摘要:
A semiconductor device receiving a stable external power voltage includes a reduced-voltage-generation circuit which generates an internally reduced power voltage, an input circuit which operates based on the internally reduced power voltage, causing the internally reduced power voltage to fluctuate, a clock-control circuit which generates an internal clock signal, an output circuit which outputs a data signal to an exterior of the device at output timings responsive to the internal clock signal, a clock-delivery circuit which conveys the internal clock signal from the clock-control circuit to the output circuit, and operates based on the external power voltage such as to make the output timings substantially unaffected by fluctuation of the internally reduced power voltage.
摘要:
A semiconductor integrated circuit device includes a clock buffer circuit receiving a clock signal, a data buffer circuit receiving a data signal, an output circuit outputting the data signal from the data buffer circuit in accordance with the clock signal from the clock buffer circuit, and an adjustment circuit adjusting timings of the clock signal and the data signals.
摘要:
In the present invention, an external power source supplied to an integrated circuit device is divided into a first external power source for the DLL circuit and a second external power source for circuits other than the DLL circuit. According to the present invention, it is arranged that power source noise generated in the second external power source cannot be transmitted to the variable delay circuit by utilizing the first external power source preferably for the variable delay circuit of the DLL circuit and even more preferably for its delay unit. Also, preferably, it is arranged that power source noise generated in the second external power source cannot be transmitted to the phase coincidence detection unit by utilizing the first power source for the phase coincidence detection unit in the phase comparison circuit of the DLL circuit. Also, by connecting the first external earthing power source to the variable delay circuit and/or phase coincidence detection unit, the effect of power source noise from the second external earthing power source originating from the operation of circuits other than these is suppressed.
摘要:
The present invention provides an input circuit having small current consumption in a clock synchronization type semiconductor integrated circuit. The input circuit is activated by an activation signal to receive an input signal and an activation signal generating circuit generates the activation signal. The activation signal generating circuit activates intermittently the activation signal for a time shorter than a period of a clock signal and including a setup time and a hold time of the input signal in order to activate the input circuit. The input circuit is activated only for the limited time of one period of the clock signal and therefore current consumption can be reduced.
摘要:
An input conversion unit converts serial data supplied from the exterior into parallel data. Each of the converted parallel data is respectively written into a plurality of memory cell areas. An output conversion unit converts parallel data constructed by data read from each memory cell area into serial data. An operational unit is activated during a testing mode so as to logically operate on the parallel data read from each memory cell area. By writing predetermined data into each memory cell area in advance, it is confirmed by a logic operation that correct data is stored in each memory cell area. The data can be checked simultaneously for the plurality of memory cell areas so that the operation test in the memory cell areas can be carried out at high speed. Besides, serial data accepted, twice per cycle of a data strobe signal, is converted into parallel data. Each of the converted parallel data is respectively written into a first memory cell area and a second memory cell area. Parallel data read from the first and second memory cell area is logically operated in a testing mode and the operation result is output at once in synchronization with the clock signal. Accordingly, the data can be checked simultaneously for the first and the second memory cell area so that the operation test in the memory cell areas can be carried out at high speed.
摘要:
A command receiving circuit receives a command signal for determining a circuit operation, in synchronization with a clock signal and it outputs the received command signal as an internal command signal. An address switching circuit permits transmission of an address signal to an internal circuit upon receiving the command signal. The internal circuit receives the address signal before the reception of the command signal, thereby to start its operation. As a result, the internal circuit can be operated at high speed. Besides, the address switching circuit inhibits the transmission of the address signal to the internal circuit upon receiving the internal command signal or the clock signal. Therefore, even when the level of the address signal has changed after the reception of the command signal, the change does not lead to operating the internal circuit. Accordingly, the power consumption of the semiconductor integrated circuit is reduced. Meanwhile, the semiconductor integrated circuit comprises a plurality of memory cores and a bank switch for selecting the memory cores. The bank switch feeds the address signal to predetermined memory core(s) of the memory cores in accordance with the value of the address signal. Since the memory core can receive the address signal before the validation of a command, the circuit operation is performed at high speed even in the semiconductor integrated circuit including the plurality of memory cores are controlled as bank.
摘要:
A semiconductor device that includes: a memory cell array that includes non-volatile memory cells; an area that is contained in the memory cell array and stores area data; a first storage unit that holds data transferred from the memory cell array, and outputs the data; and a control circuit that selects between a primary reading mode for causing the first storage unit to hold the area data transferred from the memory cell array and to output the area data, and a secondary reading mode for causing the first storage unit to hold a plurality of pieces of divisional data formed by dividing the area data and transferred from the memory cell array and to output the divisional data.
摘要:
A refresh signal is output in response to a refresh request generated at predetermined cycles, and a refresh operation is performed. The refresh operation ends when a conflict occurs between an access request and the refresh request. Consequently, an access operation corresponding to the access request can be started earlier with a reduction in access time. The access time can be reduced further by changing the end time of the refresh operation in accordance with the timing of supply of the access request. Since a test circuit for notifying the state of the refresh operation to exterior is formed, the operation margin of the refresh operation can be evaluated in a short time. As a result, it is possible to reduce the development period of the semiconductor memory.
摘要:
A refresh signal is output in response to a refresh request generated at predetermined cycles, and a refresh operation is performed. The refresh operation ends when a conflict occurs between an access request and the refresh request. Consequently, an access operation corresponding to the access request can be started earlier with a reduction in access time. The access time can be reduced further by changing the end time of the refresh operation in accordance with the timing of supply of the access request. Since a test circuit for notifying the state of the refresh operation to exterior is formed, the operation margin of the refresh operation can be evaluated in a short time. As a result, it is possible to reduce the development period of the semiconductor memory.
摘要:
When a test instruction signal is outputted from a command decoder, a test mode decoder receives the test instruction signal and outputs a test signal. When a DQM switch circuit receives the test signal, the DQM switch circuit outputs a mask/disable signal (MASK0 or MASK1) inputted to any one of two mask/disable terminals (DQML, DQMU) as a mask/disable signal inputted from the two terminals DQML and DQMU to a write amplifier/sense buffer. Therefore, it is possible to execute a mask/disable operation for all of input and output data with one of the two mask/disable terminals.