Patent ID: 7460417
Filing Date: 2008-12-02
Classification: G11C

Abstract:
1. A semiconductor device having an interface of an open drain type or a pseudo-open drain type, the semiconductor device comprising: a data strobe (DQS) control signal generating circuit configured to generate a first DQS control signal and a second DQS control signal; a DQS control circuit configured to control a data strobe signal DQS by sequentially changing a state of a following section next to a postamble section of the data strobe signal DQS in response to a clock signal, the first DQS control signal and the second DQS control signal, sequentially from a first logical state of the postamble section to a second logical state, and from the second logical state to a high impedance state after a first predetermined time wherein the second logical state is different than the high impedance state; and an output unit configured to output the data strobe signal DQS.