On-die termination circuit and driving method thereof

An on-die termination circuit comprising:

• a driving control means for sequentially generating a plurality of control signals in response to a driving signal;
• a first termination resistance supply means for supplying a termination pull-up resistance in response to a first coarse code signal having a plurality of bits and a first fine code signal having a plurality of bits;
• a first code signal generating means for controlling the first coarse and fine code signals in response to the plurality of the control signals so that the termination pull-up resistance has a level which corresponds to an input resistance;
• a second termination resistance supply means for supplying a termination pull-down resistance in response to a second coarse code signal having a plurality of bits and a second fine code signal having a plurality of bits;
• and
• a second code signal generating means for controlling the second coarse and fine code signals in response to the plurality of control signals so that the termination pull-down resistance has a level which corresponds to the termination pull-up resistance.

An on-die termination circuit comprising:

• a termination resistance supply unit for supplying a termination resistance in response to a coarse code signal having a plurality of bits and a fine code signal having a plurality of bits;
• a resistance feedback unit for receiving the fine code signals and the coarse code signals and for outputting a feedback pull-down resistance;
• a coarse code generating unit for producing the coarse code signal in order that the feedback pull-down resistance has a level corresponding to a reference resistance;
• and
• a fine code generating unit for producing the fine code signal in order that the feedback pull-down resistance has a level corresponding to the reference resistance while the coarse code signal generating unit is inactivated.