Sony Corporation

Akira Li

Yutaka Hayashi

Mitsuo Soneda

Akihiro Nakamura

Hideki Usuki

An input signal SIN is input to a reset input terminal R of a flip-flop RSFF1 and, at the same time, input to a gate of a pMOS transistor MP1 constituting a transfer control circuit DCNTL1, a signal Bd obtained by delaying an inverted output signal B of the flip-flop RSFF1 at a delay circuit DLY1 is input to the data input terminal of the transfer control circuit DCNTL1, and the output signal of the transfer control circuit DCNTL1 is input to a set input terminal S of the flip-flop RSFF1 via two stages of inverters connected in series, therefore, a signal change detection circuit capable of generating a stable pulse according to the level change of the input signal without depending upon the input clock signal and capable of generating the pulse at high speed can be realized.

Signal change detection circuit

An internal power supply circuit, comprising a plurality of charge accumulators, a first power supply terminal, a second power supply terminal, a first switch for connecting the plurality of charge accumulators in parallel to each other in a first state, and a second switch for connecting the plurality of charge accumulators in series with each other in a second state, the charge accumulators connected between the first power supply terminal and the second power supply terminal at either the first state or the second state, and the first state and the second state set repeatedly to raise or lower a voltage between the first power supply terminal and the second power supply terminal.

Internal power supply circuit

A semiconductor memory device wherein source lines of a memory cell array constituted by a plurality of memory cells arranged in the form of a matrix at intersecting points of word lines and bit lines are arranged in a row direction or a column direction and the source lines of the nonselected rows or the nonselected columns are inversely biased with respect to the semiconductor substrate, thereby to prevent erroneous reading by the leakage current at the time of reading data and further reduce the write current at the time of writing. Further, the read operation is kept from deteriorating by reducing the amplitude of the source line at the time of reading by setting the inverse bias voltage at a minimum constant voltage smaller than the power source voltage.

Growing community of inventors

Kanagawa, Japan

Akira Li