National Semiconductor ADC08100, Инструкция по эксплуатации

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5.2.6 Troubleshooting
If the displayed waveform appears to be garbage, or if
the FFT plot shows nothing but noise with no apparent
signal:
"Comm Check Failed", "Error Transmitting", "Parallel Port
Time Out Error" and/or "Failed to communicate with the
board on LPT1" errors mean communication was
unsuccessful. Try the following:
•
Reset the evaluation board by pressing button S1
and try again.
•
Be sure to wait for yellow LED D4 on the Digital
Interface Board to go out after turning on power
before trying to capture data.
•
Be sure clock Y1 is of the proper frequency
(100MHz) and type (ECL with output swing between
-0.6V
and
-1.3V).
•
Be sure that the Digital Interface Board is connected
to a serial printer port and has power.
•
Reset the board by pressing S1 and try again.
•
Be sure the proper port is selected (type
ALT
-O).
•
Ascertain that an 80MHz clock oscillator is properly
inserted into the socket at Y1 of the Digital Interface
Board. Check to see that LEDs D1 and D3 of the
Digital Interface Board are on. See the Digital
Interface Board manual for their functions.
Problem Opening Comm Port" or "Error Setting Comm
State" errors mean that the comm port selected is not the
one to which the eval board is connected.
6.0 Evaluation Board Specifications
•
Be sure cable connections are solid.
Board Size: 5" x 7" (12.7cm x 17.8 cm)
•
Be sure that the board to computer cable is not a
Null Modem one. If it is, swap the jumpers on Digital
Interface Board J8 and J10.
Power Requirements: + 5V ±5% @ 100 mA
+ 5V ±5% @ 750mA (see
Section 4.6)
•
Reset the evaluation board by pressing button S1
and try again.
- 5.2V.0 ±0.1V @ 250 mA
Clock Frequency Range: 40 MHz to 250 MHz
(divided by 2 for the ADC)
If there is no output from the ADC08100, perform the
following:
Analog Input
•
Be sure that the proper voltages and polarities are
present at Power Connector P1.
Nominal Voltage: 1.6VP-P
Frequency Range 50 kHz to 150 MHz
•
Be sure +3 Volts is present at TP9.
Impedance: 50 Ohms
•
Be sure clock signal is present at J4 center pin.
•
Be sure there is an input signal at TP7 and that the
signal generator and input filter are of compatible
frequencies.
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