摘要:
The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite operation, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
摘要:
The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite operation, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
摘要:
In a nonvolatile semiconductor memory device, a wiring layer is connected between a power source and a memory cell. Resistance of the wiring layer is larger than the on-resistance of a load transistor, so that the load transistor substantially determines the load characteristic. Therefore, the load characteristic curve is more gentle in inclination and more rectilinear in shape. This makes the data writing operation stable against a variance in the channel lengths of manufactured transistors forming the memory cells.
摘要:
A voltage detecting circuit comprising a voltage-input terminal for receiving a first voltage or a second voltage higher than the first voltage, switch means connected between the voltage-input terminal and a first node, and an inverter circuit having an input terminal coupled to the first node and an output terminal coupled to a second node. The switch circuit is turned on when the voltage at the voltage-input terminal is higher than a predetermined value which is between the higher than the first voltage and lower than the second voltage, and is turned off when the voltage at the voltage-input terminal is lower than the predetermined value. The inverter circuit includes a first transistor having a source-drain path coupled between a first power-source potential terminal and the second node, a current control section for maintaining a current flowing through the source-drain path of the first transistor at a predetermined value, and a second transistor having a source-drain path connected between the second node and a second power-source potential terminal and a gate coupled to the first node.
摘要:
An electrostatic discharge protection circuit is provided with a variable threshold for limiting the potential of an input signal having a given high or low voltage, and is adapted to an EPROM containing an input MOS transistor which is responsive to the input signal. The protection circuit is associated with an input terminal for receiving the input signal. The input terminal is coupled to the gate of the input MOS transistor. The protection circuit also includes a circuit element for limiting or suppressing the input signal potential at the variable threshold. The gate of the input MOS transistor receives the potential limited signal from the circuit element. The circuit element is responsive to a given threshold control potential. The variable threshold is enhanced by the given threshold control potential when a high-voltage input signal is applied to the input terminal.
摘要:
A semiconductor device comprises a plurality of data supply circuits, output circuits for producing a plurality of data delivered from the data supply circuit and delay circuit for transferring respective data from each data supply circuit to a different output circuit with a different delay time. Each data supply circuit includes a plurality of row lines, a row decoder for selecting the row line in response to an address signal, a plurality of memory cell arrays including memory cells selectively driven by the row line and storing data, a plurality of column lines to receive data read out from the memory cell array, and a column decoder for selecting said column lines. The delay circuit prevents a plurality of data from being simultaneously outputted.
摘要:
A semiconductor integrated circuit comprises a first MOS transistor connected at the drain to a power source terminal of a high potential power source and supplied at the gate with a predetermined voltage, a logic circuit including MOS transistors provided between the power source terminal and a circuit point at a potential and operating in a potential range between the high potential and the circuit point, and a circuit for making the potential at the circuit point coincide with the potential at the source of the first MOS transistor.
摘要:
A current-controlling MOS transistor is connected between a power source and an MOS circuit. A control voltage which has a level related to temperature is applied to the gate electrode of the control MOS transistor in order to compensate for current reduction at high temperatures due to the lowering of the mobility of minority carriers. The response time of the MOS circuit is made less dependent on temperature as a result of the current compensation.
摘要:
In a nonvolatile semiconductor memory device using as memory cells insulated-gate type field effect transistors each having source and drain regions, a floating gate electrode, and a control gate electrode, the width of the floating and control gate electrodes is narrower at those portions which are located over a channel between the source and drain regions in each memory cell than at those portions which are not located over the channel.
摘要:
A memory device utilizing metal oxide semiconductor field effect transistors (MOS FETs) formed in a semiconductor substrate. The memory device is so improved as to be accessed without a delay and as not to behave erroneously, in spite of a potential variation of data line or the semiconductor substrate. It comprises a plurality of row lines for supplying input signals, a plurality of column lines for supplying output signals, decoders for selecting any one of these lines, a plurality of memory cells connected to the row and column lines in a specific manner, a voltage sensing circuit connected to the column lines, a first potential source connected to the column lines, a second potential source for supplying the memory cells with a source voltage, and means for holding the column lines at a potential substantially equal to the voltage supplied from the second potential source when the potential of the column lines or the substrate varies.