Hitachi, Ltd.

Hitachi Device Engineering Co., Ltd.

Youji Idei

Hiromasa Noda

Masakazu Aoki

Osamu Nagashima

Kazuhiko Kajigaya

Kiyoo Itoh

Masashi Horiguchi

Takeshi Sakata

Hiroaki Nambu

Kazuo Kanetani

Noriyuki Homma

Kunihiko Yamaguchi

Kenichi Ohhata

Yoshiaki Sakurai

Hisayuki Higuchi

Goro Kitsukawa

Masanori Odaka

Toru Masuda

Takeshi Kusunoki

Tetsuo Ado

Katsuhiro Shimohigashi

Jun Etoh

Yoshitaka Tadaki

Katsuyuki Sato

Osamu Tsuchiya

Tohru Nakamura

Hidetoshi Iwai

Toshihiro Sekiguchi

Jun Murata

Nobuo Tamba

Makoto Saeki

Toshiro Hiramoto

Masayuki Ohayashi

Kayoko Saito

Kenichi Ohata

Takesi Kusunoki

Ken'ichi Ohata

A dynamic RAM is divided into an input circuit block responsive to an input signal supplied from an external terminal, inclusive of an operation start signal, an internal circuit block activated in response to the signal inputted from the input circuit block, and an output circuit block for outputting a signal outputted from the internal circuit block to an external terminal. A plurality of switch MOSFETs are provided in parallel form between a power line for applying an operating voltage supplied from an external terminal and an internal power line for a first circuit portion in the internal circuit block, which does not need a storage operation upon its non-operating state. Further, the switch MOSFETs are stepwise turned on in response to controls signals produced by delaying a start signal supplied through the input circuit block in turn, so as to perform the supply of each operating voltage.

Semiconductor integrated circuit device and method of activating the same

A semiconductor memory device has a column address decoder which includes first and second pre-decoders corresponding to high-order and low-order addresses, respectively, a shift register for using the output signal of the second pre-decoder as an initial value, and an output circuit for selecting either the output signal of the second pre-decoder or the output signal of the shift register in accordance with an action mode. The select signal is formed by the output signal of the first pre-decoder and the output signal through the output circuit. The shift register includes a first shift register for an even address and a second shift register for an odd address and forms two sets of continuous select signals of the bit lines, as composed of a sequential action and an interleave action, on the basis of the initial value by combining its up and down shifting actions.

Semiconductor memory device

Semiconductor integrated circuit device and method of activating same

Semiconductor memory device with improved column selecting operation

A dynamic RAM is divided into an input circuit block responsive to an input signal supplied from an external terminal, inclusive of an operation start signal, an internal circuit block activated in response to the signal inputted from the input circuit block, and an output circuit block for outputting a signal outputted from the internal circuit block to an external terminal. A plurality of switch MOSFETs are provided in parallel between a power line for applying an operating voltage supplied from an external terminal and an internal power line for a first circuit portion in the internal circuit block, which does not need a storage operation upon reaching its non-operating state. Further, the switch MOSFETs are stepwise turned on in response to controls signals produced by delaying a start signal supplied through the input circuit block in turn, so as to perform the supply of each operating voltage.

A semiconductor memory device is provided which includes a memory cell array, a read circuit which reads data from said memory cell array, and an external terminal which receives an external clock signal. A first input circuit receives the external clock signal and outputs a first internal clock signal delayed from the external clock signal. A second input circuit receives the first internal clock signal and outputs a second internal clock signal delayed from the first internal clock signal. The memory device also includes a circuit which counts a clock signal having a frequency higher than that of the external clock signal and a circuit which starts the counting in response to the second internal clock signal, reverses the direction of said counting in response to the first internal clock signal and detects when a count of said counting circuit again reaches the count at the start of said counting, thereby outputting a timing signal therefrom. A clock output circuit is provided which outputs a third internal clock signal for controlling the operation of said read circuit based on the timing signal.

Semiconductor memory device including a clocking circuit for controlling

A clock signal received from an external terminal through an input buffer is delayed by delay circuits. A counter circuit is started up in accordance with the clock signal transmitted through the delay circuits to count an oscillation pulse having a frequency which is sufficiently high with respect to that of the clock signal. Further, the counter circuit reversely counts the count in response to a clock signal delayed by one cycle, which has passed through the input buffer. When its count once again reaches the counter value at the start of counting, the counter circuit generates an output timing signal and transmits it to an internal circuit through a clock driver. A delay time outputted from the delay circuits is set to a delay time corresponding to the sum of a delay time of the input buffer and a delay time of the clock driver.

Signal generator with synchronous mirror delay circuit

A period pulse corresponding to the shortest information retention time of those of dynamic memory cells is counted to form a refresh address to be assigned to a plurality of word lines. A carry signal outputted from the refresh address counter is divided by a divider. For each of said plurality of word lines assigned with the refresh address, one of a short period corresponding to an output pulse of a timer or a long period corresponding to the divided pulse from the divider is stored in a storage circuit as refresh time setting information. A memory cell refresh operation to be performed by the refresh address is made valid or invalid for each word line according to the refresh time setting information stored in the storage circuit and the refresh time setting information itself is made invalid by the output pulse of the divider.

Dynamic memory device, a memory module, and a method of refreshing a

Disclosed is a static type memory cell with high immunity from alpha ray-induced soft errors. The memory cell has a coupling capacitance C.sub.c between two data storage nodes 1 and 2. The p-well (or p-substrate) in which the driver-MOS transistors MN3, MN4 and the transfer MOS transistors MN1, MN2 are formed is connected to a V.sub.bb generator. The voltage V.sub.bb is set lower than the low level V.sub.L of the memory cell signal potential. Even when the potential variation .DELTA.V.sub.L of the low-voltage side node 2 is large, the parasitic diode present between the n-type diffusion layer corresponding to the source or drain of MN1-MN4 and the p-well (or p-substrate) does not turn on. Erroneous operations can therefore be prevented.

Memory cell and a memory device having reduced soft error

A decoder formed of multiple circuit blocks each including bipolar transistors Q1 and Q2 having their collectors connected to resistors R1 and R2, respectively, a bipolar transistor Q3 having its collector supplied with a power voltage, and a current source I1 connected commonly to the emitters of Q1-Q3. This circuit configuration permits the decoder and BiCMOS memories using it to operate with a low supply voltage.

Decoder and driver for use in a semiconductor memory

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Asaka, Japan

Youji Idei