Abstract: Numerous embodiments for reading a value stored in a selected memory cell in a vector-by-matrix multiplication (VMM) array in an artificial neural network are disclosed. In one embodiment, an input comprises a set of input bits that result in a series of input pulses applied to a terminal of the selected memory cell, further resulting in a series of output signals that are summed to determine the value stored in the selected memory cell. In another embodiment, an input comprises a set of input bits, where each input bit results in a single pulse or no pulse being applied to a terminal of the selected memory cell, further resulting in a series of output signals which are then weighted according to the binary bit location of the input bit, and where the weighted signals are then summed to determine the value stored in the selected memory cell.

Abstract: Numerous embodiments are disclosed for a high voltage generation algorithm and system for generating high voltages necessary for a particular programming operation in analog neural memory used in a deep learning artificial neural network. In one example, a method for programming a plurality of non-volatile memory cells in an array of non-volatile memory cells, comprises generating a high voltage, and programming a plurality of non-volatile memory cells in an array using the high voltage when a programming enable signal is asserted and providing a feedback loop to maintain the high voltage while programming the plurality of non-volatile memory cells.

Abstract: Numerous examples are disclosed for performing calibration of various electrical parameters in a deep learning artificial neural network. In one example, a system comprises a digital-to-analog converter for receiving an input of k bits and generating a first analog output, a mapping scalar for converting the first analog output into a second analog output, and an analog-to-digital converter for generating an output of n bits from the second analog output, where n is a different value than k.

Abstract: A method of scanning N×N pixels using a vector-by-matrix multiplication array by (a) associating a filter of M×M pixels adjacent first vertical and horizontal edges, (b) providing values for the pixels associated with different respective rows of the filter to input lines of different respective N input line groups, (c) shifting the filter horizontally by X pixels, (d) providing values for the pixels associated with different respective rows of the horizontally shifted filter to input lines, of different respective N input line groups, which are shifted by X input lines, (e) repeating steps (c) and (d) until a second vertical edge is reached, (f) shifting the filter horizontally to be adjacent the first vertical edge, and shifting the filter vertically by X pixels, (g) repeating steps (b) through (e) for the vertically shifted filter, and (h) repeating steps (f) and (g) until a second horizontal edge is reached.

Abstract: Numerous examples are described for providing an artificial neural network system comprising an analog array and a digital array. In certain examples, an analog array and a digital array are coupled to shared bit lines. In other examples, an analog array and a digital array are coupled to separate bit lines.

Abstract: Numerous embodiments are disclosed for splitting a physical array into multiple arrays for separate vector-by-matrix multiplication (VMM) operations. In one example, a system comprises an array of non-volatile memory cells arranged into rows and columns; and a plurality of sets of output lines, where each column contains a set of output lines; wherein each row is coupled to only one output line in the set of output lines for each column.

Abstract: Numerous examples are disclosed for an output block coupled to a non-volatile memory array in a neural network and associated methods. In one example, a circuit for converting a current in a neural network into an output voltage comprises a non-volatile memory cell comprises a word line terminal, a bit line terminal, and a source line terminal, wherein the bit line terminal receives the current; and a switch for selectively coupling the word line terminal to the bit line terminal; wherein when the switch is closed, the current flows into the non-volatile memory cell and the output voltage is provided on the bit line terminal.

Abstract: Numerous examples of summing circuits for a neural network are disclosed. In one example, a circuit for summing current received from a plurality of synapses in a neural network comprises a voltage source; a load coupled between the voltage source and an output node; a voltage clamp coupled to the output node for maintaining a voltage at the output node; and a plurality of synapses coupled between the output node and ground; wherein an output current flows through the output node, the output current equal to a sum of currents drawn by the plurality of synapses.

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 columns, 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 second lines, and provide a first plurality of outputs as electrical currents on the third or fourth lines.

Abstract: Numerous examples are disclosed for verifying a weight programmed into a selected non-volatile memory cell in a neural memory. In one example, a circuit comprises a digital-to-analog converter to convert a target weight comprising digital bits into a target voltage, a current-to-voltage converter to convert an output current from the selected non-volatile memory cell during a verify operation into an output voltage, and a comparator to compare the output voltage to the target voltage during a verify operation.

