EVAL-AD7998_15 Datasheet, PDF (7/12 Pages) Analog Devices – Evaluation Board for the 8-Channel, 10-/12-Bit ADC with I2C-Compatible Interface

MAIN WINDOW
The upper and left portion of the evaluation board window
contains a menu bar and controls. The middle-right and
bottom-right portions contain digital storage oscilloscopes
(DSOs).
Menu Bar
The menu bar (not visible in Figure 2) consists of the File and
About menus.
File Menu
Print front Panel. Prints front panel on active printer.
Save as Picture. Saves front panel as a .jpg file.
Exit. Exits the program.
About Menu
Analog.com. Opens Analog Devices Web page.
Software Version. Displays information about the current
version of the software.
Controls
The controls include control buttons, list boxes, and indicators.
Sample. Samples selected channels.
Continuous. Repeats the sampling process.
Limit. Opens window to configure limit registers (Channel 1 only).
Sweep. Starts the sweep function.
LEDs (CH1, CH2, … CH8). Selects the input channel of the
AD7997/AD7998. When more than one channel is selected, the
AD7997/AD7998 work in sequence mode.
Load Firmware. Loads the firmware to the Cypress USB device.
Temperature. Enables temperature measurements.
Potentiometer Value Selector (Pot 1/Pot 2). Changes the value
of the selected digital potentiometer.
Codes/Volts. Determines whether data is displayed in codes
or volts.
Exit. Exits the program.
Alert LED. Indicates if an alert occurred (Channel 1 only).
Ref – VDD – 5V. Selects reference voltage source (power
supply voltage or AD780).
EVAL-AD7997EBZ/AD7998EBZ
2.5V/3V. Changes the value of the external reference voltage
(AD780).
Clear Charts. Clears the charts displayed.
Autoscale On/Autoscale Off. Click this button to turn the
autoscale feature on or off.
Alert. Shows limits on the upper digital storage oscilloscope.
Channel 1/Channel 2/…/Channel 8. Selects the input channel
of the AD7797/AD7798 for the sweep function.
Digital Storage Oscilloscopes
The middle portion of the evaluation board window displays
a waveform. When samples are uploaded from the evaluation
board, they are displayed here. At the bottom left of the upper
DSO are zoom options that allow you to zoom in and out while
viewing a sample. To the left of this DSO, information about the
sample taken is displayed, such as measured values in codes and
in volts.
The lower portion of the main window displays a waveform
of the sweep function. At the bottom left of the lower DSO
are zoom options that allow you to zoom in and out while
viewing a sample. To the right of the DSO, information about
the sample taken and the value of each point of sweep function
is displayed.
Taking Samples
During the sweep function, 256 samples are taken directly
from the digital potentiometer output. The output of the digital
potentiometer is incremented by 1, from 0 to 255, and for each
increment, the AD7997/AD7998 take a sample. After the
measurement, all 256 values are displayed on the digital storage
oscilloscope in the lower portion of the main window (see
Figure 2).
To instruct the AD7997/AD7998 to take samples click either
Sample or Continuous.
• Click Sample to perform one conversion. The result is
uploaded and displayed.
• Click Continuous to start taking samples. When
Continuous is selected, other controls can be changed.
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