| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an impedance matching circuit of a semiconductor element that carries out ZQ calibration with an initial value reflecting offset errors caused by changes occurred during the semiconductor process. <P>SOLUTION: The impedance matching circuit of this invention includes: a first pull-down resistor to pull down a first node so that an initial pull-down code is set; a first pull-up resistor to pull up the first node so that the pull-up calibration or an initial pull-up code is set; and a code generator to generate a pull-down code and pull-up code by using as initial values the initial pull-down code and initial pull-up code that are determined by the dummy pull-down resistor and first pull-up resistor. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
