Method for reducing output data noise of semiconductor apparatus and semiconductor apparatus implementing the same

A method for reducing output data noise of a semiconductor apparatus which includes a plurality of output buffers to output data, the method comprising the steps of:

• driving high data to a specific output buffer among the plurality of output buffers, and driving data transiting from a low level to a high level to the other output buffers;
• and
• measuring the magnitude of data noise occurring in output data of the specific output buffer, and deciding slew rates of the plurality of output buffers based on the measurement result.

A semiconductor apparatus comprising:

• a plurality of output buffers configured to be driven by a power supply voltage and a ground voltage and output received data;
• and
• a data noise measuring unit configured to measure a magnitude of data noise from output data of a specific output buffer among the plurality of output buffers, and generate a slew rate control signal to control slew rates of the plurality of output buffers based on the measurement result.