Abstract: In one example, a method comprises programming a plurality of analog neural non-volatile memory cells in an array of analog neural non-volatile memory cells to store one of N different values, where Nis a number of different levels that can be stored in any of the analog neural non-volatile memory cells; measuring a current drawn by the plurality of analog neural non-volatile memory cells; comparing the measured current to a target value; and identifying the plurality of the analog neural non-volatile memory cells as bad if the difference between the measured value and the target value exceeds a threshold.

Abstract: Examples for ultra-precise tuning of a selected memory cell are disclosed. In one example, a method of programming a first memory cell in a neural memory to a target value is disclosed, the method comprising programming a second memory cell by applying programming voltages to terminals of the second memory cell; and determining if an output of the first memory cell has reached the target value.

Abstract: A method of operating memory cells includes programming memory cells at a first temperature to different program states associated with first read current values confirmed by using nominal read conditions. Modified read conditions are determined such that a second read current for the one memory cells at a second temperature is approximately equal to the first read current value for the one memory cell. A read operation is performed on the memory cells at the second temperature using the modified read conditions to determine respective third read current values. Error read current values are determined as respective differences between the first and third read current values. Upper and lower program states are assigned to respective desired program states, with read currents that correspond approximately to respective determined error read current values, and are separated approximately by a respective target read current value associated with the respective desired program state.

Abstract: A method and device for erasing a memory cell with a floating gate, by applying successive first erase pulses to the memory cell to remove electrons from the floating gate until a coarse target read current, and then applying successive second erase pulses to the memory cell to remove electrons from the floating gate until a target read current for the memory cell is achieved. The first erase pulses include a first parameter following a first progression that changes in value after respective ones of the first erase pulses. The first progression begins with a first value and ends with a second value. The second erase pulses include the first parameter following a second progression in which the first parameter changes in value after respective ones of the second erase pulses. The second progression begins with a third value that is between, and unequal to, the first and second values.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region disposed between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell columns, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, and fourth lines each electrically connect the drain regions in one of the memory cell columns. The synapses receive a first plurality of inputs as electrical voltages on the first or fourth lines, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: A memory device, and method of formation, that includes a first insulation material disposed over a semiconductor substrate. A first conductive contact extends through the first insulation material. A second block of conductive material is disposed on the first insulation material and on, and in electrical contact with, the first conductive contact. A block of resistive switching dielectric material is disposed directly on the second block of conductive material. A first block of conductive material is disposed directly on the block of resistive switching dielectric material. The block of resistive switching dielectric material and the first block of conductive material are displaced laterally from the first conductive contact. An insulation layer is disposed over the first block of conductive material, the block of resistive switching dielectric material and the second block of conductive material.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell rows, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, fourth lines each electrically connect the drain regions in one of the memory cell columns, and a plurality of transistors each electrically connected in series with one of the fourth lines. The synapses receive a first plurality of inputs as electrical voltages on gates of the transistors, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: In one example, a method comprises determining a logarithmic slope factor for a selected analog non-volatile memory cell in an array of analog non-volatile memory cells while the selected analog non-volatile memory cell is operating in a sub-threshold region; storing the logarithmic slope factor; determining a linear slope factor for the selected analog non-volatile memory cell while the selected analog non-volatile memory cell is operating in a linear region; storing the linear slope factor; and utilizing one or more of the logarithmic slope factor and the linear slope factor when programming the selected analog non-volatile memory cell to a target current.