Abstract: Two or more physical memory cells are grouped together to form a logical cell that stores one of N possible levels. Within each logical cell, the memory cells can be programmed using different mechanisms. For example, one or more of the memory cells in a logical cell can be programmed using a coarse programming mechanism, one or more of the memory cells can be programmed using a fine mechanism, and one or more of the memory cells can be programmed using a tuning mechanism. This achieves extreme programming accuracy and programming speed.

Abstract: Numerous embodiments for reading a value stored in a selected memory cell in a vector-by-matrix multiplication (VMM) array in an artificial neural network are disclosed. In one embodiment, an input comprises a set of input bits that result in a series of input pulses applied to a terminal of the selected memory cell, further resulting in a series of output signals that are summed to determine the value stored in the selected memory cell. In another embodiment, an input comprises a set of input bits, where each input bit results in a single pulse or no pulse being applied to a terminal of the selected memory cell, further resulting in a series of output signals which are then weighted according to the binary bit location of the input bit, and where the weighted signals are then summed to determine the value stored in the selected memory cell.

Abstract: Numerous embodiments of analog neural memory arrays are disclosed. In one embodiment, a system comprises a first array of non-volatile memory cells, wherein the cells are arranged in rows and columns and the non-volatile memory cells in one or more of the columns stores W+ values, and wherein one of the columns in the first array is a dummy column; and a second array of non-volatile memory cells, wherein the cells are arranged in rows and columns and the non-volatile memory cells in one or more of the columns stores W? values, and wherein one of the columns in the second array is a dummy column; wherein pairs of cells from the first array and the second array store a differential weight, W, according to the formula W=(W+)?(W?).

Abstract: Numerous embodiments for improving an analog neural memory in a deep learning artificial neural network as to accuracy or power consumption as temperature changes are disclosed. In some embodiments, a method is performed to determine in real-time a bias value to apply to one or more memory cells in a neural network. In other embodiments, a bias voltage is determined from a lookup table and is applied to a terminal of a memory cell during a read operation.

Abstract: Numerous embodiments of a transceiver for providing high voltages for use during erase or program operations in a non-volatile memory system are disclosed. In one embodiment, a transceiver comprises a PMOS transistor and a native NMOS transistor. In another embodiment, a transceiver comprises a PMOS transistor, an NMOS transistor, and a native NMOS transistor.

Abstract: Numerous embodiments of circuitry for a set-while-verify operation and a reset-while verify operation for resistive random access memory cells are disclosed. In one embodiment, a set-while-verify circuit for performing a set operation on a selected RRAM cell in the array applies a combination of voltages or current to a bit line, word line, and source line associated with the selected RRAM cell and stops said applying when the set operation is complete. In another embodiment, a reset-while-verify circuit for performing a reset operation on a selected RRAM cell in the array applies a combination of voltages or current to a bit line, word line, and source line associated with the selected RRAM cell and stops said applying when the reset operation is complete.

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 columns, 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 second lines, and provide a first plurality of outputs as electrical currents on the third or fourth lines.

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: Examples of programming circuits and methods are provided. In one example, an adjustable programming circuit comprises a first adjustable voltage divider; a second adjustable voltage divider; a first operational amplifier, wherein an output terminal of the first operational amplifier provides a first programming voltage; and a second operational amplifier, wherein the first input terminal of the second operational amplifier is coupled to the output terminal of the second operational amplifier and the first input terminal of the second operational amplifier is coupled to the second output terminal of the first adjustable voltage divider.

Abstract: Examples of programming circuits and methods are disclosed. In one example, an adjustable programming circuit for generating a programming voltage is disclosed, the circuit comprising an operational amplifier comprising a first input terminal, a second input terminal, and an output terminal, the first input terminal receiving a reference voltage; a first switched capacitor network coupled between the second input terminal of the operational amplifier and the output terminal of the operational amplifier; and a second switched capacitor network coupled between an input voltage and the second input terminal of the operational amplifier; wherein the output terminal of the operational amplifier outputs a programming voltage that varies in response to a capacitance of the first switched capacitor network and a capacitance of the second switched capacitor network.