4.5 Digital Data Output.
input to the evaluation board when evaluating sinusoidal
signals to be sure there are no unwanted frequencies
(harmonics and noise) presented to the ADC. It is
important to realize that no frequency generator or
synthesizer produces a pure enough sine wave to
evaluate an A/D Converter without the use of a good
filter. If the WaveVison4 capture board is used, a USB
cable must be connected between the WaveVision4
Capture Board and the host computer. See the
WaveVision4 Capture Board User's Guide for details.
The digital output data from the DUT is available at
Header LA1 for connection to a logic analyzer. Data is
transferred over FutureBus J5 for use with the
WaveVision4 data capture board.
4.6 Power Supply Connections
Power to this board is supplied through power connector
J6. The only Voltage needed for the evaluation board is a
5.5V to +5.7V supply.
5.1 Software Installation
When using this evaluation Board with the WaveVision4
Capture Board, the +5V logic power supply for that
Capture board and the +5V of the DUT evaluation board
are connected together through pins A1, B1, A2 and B2
of J2. Diode D1 between P1 and the WaveVision4 board
is meant to prevent the higher voltage at DUT board P1
from getting to the WaveVision4 board. Providing the
+5.5V to +5.7V to the DUT board will p5V to the
WaveVision4 board through D1 and the WaveVision4
board pins A1, B1, A2 and B2 of J2.
The WaveVision4 software provided requires about 6
Megabytes of hard drive space, including the Java files,
and runs under Windows. See the WaveVision4 Capture
Board Users' Guide for WaveVision4 software installation
instructions.
5.2 Setting up the Evaluation Board
This evaluation package was designed to be easy and
simple to use, and to provide a quick and simple way to
evaluate the DUT. The procedures given here will help
you to properly set up the board.
4.7 Power Requirements
5.2.1 Board Set-up
Refer to
Figure 1
for locations of the major components
on the board.
Voltage and current requirements for the DUT Evaluation
Board are
1.
Connect The evaluation board to a WaveVision4
Capture Board, WAVEVSN BRD 4.0.
•
Pin 1 of P1: +5.5V to 5.7V at 50 mA
•
Pin 2 of P1: Ground
2.
Connect the desired jumper to JP1, JP2, JP3 and
JP4. (See Section 4.8).
4.8 Analog Inputs
3.
Connect power to the board per requirements of
paragraph 4.7.
The evaluation board input channel is composed of
termination components and a user choice of a.c. or d.c.
signal coupling to the DUT, as well as a choice of DUT
multiplexer inputs that are connected to inputs BNC1 and
BNC2. Short together pins 1 and 2 of JP1 and JP3 to a.c.
couple the input signals. Short pins 5 and 6 of JP1 and
JP3 to d.c. couple the input signal to the DUT. Shorting
together pins 3 and 4 of JP1 or JP3 will ground the
corresponding ADC input.
4.
Connect a USB cable between the WaveVision4
Capture Board and a USB port on your computer.
5.
Connect a clean power supply to the terminals of
connector P1. Adjust power supply to a voltage of
±5.5V to ±5.7V before connecting it to the board.
Apply power to the WaveVision4 Capture Board.
6.
Connect an appropriate test signal source to
connector BNC1 and/or BNC2 of the evaluation
board through (an) appropriate filter(s).
JP2 and JP4 determine which BNC connector is
connected to which ADC input. See
Figure 2
for the
device schematic.
5.2.2 Quick Check of Analog Functions
Refer to
Figure 1
for locations of major components on
the board. If at any time the expected response is not
obtained, see section 5.2.5 on Troubleshooting.
Caution:
Be sure that the input signals to the DUT do
not go more negative than -0.3V or more than 0.3V
above the DUT power supply.
1.
Perform steps 1 through 6 of Section 5.2.1.
2.
Adjust VR1 for the desired DUT supply voltage at
TP1.
5.0 Installing and Using the ADCxx1S101
Evaluation Board
3.
Adjust VR2 for a voltage at TP6 and TP7 that are
1/2 that at TP1.
The evaluation board requires a power supply as
described in Section 4.7. An appropriate signal generator
with 50 Ohm source impedance should be connected to
the Analog Input BNC1 and/or BNC2. A bandpass filter
should be inserted between the generator output and the
4.
Apply a signal to BNC1 and scope TP6 to be sure
the input signal is present.
5.
Apply a signal to BNC2 and scope TP7 to be sure
the input signal is present.
5
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