| 摘要 |
PURPOSE: An impedance adjusting device is provided to increase the accuracy of a termination operation and a calibration operation without increasing the number of a bit in an impedance code. CONSTITUTION: In an impedance adjusting device, a comparison unit(410) compares the voltage of a calibration node with a reference voltage. A counter(420) counts an impedance code. A reference impedance unit(430) has an impedance value which is determined by the impedance code. The reference impedance unit is connected to the calibration node. A storage(440) stores the comparison result of the comparison unit. A termination unit terminates the interface node by a plurality of parallel resistors which is on/off in response to the impedance code. The parallel resistor is turned on/off in response to a storage signal.
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