EVAL-AD7795 Datasheet, PDF (9/16 Pages) Analog Devices – Evaluation Board for the AD7795 16-Bit, Low Power Sigma-Delta ADC (6 Channels)

TEMP DEMO
To access the temperature demonstration window, click the Temp
Demo button. The AD7795 evaluation board has a temperature
demonstration included on the board. To operate the temperature
demonstration, LK2 to LK6 should be inserted and LK1 should
be removed. With these links in place, the AD7795 excitation
current is connected to a 1 kΩ thermistor, which is connected
across the AIN4(+)/AIN4(−) pins. In series with the thermistor
is a 5 kΩ precision resistor that is used to generate the reference
voltage. The ratiometric configuration optimizes the system perfor-
mance. The temperature demonstration software saves the values
in the mode register, the configuration register, and the IO register.
EVAL-AD7795
The software then configures the AD7795 to operate with a
210 μA excitation current, the AIN4(+)/AIN4(−) channel is
selected as the analog input, the gain is set to 1, and the external
reference REFIN1(+)/REFIN1(−) is selected. When the Run
button is clicked, the software continuously reads the conver-
sion from the AIN4(+)/AIN4(−) channel and converts the
result to temperature using a lookup table.
When Run is clicked again, the temperature demonstration
execution is halted. To exit the temperature demonstration,
click the Back button. The software sets the configuration
register, the mode register, and the I/O register to their pre-
temperature demonstration values.
Figure 6. AD7795 Temperature Demo Window
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