The present technology relates to an electronic device. According to the present technology, a memory device having improved verify accuracy may include a memory block including memory cells, a read and write circuit including a plurality of page buffers, a current sensing circuit configured to perform a verify operation of comparing sensing voltages with a reference voltage, and a control logic configured to control the current sensing circuit to perform the verify operation. The control logic controls performing a first verify operation on each of page buffer groups having a same logical group number, and performing a second verify operation on each of page buffer groups having a same physical group number, and the current sensing circuit outputs a verify pass signal in response to both results of the first verify operation and the second verify operation satisfying a pass criterion.

Discussed herein are systems and methods for charging an access line to a non-volatile memory cell during a standby state, such as to prevent or mitigate standby-state charge loss. An embodiment of a memory device comprises a memory cell, a string driver circuit, and a charging circuit. The string driver circuit is coupled to the memory cell via a local word line, and has a common p-well. The charging circuit, in response to a voltage of a global word line of the memory device falling below a reference voltage during a standby state, couple a supply voltage to the common p-well of the string driver circuit to charge the global word line to a positive bias potential. The memory device includes a leakage compensation circuit to compensate for the junction leakage.

Memory devices might include a first latch to store a first data bit; a second latch to store a second data bit; a data line selectively connected to the first latch, the second latch, and a string of series-connected memory cells; and a controller configured to bias the data line during a programing operation of a selected memory cell. The controller may with the first data bit equal to 0 and the second data bit equal to 0, bias the data line to a first voltage level; with the first data bit equal to 1 and the second data bit equal to 0, bias the data line to a second voltage level; with the first data bit equal to 0 and the second data bit equal to 1, bias the data line to a third voltage level; and with the first data bit equal to 1 and the second data bit equal to 1, bias the data line to a fourth voltage level.

According to the one embodiment, a memory system includes a semiconductor memory device and a memory controller. The semiconductor memory device includes: first and second memory cells stacked above a substrate; a first word line coupled to the first and second memory cells; a first bit line coupled to the first memory cell; and a second bit line coupled to the second memory cell. A first state read operation includes a first read operation for reading data from the first memory cell and a second read operation for reading data from the second memory cell. A first read voltage is applied to the first word line during a first period for executing the first read operation, and a second read voltage is applied to the first word line during a second period for executing the second read operation.

A memory system includes a memory array having a plurality of memory cells; and a controller coupled to the memory array, the controller configured to: designate a storage mode for a target set of memory cells based on valid data in a source block, wherein the target set of memory cells are configured with a capacity to store up to a maximum number of bits per cell, and the storage mode is for dynamically configuring the target set of memory cells in as cache memory that stores a number of bits less per cell than the corresponding maximum capacity.

According to the embodiments, an external storage device switches to an interface controller for supporting only a read operation of nonvolatile memory when a shift condition for shifting to a read only mode is met. A host device switches to an interface driver for supporting only the read operation of the nonvolatile memory when determining to recognize as read only memory based on information acquired from the external storage device.

According to one embodiment, a memory system includes a semiconductor memory and a controller. The memory system is capable of executing a first operation and a second operation. In the first operation, the controller issues a first command sequence, the semiconductor memory applies a first voltage to a first word line and applies a second voltage to a second word line to read data from the first memory, and the read data is transmitted to the controller from the semiconductor memory. In the second operation, the controller issues a second command sequence, the semiconductor memory applies a third voltage to the first word line and applies a fourth voltage to the second word line, and data held in the memory cell array is left untransmitted to the controller.

Memory devices might include a first latch to store a first data bit; a second latch to store a second data bit; a data line selectively connected to the first latch, the second latch, and a string of series-connected memory cells; and a controller configured to bias the data line during a programing operation of a selected memory cell. The controller may with the first data bit equal to 0 and the second data bit equal to 0, bias the data line to a first voltage level; with the first data bit equal to 1 and the second data bit equal to 0, bias the data line to a second voltage level; with the first data bit equal to 0 and the second data bit equal to 1, bias the data line to a third voltage level; and with the first data bit equal to 1 and the second data bit equal to 1, bias the data line to a fourth voltage level.

Embodiments of three-dimensional (3D) memory devices with embedded dynamic random-access memory (DRAM) and methods for forming the 3D memory devices are disclosed. In an example, a method for operating a 3D memory device is disclosed. The 3D memory device includes an input/output circuit, an array of embedded DRAM cells, and an array of 3D NAND memory strings in a same chip. Data is transferred through the input/output circuit to the array of embedded DRAM cells. The data is buffered in the array of embedded DRAM cells. The data is stored in the array of 3D NAND memory strings from the array of embedded DRAM cells.

Three-dimensional (3D) memory devices with 3D phase-change memory (PCM) and methods for forming and operating the 3D memory devices are disclosed. In an example, a 3D memory device includes a first semiconductor structure including an array of NAND memory cells, and a first bonding layer including first bonding contacts. The 3D memory device also further includes a second semiconductor structure including a second bonding layer including second bonding contacts, a semiconductor layer and a peripheral circuit and an array of PCM cells between the second bonding layer and the semiconductor layer. The 3D memory device further includes a bonding interface between the first and second bonding layers. The first bonding contacts are in contact with the second bonding contacts at the bonding interface.