Memory-based device

Abstract

A device includes first and second wires, resistors, and a processor. Input signals are transmitted from the first wires through the resistors to the second wires. The processor receives a sum value of the input signals from one of the second wires, and shifts the sum value by a nonlinear activation function to generate a shifted sum value. The processor calculates a backpropagation value based on the shifted sum value and a target value related to a corresponding input signal of the input signals, and generates a pulse number based on the corresponding input signal of the input signal and the backpropagation value. The processor applies a voltage pulse to one of the resistors related to the corresponding input signal based on the pulse number, in order to modify a value of the corresponding input signal in the input signals to be the same as the target value.

What is claimed is: 
     
         1 . A memory-based device, comprising:
 a plurality of first wires;   a plurality of second wires arranged across the plurality of first wires;   a plurality of resistors, wherein each of the plurality of resistors is coupled to one of the plurality of first wires and one of the plurality of second wires, wherein a plurality of input signals are transmitted from the plurality of first wires through the plurality of resistors to the plurality of second wires; and   a processor configured to receive a sum value of the input signals from one of the plurality of second wires, and shift the sum value by a nonlinear activation function to generate a shifted sum value, wherein the processor is configured to calculate a backpropagation value based on the shifted sum value and a target value related to a corresponding input signal of the plurality of input signals, and generate a pulse number based on the corresponding input signal of the plurality of input signals and the backpropagation value, wherein each of a value of the corresponding input signal and the backpropagation value is higher than or equal to a threshold value, wherein the processor is configured to apply a voltage pulse to one of the plurality of resistors related to the corresponding input signal based on the pulse number, in order to modify the value of the corresponding input signal in the plurality of input signals to be the same as the target value.   
     
     
         2 . The device of  claim 1 , wherein the plurality of first wires and the plurality of second wires are arranged to form an array, wherein each of the plurality of resistors located at the same column of the array has a first terminal and a second terminal, the first terminals of the plurality of resistors are coupled to different wires of the plurality of first wires, and the second terminals of the plurality of resistor are coupled to the same wire of the plurality of second wires. 
     
     
         3 . The device of  claim 2 , wherein the processor is configured to respectively shift sum values from the plurality of second wires located in columns of the array by the nonlinear activation function to generate shifted sum values. 
     
     
         4 . The device of  claim 3 , wherein the processor is configured to calculate backpropagation values based on the shifted sum values and a plurality of target values, wherein each of the plurality of target values corresponds to one of the plurality of input signals. 
     
     
         5 . The device of  claim 4 , wherein the processor is configured to compare each of the values of the plurality of input signals with the threshold value, and compare each of the backpropagation values with the threshold value, wherein the processor is configured to generate pulse numbers based on the plurality of input signals and the backpropagation values if each of the plurality of input signals and the backpropagation values is higher than or equal to the threshold value. 
     
     
         6 . The device of  claim 5 , wherein the processor is configured to correspondingly apply voltage pulses to the plurality of resistors, through one of the plurality of first wires and one of the plurality of second wires, based on the pulse numbers, so as to change resistance of the plurality of resistors. 
     
     
         7 . The device of  claim 1 , wherein the nonlinear activation function comprises at least one of a sigmoid function and a rectified linear unit (ReLU) function. 
     
     
         8 . A device, comprising:
 a first net, comprising:
 a plurality of first wires arranged to form a first array; and 
 a plurality of first resistors, wherein each of the plurality of first resistors is disposed at one of areas formed between the plurality of first wires, and coupled to two of the plurality of first wires being across each other; 
   a second net comprising:
 a plurality of second wires arranged to form a second array; and 
 a plurality of second resistors, wherein each of the plurality of second resistors is disposed at one of areas formed between the second wires, and coupled to two of the plurality of second wires being across each other; and 
   a processor configured to obtain first input signals transmitted through the plurality of first resistors to calculate first sum values, provide second signals related to the first sum values to the second net, and obtain second input signals transmitted through the plurality of second resistors to calculate second sum values;   wherein the processor is configured to shift the first sum values and the second sum values by a nonlinear activation function to generate first shifted sum values and second shifted sum values;   wherein the processor is configured to calculate first feedbacks of the first net and second feedbacks of the second net based on the second shifted sum values and a plurality of target values related to a corresponding input signal of the first input signals;   wherein the processor is configured to generate a plurality of first pulse numbers based on the first input signals and the first feedbacks, and generate a plurality of second pulse numbers based on the second input signals and the second feedbacks;   wherein the processor is configured to apply a first voltage pulse to one of the plurality of first resistors based on the plurality of first pulse numbers, and configured to apply a second voltage pulse to one of the plurality of second resistors based on the plurality of second pulse numbers, in order to modify a value of the corresponding input signal of the first input signals to be the same as a corresponding target value of the plurality of target values.   
     
