Abstract: A semiconductor memory device having a self-refresh operation includes a detection circuit generating a detection signal when detecting a change of a given input signal, and a comparator circuit comparing the detection signal with a refresh request signal internally generated and generating a control signal indicative of a circuit operation.

Abstract: A semiconductor memory device having a self-refresh operation includes a first circuit generating a first signal that specifies a first self-refresh cycle by a non-volatile circuit element provided in the semiconductor memory device, a second circuit receiving a second signal that specifies a second self-refresh cycle via a terminal that is used in common to another signal, and a third circuit generating a pulse signal having one of the first and second self-refresh cycles, the pulse signal being related to the self-refresh operation.

Abstract: A semiconductor device has a normal mode and a test mode for testing the semiconductor device, and is provided with a first circuit which receives an input signal, a test signal and an output enable signal, and outputs the input signal in response to the output enable signal, a second circuit which is coupled to the first circuit and outputs the input signal obtained from the first circuit, and power supply pads which receive a power supply voltage which is supplied in common to the first circuit and the second circuit. The first circuit fixes an output impedance of the second circuit to a high-impedance regardless of the output enable signal when the test signal indicates the test mode.

Abstract: A high-speed DRAM, which comprises a plurality of separated operation circuits that perform accessing the memory cell array according to the detection of the transition of input signals and prevents a fatal malfunction even when glitches are generated in input signals, has been disclosed. The DRAM is designed so that erroneous data is not written to or read from by varying the possibility (sensitivity) with which a plurality of separated operation circuits initiate the operation according to the ATD signal.