摘要:
A semiconductor memory device includes a plurality of memory blocks formed of a flash memory. The semiconductor memory device further includes a rewriting monitor circuit for memorizing the number of times of data rewriting in each of the memory blocks, and a switching circuit for switching a memory block selection address. When the number of times of rewriting in a first memory block which is a rewriting request object exceeds a predetermined value, data in a second memory block is transferred to the first memory block. Data to be written is written to the second memory block. Therefore, it is possible to increase the number of times of rewriting in the flash memory.
摘要:
Disclosed is a regulator including: a differential amplifier having a differential input stage receiving a reference voltage and an output terminal voltage, a push-pull type output portion of a current mirror configuration, a drive transistor having a control terminal connected to an output portion of the differential amplifier, first and second transistors cascode-connected between a control terminal of the drive transistor and a power supply, and third and fourth transistors cascode-connected between the control terminal of the drive transistor and ground. Control terminals of the first and the third transistors are respectively connected to control terminals of the push-pull transistors, control terminals of the second and fourth transistors are respectively connected to a first and a second control signal. A voltage of the control terminal of the drive transistor is controlled, based on the first and the second control signals, by output of the differential amplifier and the first transistor, or by output of the differential amplifier and the third transistor.
摘要:
A semiconductor storage device for driving a word line by a voltage higher than an external supply voltage that includes a boost circuit for outputting a boosted voltage of a first electric potential by boosting the external power supply potential, an auxiliary capacitor for storing the output potential of the boost circuit at the time of a standby state, a switch for supplying to a word line driving power supply line a second electric potential obtained by voltage dividing the first electric potential at the time of the standby and being turned off at the time of an operation, and an amplifier circuit for receiving the first electric potential as a driving power supply potential and driving the word line driving power supply line by the second electric potential at the time of the operation.
摘要:
A non-volatile flash memory (100) that may have an improved layout freedom is disclosed. Non-volatile flash memory (100) may include banks (B0 and B1). Each bank (B0 and B1) may include memory cell arrays (MCA00 to MCA03) including a plurality of memory cells (MC) connected to sub bit lines (LB). A plurality of sub bit lines (LB) may be selectively connected to a main bit line (MB) by a group switch (Y1S0 and Y1S1). A group of main bit lines (MB) may be disposed over a memory cell array. A group of main bit lines (MB) may be selectively connected to a sense amplifier block (SAB) by a group switch group (Y2S0 and Y2S1) and a bank switch group (Y3S0 and Y3S1). In this way, a sense amplifier block (SAB) may be shared by a plurality of groups of main bit lines (MB). In this way, layout freedom may be improved.
摘要:
Disclosed is a regulator including: a differential amplifier having a differential input stage receiving a reference voltage and an output terminal voltage, a push-pull type output portion of a current mirror configuration, a drive transistor having a control terminal connected to an output portion of the differential amplifier, first and second transistors cascode-connected between a control terminal of the drive transistor and a power supply, and third and fourth transistors cascode-connected between the control terminal of the drive transistor and ground. Control terminals of the first and the third transistors are respectively connected to control terminals of the push-pull transistors, control terminals of the second and fourth transistors are respectively connected to a first and a second control signal. A voltage of the control terminal of the drive transistor is controlled, based on the first and the second control signals, by output of the differential amplifier and the first transistor, or by output of the differential amplifier and the third transistor.
摘要:
A semiconductor memory device includes a plurality of memory blocks formed of a flash memory. The semiconductor memory device further includes a rewriting monitor circuit for memorizing the number of times of data rewriting in each of the memory blocks, and a switching circuit for switching a memory block selection address. When the number of times of rewriting in a first memory block which is a rewriting request object exceeds a predetermined value, data in a second memory block is transferred to the first memory block. Data to be written is written to the second memory block. Therefore, it is possible to increase the number of times of rewriting in the flash memory.
摘要:
Disclosed is a power supply circuit that, at a first node, generates a read voltage and a write voltage for a memory cell. According to the present invention, a power supply circuit comprises: a boosting circuit, for boosting to a first voltage the voltage at the first node when a writing operation is initiated; a capacitor, one end of which is connected to the first node and the other end of which is connected to a second node; a driver circuit, for changing from a second to a third voltage the voltage at the first node when a reading operation is initiated; and a connection circuit, for electrically connecting the first node to the second node when the writing operation is initiated.
摘要:
A booster circuit is disclosed, the booster circuit having a plurality of booster cells tandem-connected, each of the boosters having a transfer transistor and a capacitor, an input terminal, a drain, and a gate of the transfer transistor being connected, a source of the transfer transistor being an output terminal, a first terminal of the capacitor being connected to the source of the transfer transistor, a clock signal being supplied to a second terminal of the capacitor, wherein the transfer transistor is composed of a triple-well having a first well and a second well, the first well being formed on a semiconductor substrate, the second well being formed on the first well, and wherein the semiconductor substrate is connected to a reference voltage, a diffusion layer in the first well, a first diffusion layer in the second well, a second diffusion layer in the second well, the first terminal of the capacitor, and the gate of the transfer transistor being connected, the conduction type of the first well being the same as the conduction type of the diffusion layer in the first well, the conduction type of the second well being the same as the conduction type of the first diffusion layer in the second well, the conduction type of the second well being different from the conduction type of the second diffusion layer in the second well.
摘要:
A plurality of memory cells are arranged in lattice arrangement to form a memory cell array. Each of the memory cells is provided with a source. Data in the memory cell can be electrically written and erased. Sources of all the memory cells are connected in common. Also, a source voltage control circuit having two or more kinds of load characteristics is connected to the sources connected in common. According to a load characteristics selected from a plurality of load characteristics, source voltage of the memory cell is controlled.
摘要:
In an input protection circuit, a bipolar protection device is constituted of a semiconductor substrate of a first conductivity type, a first diffused layer of a second conductivity type formed in the substrate and connected to an input signal pad, a second diffused layer of the second conductivity type formed in the substrate to extend in parallel to the first diffused layer but separately from the first diffused layer by a first space, and a third diffused layer of a high impurity concentration and of the first conductivity type formed in the first space in the substrate to extend in parallel to the first and second diffused layers, in junction with the second diffused layer but separately from the first diffused layer. When a backward biasing voltage is applied, the thickness of a depletion layer formed is made large, so that generation of hot carriers is minimized. Thus, increase of a leakage current caused because hot carriers generated by application of an overvoltage were injected into a field oxide film, can be prevented.