| 摘要 |
<p>An impedance calibration circuit comprises: a first calibrated voltage driving unit which is driven in response to a first enable signal and drives a first calibrated voltage by comparing the first calibrated voltage connected to external resistors and a first standard voltage; a first control code generator which is driven in response to a second enable signal and generates a first control code by comparing the first calibrated voltage and a first target voltage; and a first standard voltage generator which generates a level-adjustable first standard voltage in response to the first control code. [Reference numerals] (122) First counter; (123) First pull-up driving unit; (13) First control code generator; (14) First reference voltage generator; (151) Second pull-up driving unit; (153) Second counter; (154) Pull-down driving unit; (16) Second control code generator; (17) Second reference voltage generator</p> |