Abstract: A method of operating memory cells includes programming memory cells at a first temperature to different program states associated with first read current values confirmed by using nominal read conditions. Modified read conditions are determined such that a second read current for the one memory cells at a second temperature is approximately equal to the first read current value for the one memory cell. A read operation is performed on the memory cells at the second temperature using the modified read conditions to determine respective third read current values. Error read current values are determined as respective differences between the first and third read current values. Upper and lower program states are assigned to respective desired program states, with read currents that correspond approximately to respective determined error read current values, and are separated approximately by a respective target read current value associated with the respective desired program state.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region disposed between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell rows, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, and fourth lines each electrically connect the drain regions in one of the memory cell columns. The synapses receive a first plurality of inputs as electrical voltages on the fourth lines, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: In one example, a method of testing a plurality of non-volatile memory cells in an array of non-volatile memory cells, wherein the array is arranged in rows and columns, wherein each row is coupled to a word line and each column is coupled to a bit line, and wherein each word line is selectively coupled to a row decoder and each bit line is selectively coupled to a column decoder, comprises asserting, by the row decoder, all word lines in the array; asserting, by the column decoder, all bit lines in the array; performing a deep programming operation on the array of non-volatile memory cells; and measuring a total current received from the bit lines.

Abstract: Numerous examples of an input function circuit block and an output neuron circuit block coupled to a vector-by-matrix multiplication (VMM) array in an artificial neural network are disclosed. In one example, an artificial neural network comprises a vector-by-matrix multiplication array comprising a plurality of non-volatile memory cells organized into rows and columns; an input function circuit block to receive digital input signals, convert the digital input signals into analog signals, and apply the analog signals to control gate terminals of non-volatile memory cells in one or more rows of the array during a programming operation; and an output neuron circuit block to receive analog currents from the columns of the array during a read operation and generate an output signal.

Abstract: In one example, a method comprises determining a program resolution current value; and setting levels for a programming operation of a plurality of non-volatile memory cells in a neural network array such that a delta current between levels of each pair of adjacent cells in the plurality is a multiple of the program resolution current value.

Abstract: A memory cell array having rows and columns of memory cells with respective ones of the memory cells including spaced apart source and drain regions formed in a semiconductor substrate with a channel region extending there between, a floating gate over a first portion of the channel region, a select gate over a second portion of the channel region, and an erase gate over the source region. A strap region is disposed between first and second pluralities of the columns. For one memory cell row, a dummy floating gate is disposed in the strap region, an erase gate line electrically connects together the erase gates of the memory cells in the one row and in the first plurality of columns, wherein the erase gate line is aligned with the dummy floating gate with a row direction gap between the erase gate line and the dummy floating gate.

Abstract: Numerous embodiments of a precision programming 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.

Abstract: In one example, a method comprises erasing at the same time a word of non-volatile memory cells in an array of non-volatile memory cells arranged into rows and columns, each non-volatile memory cell comprising a word line terminal, a bit line terminal, and an erase gate terminal, by turning on an erase gate enable transistor coupled to erase gate terminals of the word of non-volatile memory cells.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region disposed between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell rows, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, and fourth lines each electrically connect the drain regions in one of the memory cell columns. The synapses receive a first plurality of inputs as electrical voltages on the fourth lines, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell rows, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, fourth lines each electrically connect the drain regions in one of the memory cell columns, and a plurality of transistors each electrically connected in series with one of the fourth lines. The synapses receive a first plurality of inputs as electrical voltages on gates of the transistors, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: A neural network device with synapses having memory cells each having a floating gate and a first gate over first and second portions of a channel region disposed between source and drain regions, and a second gate over the floating gate or the source region. First lines each electrically connect the first gates in one of the memory cell columns, second lines each electrically connect the second gates in one of the memory cell rows, third lines each electrically connect the source regions in one of the memory cell rows, and fourth lines each electrically connect the drain regions in one of the memory cell columns. The synapses receive a first plurality of inputs as electrical voltages on the first or fourth lines, and provide a first plurality of outputs as electrical currents on the third lines.

Abstract: In one example, a system comprises a neural network array of non-volatile memory cells arranged in rows and columns; and a logical cell comprising a first plurality of non-volatile memory cells in a first row of the array and a second plurality of non-volatile memory cells in a second row adjacent to the first row; wherein the first plurality of non-volatile memory cells and the second plurality of non-volatile memory cells are configured as one or more coarse cells and one or more fine cells.