltages, VRT and VRB with potentiometers VR1 and
VR2, respectively. These voltages are regulated with an
LM4040-2.5 reference.
8. The Digital Interface Board should be set up for10
MHz operation with an 80MHz oscillator installed.
See the Digital Interface Board manual.
9. See the Digital Interface Board Manual for data
gathering instructions.
2.0 Board Assembly
The ADC08200 Evaluation Board comes pre-assembled
but may be obtained as a bare board that must be
assembled. Refer to the Bill of Materials for a description
of components, to
Figure 1 for major component
placement and to Figure 2 for the Evaluation Board
schematic.
NOTE: The FFT will not indicate the correct frequencies
because this information is derived from the clock
frequency selected on the Digital Interface Board. To
show the correct frequency information on the FFT,
double click on the FFT window to open the FFT Dialog
Box, then click on "Frequency", enter the sample rate in
MHz, then click on "OK". Alternatively, you may double
click on the data capture window before performing the
FFT and change the frequency at "Sampling Rate of This
Data (MHz)" to 200 to indicate a 200 MHz sample rate.
3.0 Quick Start
Refer to Figure 1 for locations of test points and major
components.
1. Connect the evaluation board to the Digital Interface
Board (order number WAVEVSN BRD 3.0). See the
Digital Interface Board Manual for operation of that
board.
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