摘要:
A module includes a semiconductor device, a phase adjustment circuit generating a second clock so that a phase adjustment signal output from the semiconductor device and a first clock have a predetermined phase relationship, and an output circuit that is provided in the semiconductor device and generates the phase adjustment signal from the second clock.
摘要:
According to the present invention, a memory circuit requiring refresh operations a first circuit which receives a command in synchronization with a clock signal, and which generates a first internal command internally and a second circuit which generates a second internal command, e.g., a refresh command, internally in a prescribed refresh cycle. And an internal circuit, according to said first internal command, executes corresponding control through clock-synchronous operations, and when said refresh command is issued, sequentially executes control corresponding to the refresh command and control corresponding to said first internal command through clock-asynchronous operations. According to the present invention, when a refresh timing signal is generated, the refresh operation can be intrupted among the external command operations.
摘要:
According to the present invention, a memory circuit requiring refresh operations a first circuit which receives a command in synchronization with a clock signal, and which generates a first internal command internally and a second circuit which generates a second internal command, e.g., a refresh command, internally in a prescribed refresh cycle. And an internal circuit, according to said first internal command, executes corresponding control through clock-synchronous operations, and when said refresh command is issued, sequentially executes control corresponding to the refresh command and control corresponding to said first internal command through clock-asynchronous operations. According to the present invention, when a refresh timing signal is generated, the refresh operation can be interrupted among the external command operations.
摘要:
Flags are formed to respectively correspond to memory cell groups each including volatile memory cells. Each flag indicates as a set state that the memory cells store data in a second memory mode. In a changing operation of changing from a first memory mode in which data is independently retained by each memory cell to a second memory mode in which same data are retained in the memory cells of each memory cell group, each flag is reset in response to the first access to the corresponding memory cell group. Therefore, only the first access is made in the second memory mode in each memory cell group. The memory cells are accessed in a mode according to the flag in the changing operation, thereby allowing a system managing the semiconductor memory to freely access the memory cells even during the changing operation. Consequently, a practical changing time can be eliminated.
摘要:
A semiconductor memory device includes a plurality of N external ports, each of which receives commands, and an internal circuit which performs at least N access operations during a minimum interval of the commands that are input into one of the external ports.
摘要:
An input circuit has an input buffer and a detection circuit. The input buffer receives an external signal and outputs an internal signal. The detection circuit detects whether or not the external signal is provided. The input buffer outputs the internal signal when an output of the detection circuit indicates that the external signal is provided. This arrangement shortens the lock-on time of an internal circuit (synchronous circuit).
摘要:
According to the present invention, a memory circuit requiring refresh operations a first circuit which receives a command in synchronization with a clock signal, and which generates a first internal command internally and a second circuit which generates a second internal command, i.g. a refresh command, internally in a prescribed refresh cycle. And an internal circuit, according to said first internal command, executes corresponding control through clock-synchronous operations, and when said refresh command is issued, sequentially executes control corresponding to the refresh command and control corresponding to said first internal command through clock-asynchronous operations. According to the present invention, when a refresh timing signal is generated, the refresh operation can be intrupted among the external command operations.
摘要:
Disclosed is a semiconductor device for outputting an output signal with a given phase held relative to an external clock despite a difference in characteristic, a change in temperature, and a fluctuation in supply voltage. The semiconductor device comprises an input circuit for inputting the external clock and outputting a reference signal, an output circuit for receiving an output timing signal and outputting an output signal according to the timing of the output timing signal, and an output timing control circuit for controlling the output timing so that the output signal exhibits a given phase relative to the external clock. The output timing control circuit includes a delay circuit for delaying the reference signal by a specified magnitude and generating an output timing signal, a phase comparison circuit for comparing the phase of the output timing signal with the phase of the reference signal, and a delay control circuit for specifying the magnitude of a delay to be produced by the delay circuit according to the result of comparison performed by the phase comparison circuit.
摘要:
Disclosed is a semiconductor device for outputting an output signal with a given phase held relative to an external clock despite a difference in characteristic, a change in temperature, and a fluctuation in supply voltage. The semiconductor device comprises an input circuit for inputting the external clock and outputting a reference signal, an output circuit for receiving an output timing signal and outputting an output signal according to the timing of the output timing signal, and an output timing control circuit for controlling the output timing so that the output signal exhibits a given phase relative to the external clock. The output timing control circuit includes a delay circuit for delaying the reference signal by a specified magnitude and generating an output timing signal, a phase comparison circuit for comparing the phase of the output timing signal with the phase of the reference signal, and a delay control circuit for specifying the magnitude of a delay to be produced by the delay circuit according to the result of comparison performed by the phase comparison circuit.
摘要:
A semiconductor memory includes memory cell blocks, a burst-length information generating circuit which generates burst-length information based on a burst length, and a block enable circuit which receives the burst-length information. The block enable circuit selectively enables one of the memory cell blocks when the burst length is equal to or shorter than a predetermined burst length and selectively enables a plurality of memory cell blocks based on the burst length when the burst length is longer than the predetermined burst length. Data are read from the above-mentioned one or plurality of memory cell blocks.