Fujitsu Corporation

Fujitsu Vlsi Limited

Hirohiko Mochizuki

Yoshihiro Takemae

Yukinori Kodama

Atsushi Hatakeyama

Masao Taguchi

Masao Nakano

Makoto Yanagisawa

Takaaki Suzuki

Fumio Baba

Tsuyoshi Ohira

Junji Ogawa

Hiroyoshi Tomita

Tadao Aikawa

Hidenori Nomura

Hideaki Kawai

Yasurou Matsuzaki

Tomio Nakano

Shusaku Yamaguchi

Hatsuo Miyahara

Yoshinori Okajima

Masato Takita

Yasuhiro Fujii

Tetsuya Endo

Shinya Fujioka

Koichi Nishimura

Takaaki Furuyama

Kimiaki Sato

Eiichi Nagai

Akira Sugiura

Yukihiro Nomura

Toyonobu Yamada

Katsumi Shigenobu

Tomoharu Oka

Meiko Kobayashi

A semiconductor device includes a one-shot pulse generating circuit that generates a one-shot pulse having a predetermined pulse width at a rise or fall timing of a first clock signal, a cycle time measuring circuit that measures a cycle-time of the first clock signal from the one-shot pulse output from the one-shot pulse generating circuit, an internal clock generating circuit that generates a second clock signal based on the cycle time measured by the cycle time measuring circuit and the one-shot pulse output from the one-shot pulse generating circuit. The second clock signal has a cycle time identical to the first clock signal and has a rise or fall timing which is advanced by a specific time than that of the first clock signal, and the specific time is obtained by subtracting the cycle time of the first clock signal from a predetermined time, and a data output circuit that outputs data after a predetermined delay time from the rise or fall timing of the second clock signal.

Semiconductor device

A semiconductor memory device includes memory cells, word lines connected to the memory cells, bit lines connected to the memory cells, and a first circuit which resets the bit lines to a reset potential which is based on data read in a previous read cycle.

Semiconductor memory device having a dummy cell resetting the bit lines

A system and a semiconductor device for realizing such a system are disclosed. The system uses at least a semiconductor device for retrieving an input signal in synchronism with an internal clock generated from an external clock, the input signal remaining effectively in synchronism with the external clock. Even in the case where a phase difference develops between a clock and a signal at the receiving end, or even in the case where a phase difference develops between a clock input circuit and other signal input circuits in the semiconductor device at the receiving end, data can be transferred at high speed. Each input circuit of the semiconductor device at the receiving end includes an input timing adjusting circuit for adjusting the phase of the clock applied to the input circuit in such a manner that the input circuit retrieves the input signal in an effective and stable state. In the case where the skew between the input signals is small as compared with the skew between the input signals and the clock, an input timing adjusting circuit is shared by a plurality of the input circuits.

System configured of synchronous semiconductor device for adjusting

A semiconductor device includes a one-shot pulse generating circuit that generates a one-shot pulse having a predetermined pulse width at a rise or fall timing of a first clock signal, a cycle time measuring circuit that measures a cycle time of the first clock signal from the one-shot pulse output from the one-shot pulse generating circuit, an internal clock generating circuit that generates a second clock signal based on the cycle time measured by the cycle time measuring circuit and the one-shot pulse output from the one-shot pulse generating circuit. The second clock signal has a cycle time identical to the first clock signal and has a rise or fall timing which is advanced by a specific time than that of the first clock signal, and the specific time is obtained by subtracting the cycle time of the first clock signal from a predetermined time, and a data output circuit that outputs data after a predetermined delay time from the rise or fall timing of the second clock signal.

A semiconductor integrated circuit device includes a reference voltage generating circuit outputting a reference voltage from a step-up voltage, a step-up circuit stepping up the reference voltage within a range lower than an external power supply voltage and thus outputting the above step-up voltage, a step-down circuit stepping down the external power supply voltage and thus outputting a step-down voltage equal to the reference voltage, and an internal circuit receiving, as a power supply voltage thereof, the step-down voltage.

Semiconductor integrated circuit device with voltage patterns

A semiconductor memory device uses a wave pipeline system which can reduce a power consumption by reducing a current for charging a data bus between a memory core part and an output circuit. A single line data bus transmits read data output from the memory core part. A data bus drive circuit outputs the read read data to send to the single data bus. Each of a plurality of data latch circuits has a data input terminal connected to the data bus. A data input control circuit inputs the read data which is serially transmitted on the data bus to the data latch circuits in parallel in response to an operation of the data bus drive circuit. A data output control circuit outputs the latched read data in an order of latching by sequentially selecting outputs of the data latch circuits.

