Output driver circuit, output driver system and semiconductor memory device

摘要

The output driver circuit includes a plurality of pull-up sub-drivers that pull up a voltage at the output terminal according to a pull-up signal based on the output data. The output driver circuit includes a plurality of pull-down sub-drivers that pull down the voltage at the output terminal according to a pull-down signal based on the output data. Selection from among the pull-up sub-drivers is made by an assigned pull-up calibration signal and selection from among the pull-down sub-drivers by an assigned pull-down calibration signal so as to make a pull-up current drivability and a pull-down current drivability for the voltage at the output terminal equal. A timing of turning on of the pull-up sub-drivers is calibrated by the pull-down calibration signal. A timing of turning on of the pull-down sub-drivers is calibrated by the pull-up calibration signal.

主权项

1. An output driver circuit that outputs, at an output terminal, a data signal responsive to output data read from a memory core, the output driver circuit comprising:
a plurality of pull-up sub-drivers that pull up a voltage at the output terminal according to a pull-up signal based on the output data; and a plurality of pull-down sub-drivers that pull down the voltage at the output terminal according to a pull-down signal based on the output data, wherein selection from among the pull-up sub-drivers is made by an assigned pull-up calibration signal and selection from among the pull-down sub-drivers by an assigned pull-down calibration signal so as to make a pull-up current drivability and a pull-down current drivability for the voltage at the output terminal equal to each other, a timing of turning on of the pull-up sub-drivers is calibrated by the pull-down calibration signal, and a timing of turning on of the pull-down sub-drivers is calibrated by the pull-up calibration signal.