Source driver performing eye margin test for signal quality visualization and operating method thereof

A source driver comprising:

• an interface circuit configured to
• generate equalization processing data by equalizing data,
• generate a normal data signal based on the equalization processing data, and
• generate eye margin test result data by sampling the equalization processing data at a reference timing interval based on an eye margin test signal at an enable level;
• and
• a display driving circuit configured to generate a data signal corresponding to the eye margin test result data.

A method of driving a display device comprising:

• receiving an eye margin test signal from a timing controller, the eye margin test signal instructing a test of data and eye margin;
• performing an eye margin test on the data to generate eye margin test result data;
• generating an eye diagram data signal including grayscale information for displaying an eye diagram based on the eye margin test result data;
• and
• applying a data signal corresponding to the eye diagram data signal to a plurality of pixels.