Digital circuit, LSI including the same and method for removing noise

A method for removing noise, comprising the steps of:

• a) generating a raw clock signal synchronized with a first clock signal from the first clock signal;
• b) synchronizing the raw clock signal with a second clock signal;
• and
• c) synchronizing the signal obtained by the step b) with the first clock signal, thereby generating a reproduced clock signal.

A digital circuit comprising:

• a clock generator which receives a first clock signal and generates a raw clock signal synchronized with the first clock signal;
• a first circuit section which outputs the raw clock signal synchronously with a second clock signal;
• and
• a second circuit section which outputs, as a reproduced clock signal, the output signal from the first circuit section synchronously with the first clock signal;
• a differentiator circuit section which receives said second clock signal as a clock signal and said raw clock signal as a data signal, said differentiator outputs a third clock signal;
• a first counter which operates synchronously with said first clock signal and which counts a number of pulses of said reproduced clock signal;
• and
• a second counter which operates synchronously with said second clock signal and which counts a number of pulses of said third clock signal.