The storage device that includes a non-volatile memory with a control circuitry that is communicatively coupled to an array of memory cells that are arranged in a plurality of word lines. The control circuitry is configured to program the memory cells in a plurality of programming loops. The programming loops include applying a programming pulse to a selected word line of the plurality of word lines. The programming loops also include applying a verify pulse V.sub.N to the selected word line to simultaneously verify a lower tail of the memory cells being programmed to a data state N and an upper tail of the memory cells that have been programmed to a data state N−1. The data state N−1 has a lower voltage threshold than the data state N.

Apparatuses and techniques are described for detecting and compensating for a set of memory cells having a slow program speed, based on a comparison between the number of program loops used to complete programming for different data states. A program loop (PL) number is stored when programming is completed for memory cells of each assigned data state. The PL number of an nth state is then compared to the PL number of another state such as the n−1st state. If the difference between the PL numbers exceeds a threshold, the set of memory cells is considered to be slow programming and a compensation is triggered. The compensation can involve increasing the program pulse width in each remaining program pulse of the program operation. In another approach, the compensation can be triggered and subsequently deactivated in the program operation.

Apparatus and methods are described to reduce program disturb for a memory string with a partial select gate drain, which is partially cut by a shallow trench. The memory string with a partial select gate drain is linked with a neighboring full select gate drain that during its programming can casuse a program disturb in the memory string with a partial select gate drain. The bias voltage applied to the selected full select gate drain can be controlled from a high state for low memory program states to a lower state for the high memory program states. The high data states may cause program disturb. The reduction in the bias voltage can match a reduction in the bias voltage applied to the bit lines to reduce the program disturb while providing adequate signal to program the high states on the memory string of the full select gate drain.

To improve programming performance for a non-volatile memory , the verification of multiple programming levels can be performed based on a single discharge of a sensing capacitor through a selected memory cell by using different voltage levels on a second plate of the sensing capacitor: after discharging a first plate of the sensing capacitor through the selected memory cell, a result amount of charge is trapped on the first plate, which is then used to set first and second control gate voltages on a sensing transistor whose control gate is connected to the first place of the sensing capacitor based on respectively setting the second plate of the sensing capacitor to first and second voltage levels. To further improve programming performance, when the non-volatile memory stores in a multistate format, after the next to highest data state finishes programming, the next programming pulse can use a larger step size.

A memory device includes a memory block, a peripheral circuit, and control logic. The memory block includes memory cells. The peripheral circuit performs a program operation including a plurality of program loops. Each of the plurality of program loops includes a program pulse application operation and a verify operation. The control logic controls the peripheral circuit to store cell status information and apply a program limit voltage. The control logic sets a verify pass reference and applies the program limit voltage determined based on the cell status information.

Described are systems and methods for performing memory programming operations in the overwrite mode. An example memory device comprises: a memory array comprising a plurality of memory cells electrically coupled to a plurality of wordlines and a plurality of bitlines; and a controller coupled to the memory array, the controller to perform operations comprising: responsive to identifying a first data item to be stored by a portion of the memory array, causing a first memory programming operation to be performed to program, to a first target threshold voltage, a set of memory cells comprised by the portion of the memory array; and responsive to identifying a second data item to be stored by the portion of the memory array, causing a second memory programming operation to be performed to program the set of memory cells to a second target threshold voltage exceeding the first target threshold voltage.

Numerous embodiments of a precision tuning algorithm and apparatus are disclosed for precisely and quickly depositing the correct amount of charge on the floating gate of a non-volatile memory cell within a vector-by-matrix multiplication (VMM) array in an artificial neural network. Selected cells thereby can be programmed with extreme precision to hold one of N different values.

A semiconductor memory device includes a memory block and a peripheral circuit. The memory block includes normal pages and buffer pages. Each of the normal pages includes memory cells that store the N bits of data. Each of the buffer pages includes memory cells that store one bit of data. The peripheral circuit receives a first page data and performs a single level cell (SLC) program on the first page data in a first buffer page. In addition, the peripheral circuit receives a second page data and performs the SLC program on the second page data in a second buffer page. In addition, the peripheral circuit performs a multiple-level program operation on a normal page based on the first and second page data programmed in the first and second buffer page, respectively.

A method of operating a non-volatile memory device includes performing a first sensing operation on the non-volatile memory device during a first sensing time including a first section, a second section, and a third section. The performing of the first sensing operation includes applying a first voltage level, which is variable according to a first target voltage level, to a selected word line in the first section, applying a second voltage level, which is different from the first voltage level, to the selected word line in the second section, and applying the first target voltage level, which is different from the second voltage level, to the selected word line in the third section. The first voltage level becomes greater as the first target voltage level becomes greater.

There are provided a semiconductor memory device and a method for operating the same. The semiconductor memory device includes: a memory cell array with a plurality of memory cells programmed to a plurality of program states; a peripheral circuit configured for performing a program operation on selected memory cells among the plurality of memory cells through a plurality of program loops; a current sensing circuit for determining a verify result of each of the plurality of program states by performing an individual state current sensing operation on the selected memory cells among the memory cells; and a control logic for controlling the current sensing circuit to perform the individual state current sensing operation, based on a number of program loops, among a plurality of program loops, that are performed.