UG-490 datasheet(13/28 Pages) AD

13 / 28 page

Evaluation Board User Guide

EVAL-AD7960FMCZ

Rev. 0 | Page 13 of 28

DC TESTING—HISTOGRAM

The histogram is most often used for dc testing where a user

tests the ADC for the code distribution for dc input and

computes the mean and standard deviation, or transition noise,

of the converter, and displays the results. Raw data is captured

and passed to the PC for statistical computations.

To perform a histogram test,

1. Select the Histogram tab.

2. Click Single Capture or Continuous Capture.

Note that a histogram test can be performed without an

external source since the evaluation board has a buffered VREF/2

source at the ADC input.

To test other dc values, apply a source to the J1/J2 inputs. You

may be required to filter the signal to make the dc source noise

compatible with that of the ADC.

AC TESTING—HISTOGRAM

Figure 21 shows the Histogram tab. This tests the ADC for

the code distribution for ac input and computes the mean and

standard deviation, or transition noise, of the converter and

displays the results. Raw data is captured and passed to the PC

for statistical computations.

To perform a histogram test,

1. Select the Histogram tab.

2. Click Single Capture or Continuous Capture.

Note that an ac histogram needs a quality signal source applied

to the input J1/J2 connectors.

Figure 21 shows the histogram for a 1 kHz sine wave applied to

the ADC input and the results calculated.

The Histogram Analysis (Label 1) illustrates the various

measured values for the data captured.

Figure 21. Histogram Capture Tab

UG-490 Datasheet(PDF) 13 Page - Analog Devices