National Semiconductor ADC08200, Инструкция по эксплуатации, Страница: 7 / 16

Note that the divide by 2 function (JP1) does not function.
A lower clock frequency requires the use of a lower
frequency oscillator.
5.0 Installing and Using the ADC08200
Evaluation Board
The evaluation board requires power supplies as
described in Section 4.6. An appropriate signal source
(such as the HP3325B, HP8662A or the Tektronix
TSG130A) with 50 Ohm source impedance should be
connected to the Analog Input BNC J3. The generator
output should be filtered by a bandpass filter when
evaluating sinusoidal signals to be sure there are no
unwanted frequencies (harmonics and noise) presented
to the ADC. A cable with a DB-9 connector must be
connected between the Digital Interface Board and the
host computer. See the Digital Interface Board manual
for details.
An ECL-level crystal oscillator may be installed at Y1, or
the desired frequency may be applied to pin 8 of the Y1
socket. The signal level should be ECL levels.
Caution: Be sure that the oscillator used has the above
suggested levels. We have found oscillators with levels
outside of this range will not work properly in the circuit
designed for this board.
R31 and C11 are used for high frequency termination
of the clock line. An 80MHz clock oscillator should be
used on the Digital Interface Board with that board's
clock divider set for 4. See the Digital Interface Board
manual for details on setting the clock divider.
5.1 Software Installation
The WaveVision software provided requires 300k bytes
of hard drive space and will run under Windows.
Note that the reported sample rate is the rate at which
the FIFO is read, so it is necessary to manually change
this by double clicking on the data window after each
data capture and changing the sample rate to that
actually used.
1. Insert the disk into a 3.5" floppy drive.
2. Copy the program WAVEVSN2.EXE to the desired
subdirectory on you computer's hard disk and
RUN
it.
Alternatively, you may download the shoftware from
national Semiconductor's ADC web site.
4.4 Digital Data Output.
5.2 Setting up the ADC08200 Evaluation Board
The digital output data from the ADC08200 is available at
the 96-pin Euro connector J1. The series resistors of R35
isolate the ADC from the load circuit to reduce noise
coupling into the ADC.
This evaluation package was designed to be easy and
simple to use, and to provide a quick and simple way to
evaluate the ADC08200. The procedures given here will
help you to properly set up the board.
4.5 Power Supply Connections
5.2.1 Board Set-up
Refer to Figure 1 for locations of connectors, test points
and jumpers on the board.
Power to this board is supplied through power connector
J4. The ADC08200 evaluation board re5V at pins
1 and 3 and -5.2V at pin 4. Pin 2 is ground.
5.2.1.1 Computer Mode Operation
1. Be sure a 200MHz clock oscillator (Y1) is in place
on the ADC08200 evaluation board and an 80MHz
oscillator is on the Digital Interface board.
When using the ADC08200 Evaluation Board with the
Digital Interface Board, the 5V logic power supply for the
interface board is passed through the ADC08200
evaluation board from pin 3 of Power Connector J4. The
supply voltages are protected by shunt diodes D1, D2
and D4. The +3 Volts needed for the ADC08200 is
provided with voltage regulator U7, an LM317T.
2. Set jumper JP1 to its default position, as shown in
Figure 1
so that the clock oscillator frequency is
NOT divided by two for the ADC08200.
3. Connect The ADC08200 evaluation board to Digital
Interface Board, WAVEVSN BRD 3.0.
4.6 Power Requirements
4. Connect a cable with DB-9 connector between the
Digital Interface Board connector P1 and a serial
port on your computer.
Voltage and current requirements for the ADC08200
Evaluation Board are:
5. Connect power to the board per requirements of
section 4.6.
•
Pin 1 of P1: +5.0V ±5% at 3 mA
•
Pin 3 of P1: +5.0V ±5% at 1.0 A.
6. Connect an appropriate signal source to BNC
connector J3 of the ADC08200 evaluation board.
Rebember to use an appropriate filter, as discussed
in sections 4.1 and 5.0.
•
Pin 4 of P1: - 5.2V to -5.3V at 250 mA.
Pin 2 of J4 is ground. The +5V supply at pin 3 of the
Power Connector P1 provides the power to the Digital
Interface Board, where most of the power through this pin
is consumed.
7. Capture data by clicking on the sine wave icon of
the WaveVision software, or press
CTRL
-X on the
keyboard.
5.2.1.2 Manual Mode Operation
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