Semiconductor memory device having a single line data bus and latch

A semiconductor or memory device has a decoder circuit for decoding a plurality of external address signals. The external address signals include first and second external address signals. A first address buffer receives the first external address signals and outputs first internal address signals to first address lines. A second address buffer receives the second external address signals and outputs second internal address signals to second address lines. First predecoders have input terminals connected to the first address lines, and output first predecode signals to first predecode lines. Second predecoders have input terminals connected to the second address lines and output second predecode signals to second predecode lines. Main decoders have input terminals connected to the first predecode lines and the second predecode lines and output decode signals. The number of the first external address signals are greater than the number of the second external address signals. The second predecoders and the second predecode lines are provided at least in double in such a manner that inputs of the main decoders to be connected to each of the second predecode lines are equal in number to inputs of the main decoders to be connected to each of the first predecode lines. It is possible to shorten the transition time of predecode signals because of the same capacitive load of the predecoder circuit.

Decoder circuit for a semiconductor memory device

A semiconductor integrated circuit system includes a first power line which supplies a first source power voltage, and a second power line which supplies a second source power voltage. A first edge detecting unit outputs a first edge detection signal when a rising edge of the first source power voltage is detected. A second edge detecting unit outputs a second edge detection signal when a rising edge of the second source power voltage is detected. An output unit is connected to the first power line, and outputs data to a data terminal in a data output cycle and sets the data terminal in a high-impedance state in response to the first edge detection signal. An output control unit is connected to the second power line, and controls the output unit in accordance with a read-data signal in the data output cycle, and controls the output unit in response to the second edge detection signal, so that the data terminal is set in the high-impedance state by the output unit.

Semiconductor integrated circuit system

A data transfer apparatus is disclosed which has a first, a second, and a third pipeline processing circuits disposed in cascade connection. The first and the second pipeline processing circuits are each provided with an arbitrary signal processing circuit, a switch element for controlling the introduction of data into the signal processing circuit, and a switch control circuit for turning on the switch element on detecting completion of the transfer of data from the signal processing circuit to a pipeline processing circuit in the subsequent stage. The third pipeline processing circuit is provided with an output circuit and a switch element for introducing data transferred from the second pipeline processing circuit into the output circuit as synchronized with an external clock signal. Between the first and the second pipeline processing circuit, therefore, data can be transferred with a timing conforming to the timing of the operation of the signal processing circuit without being synchronized with an external clock signal. In the output circuit, data can be issued as synchronized with an external clock signal. Thus, a signal of a very high frequency can be selected as a clock signal for setting the timing of the whole of a system incorporating the data transfer apparatus therein.

Apparatus for data transfer capable of pipeline processing by cascading

A semiconductor device includes a one-shot pulse generating circuit that generates a one-shot pulse having a predetermined pulse width at a rise or fall timing of a first clock signal, a cycle time measuring circuit that measures a cycle time of the first clock signal from the one-shot pulse output from the one-shot pulse generating circuit, an internal clock generating circuit that generates a second clock signal based on the cycle time measured by the cycle time measuring circuit and the one-shot pulse output from the one-shot pulse generating circuit. The second clock signal has a cycle time identical to the first clock signal and has rise or fall timing which is advanced by a specific time than that of the first clock signal, and the specific time is obtained by subtracting the cycle time of the first clock signal from a predetermined time, and a data output circuit that outputs data after a predetermined delay time from the rise or fall timing of the second clock signal.

Reference voltage generating circuit having step-down circuit outputting

A semiconductor memory has a plurality of memory arrays, and a plurality of selection circuits. Each of the memory arrays has a plurality of memory blocks. The selection circuits is provided to the memory arrays and is used to independently disable a defective memory block and select a normal memory block in the memory array. Therefore, the semiconductor memory enables to increase the number of partial good memories (half good memories: half capacity memory), and to increase a product yield.

Semiconductor memory for increasing the number of half good memories by

A semiconductor circuit has a first transistor, a second transistor, a third transistor, and a fourth transistor. The first and fourth transistors are a first conduction type, and the second and third transistors are a second conduction type opposite to the first conduction type. The semiconductor circuit employs a first power supply line for supplying a first voltage, a second power supply line for supplying a second voltage, and a third power supply line for supplying a third voltage outside of the range determined by the first voltage and the second voltage. The first, second, and third transistors are connected in series between the second power supply line and the third power supply line, and the fourth transistor is connected between an input terminal and a control electrode of the first transistor.

Growing community of inventors

Kawasaki, Japan

Hirohiko Mochizuki