     
         9 . The device of  claim 8 , wherein the processor is configured to compare each of values of the first input signals with a threshold value, compare each of values of the first feedbacks with the threshold value, and generate the first pulse numbers based on the first input signals and the first feedbacks if each of values of the first input signals and the first feedbacks is higher than or equal to the threshold value. 
     
     
         10 . The device of  claim 9 , wherein the processor is configured to compare each of values of the second input signals with the threshold value, compare each of values of the second feedbacks with the threshold value, and generate the second pulse numbers based on the second input signals and the second feedbacks if each of values of the second input signals and the second feedbacks is higher than or equal to the threshold value. 
     
     
         11 . The device of  claim 10 , wherein the processor is configured to shift the first sum values by the nonlinear activation function to generate the first shifted sum values, wherein the processor is configured to shift the second sum values by the nonlinear activation function to generate the second shifted sum values. 
     
     
         12 . The device of  claim 11 , wherein the first feedbacks comprise first backpropagation values, and the second feedbacks comprise second backpropagation values, wherein the processor is configured to calculate the second backpropagation values based on the second shifted sum values and the target values, and calculate the first backpropagation values based on the first shifted sum values and the second backpropagation values. 
     
     
         13 . The device of  claim 12 , wherein the nonlinear activation function comprises at least one of a sigmoid function and a rectified linear unit (ReLU) function. 
     
     
         14 . A device, comprising:
 a plurality of first wires configured to receive a plurality of input signals;   a plurality of second wires;   a plurality of resistors configured to transmit the plurality of input signals to one of the plurality of second wires to generate a sum value; and   a processor configured to:
 shift the sum value by a nonlinear activation function to generate a shifted sum value, 
 calculate a feedback based on the shifted sum value and a target value related to a corresponding input signal of the plurality of input signals, 
 generate a pulse number based on the corresponding input signal and the feedback, 
 apply a voltage pulse to one of the plurality of resistors related to the corresponding input signal based on the pulse number, and 
 modify a value of the corresponding input signal to be the same as the target value. 
   
     
     
         15 . The device of  claim 14 , wherein the processor is further configured to respectively shift a plurality of sum values from the plurality of second wires located in columns of an array by the nonlinear activation function to generate plurality of shifted sum values. 
     
     
         16 . The device of  claim 15 , wherein the processor is further configured to calculate a plurality of feedbacks based on the shifted sum values and a plurality of target values, wherein each of the target values corresponds to one of the plurality of input signals. 
     
     
         17 . The device of  claim 16 , wherein the processor is further configured to:
 compare each of the plurality of input signals with a threshold value,   compare each of the plurality of feedbacks with the threshold value, and   adopt the plurality of input signals and the plurality of feedbacks when the plurality of input signals and the plurality of feedbacks are higher than the threshold value.   
     
     
         18 . The device of  claim 17 , wherein the plurality of feedbacks comprise backpropagation values. 
     
     
         19 . The device of  claim 18 , wherein the processor is further configured to:
 generate a plurality of pulse numbers based on the plurality of input signals and the plurality of feedbacks, and correspondingly apply voltage pulses to the plurality of resistors, through one of the plurality of first wires and one of the plurality of second wires, based on the plurality of pulse numbers, so as to change resistances of the plurality of resistors.   
     
     
         20 . The device of  claim 14 , wherein the nonlinear activation function comprises at least one of a sigmoid function and a rectified linear unit (ReLU) function.