摘要:
In a defect relieving technology which replaces defective memory cells of a semiconductor memory device by spare memory cells, use is made of an associative memory. Address information of a defective memory cell is stored as a reference data of the associative memory, and new address information of a spare memory cell is written down as output data of the associative memory. A variety of improvements are made to the associative memory. For instance, a plurality of coincidence detection signal lines of the associative memory are divided into at least two groups, and one group among them is selected by switching means. Reference data of the associative memory comprises three values consisting of binary information of "0" and "1", and don't care value "X". The associative memory further includes a plurality of electrically programable non-volatile semiconductor memory elements.
摘要:
A semiconductor memory device is proposed wherein at least an array comprising a plurality of memory cells each having at least one capacity, a select mechanism for specifying the position of each memory cell, data lines connected to said memory cells for transmitting the data and a data writing and a data reading mechanisms are provided. The feature of this device lies in that the voltage generator for serially generating three or more values of the voltage which are different from each other and the means for applying said voltage to said memory cells are provided on the same semiconductor board as the same said memory cells, and as the said reading mechanism the column register is provided which, as said reading mechanism, has the mechanism for deciding the data, transfer gate which is provided between said deciding means and said data line, and the bias charge transfer mechanism which is provided between said transfer gate and said deciding mechanism, and having at least two or more memory elements for temporarily storing said decided data.
摘要:
In a semiconductor memory for reading and writing of stored charge in an X-Y address system by arranging a plurality of memory cells each including a capacitance element and one MOS-FET in matrix, this invention discloses a semiconductor memory using multiple level storage structure for read and write of at least more than two multi-level data stored in the capacitance elements, by applying a multi-level step voltage to the plate electrode of the capacitance or to the gate electrode of MOS-FET so as to write and read signal charge.
摘要:
A semiconductor memory having an error correcting function is provided, which has a device by which the user finds no difficulty in making use of the semiconductor memory and can test it with ease. In the semiconductor memory, a signal indicative of the completion of the preparation for reading/writing is outputted from the memory so that the user, after detecting the output of this signal, performs reading/writing data. To facilitate tests, such as a memory cell test for a redundant bit (check bit), an encoding circuit test and a decoding circuit test, the present invention provides that the arranged tests can be made independently of each other.
摘要:
In a semiconductor memory includes a memory array consisting of a plurality of memory cells respectively having at least one storage capacitor, an addressing circuit which designates location of each memory cell, data lines which transmit data connected to said memory cells and data writing and reading circuits connected to said data lines. The semiconductor memory has a multiple level storage structure. In particular, the memory includes an arrangement for sequentially applying, on a time series basis, different voltages of at least 3 levels or more to the gate of a switching MOS transistor of said memory cells, a bias charge supplying means as said data reading circuit and a column register providing at least two or more storage cells which temporarily store said data.
摘要:
A highly integrated memory features increased reading speed and writing speed. A sense circuit for this memory including a memory cell array having a plurality of memory cells each of which including at least one insulated gate field effect transistor, and a plurality of data lines to which the memory cells are connected. The memory also includes an address selection mechanism which is capable of selecting a memory cell out of a plurality of memory cells and connecting it to the data line. A sense amplifier a mechanism which is connected to the data line and amplifies a voltage according to the data of a memory cell. A common line (input/output line) is connected to the data lines, via a column switch, where the selection depends upon a column address. A main amplifier is connected to the common line (input/output line), and has at least a mechanism for stabilizing the voltage of the common line (input/output line) and an amplifying mechanism.
摘要:
A highly reliable and high speed ferroelectric memory having a high degree of integration. In a ferroelectric memory having a multiple of memory cells M1, each constituted by one transistor and one ferroelectric capacitor, in the normal operation, the ferroelectric memory is used as a volatile memory in which a voltage on a storage node ST1 stores information in a DRAM mode. Both the electric potential at the plate PL1 of the ferroelectric capacitor and a precharge electric potential on a data line DL1(j) are Vcc/2. When the a power supply voltage is turned on, a polarization state is detected as a ferroelectric memory of a plate electric potential of Vcc/2 and a precharge electric potential of Vss (or Vcc) and the read operation is performed a FERAM mode. The switching between the DRAM mode and the FERAM mode is executed by generating a signal to designate the FERAM mode in the memory along with the turn-on of the power supply and by generating a signal to designate the DRAM mode after completion of the conversion operation from nonvolatile information to volatile information.
摘要:
In a semiconductor memory, switch circuits are provided so as to inhibit voltage and signal supplies to each of the normal memory blocks when so required. On the other hand, a ROM is provided on the chip so as to store the address of a defective memory block which consumes an excessively large stand-by current when the semiconductor memory is in the stand-by mode. The switch circuits are controlled by the output of the ROM so as to inhibit the voltage and signal supply to the defective memory block. Then, a spare memory block which is substituted for the defective normal memory block receives the voltage and signal supply.
摘要:
In a voltage converter provided in a semiconductor device and supplying an internal supply voltage to a circuit in the semiconductor device, a circuit is provided for generating a first voltage whose dependency on an external supply voltage is regulated to a predetermined small value, while another circuit is provided for generating a second voltage whose dependency on the external supplying voltage is larger than the dependency of the first voltage. Another circuit selects the first voltage when the semiconductor device is in a state of a standard operation and selects the second voltage when the device is in another state of operation, such as testing or aging. The selected voltage may be converted by a differential amplifier which is constituted by a load of P-channel MOS transistors and a source-coupled pair of N-channel MOS transistors. An output of the differential amplifier is fed back through a directly coupled voltage lowering circuit which generates the converted output.
摘要:
In a semiconductor memory, switch circuits are provided so as to inhibit voltage and signal supplies to each of the normal memory blocks when so required. On the other hand, a ROM is provided on the chip so as to store the address of a defective memory block which consumes an excessively large stand-by current when the semiconductor memory is in the stand-by mode. The switch circuits are controlled by the output of the ROM so as to inhibit the voltage and signal supply to the defective memory block. Then, a spare memory block which is substituted for the defective normal memory block receives the voltage and signal supply.