A novel memory device is provided. The memory device including a plurality of memory cells arranged in a matrix, and each of the memory cells includes a transistor and a capacitor. The transistor includes a first gate and a second gate, which include a region where they overlap with each other with a semiconductor layer therebetween. The memory device has a function of operating in a “writing mode”, a “reading mode”, a “refresh mode”, and an “NV mode”. In the “refresh mode”, data retained in the memory cell is read, and then the read data is written to the memory cell again for first time. In the “NV mode”, data retained in the memory cell is read, the read data is written to the memory cell again for second time, and then a potential at which the transistor is turned off is supplied to the second gate. The “NV mode” operation enables data to be stored for a long time even when power supply to the memory cell is stopped. The memory cell can store multilevel data.

Methods, systems, and devices for drive strength calibration for multi-level signaling are described. A driver may be configured to have an initial drive strength and to drive an output pin of a transmitting device toward an intermediate voltage level of a multi-level modulation scheme, where the output pin is coupled with a receiving device via a channel. The receiving device may generate, and the transmitting device may receive, a feedback signal indicating a relationship between the resulting voltage of the channel and an value for the intermediate voltage level. The transmitting device may determine and configure the driver to use an adjusted drive strength for the intermediate voltage level based on the feedback signal. The driver may be calibrated (e.g., independently) for each intermediate voltage level of the multi-level modulation scheme. Further, the driver may be calibrated for the associated channel.

The present disclosure relates to circuits, systems, and methods of operation for a memory device. In an example, a memory device includes a plurality of memory cells, each memory cell having a variable impedance that varies in accordance with a respective data value stored therein; and a read circuit configured to read the data value stored within a selected memory cell based upon a variable time delay determination of a signal node voltage change corresponding to the variable impedance of the selected memory cell.

A semiconductor memory cell includes a floating body region configured to be charged to a level indicative of a state of the memory cell; a first region in electrical contact with said floating body region; a second region in electrical contact with said floating body region and spaced apart from said first region; and a gate positioned between said first and second regions. The cell may be a multi-level cell. Arrays of memory cells are disclosed for making a memory device. Methods of operating memory cells are also provided.

A dynamic gain cell memory cell capable of storing multiple values is described herein. In one example, a memory cell may include an input, such as a first transistor. The memory cell may further include a capacitive element coupled to the input, where the capacitive element stores one or more values corresponding to one of multiple voltage levels. A sense transistor configured to operate in source-follower mode may be coupled to the capacitive element, where the charge on the capacitive element controls operation of the sense transistor, such as through a gate of the sense transistor. The memory cell may further include an output connected to the drain of the sense transistor, where current flows through the transistor when the output is activated to access the one or more values stored in capacitive element.

A volatile memory device includes: a first sense amplifier connected to a first memory cell through a first bit line, and configured to sense 2-bit data stored in the first memory cell; a second sense amplifier connected to a second memory cell through a second bit line, and configured to sense 2-bit data stored in the second memory cell, the second bit line having a length greater than a length of the first bit line; and a driving voltage supply circuit configured to supply a first driving voltage to the first sense amplifier, and supply a second driving voltage to the second sense amplifier, the second driving voltage having a voltage level different from a voltage level of the first driving voltage.

The present disclosure relates to circuits, systems, and methods of operation for a memory device. In an example, a memory device includes a plurality of memory cells, each memory cell having a variable impedance that varies in accordance with a respective data value stored therein; and a read circuit configured to read the data value stored within a selected memory cell based upon a variable time delay determination of a signal node voltage change corresponding to the variable impedance of the selected memory cell.

The memory device includes a memory cell array including a plurality of memory cells connected to a plurality of word lines and a plurality of bit lines, a row control circuit including a plurality of row switches corresponding to the word lines, a column control circuit including a plurality of column switches corresponding to the bit lines, and a control logic circuit configured to control pre-charge operations on a word line and a bit line of a selected memory cell and perform a control operation to float the word line and the bit line together after a pre-charge period during a data reading operation. One of the word line and the bit line is floated after the pre-charge period and the other one is pseudo-floated after the pre-charge period.

A semiconductor memory device includes a memory cell array, an error correction circuit and a control logic circuit. The error correction circuit includes an error correction code (ECC) decoder to perform an ECC decoding on a codeword including a main data and a parity data, read from a target page of the memory cell array to correct errors in the read codeword. The control logic circuit controls the error correction circuit based on a command and address from an external memory controller. The ECC decoder has t-bit error correction capability, generates a syndrome based on the codeword using a parity check matrix, performs t iterations during (t−2) cycles to generate an error locator polynomial based on the syndrome, searches error positions in the codeword based on the error locator polynomial and corrects the errors in the codeword based on the searched error positions.

A semiconductor memory cell includes a floating body region configured to be charged to a level indicative of a state of the memory cell; a first region in electrical contact with said floating body region; a second region in electrical contact with said floating body region and spaced apart from said first region; and a gate positioned between said first and second regions. The cell may be a multi-level cell. Arrays of memory cells are disclosed for making a memory device. Methods of operating memory cells are also provided.