Product-sum calculation unit, neuromorphic device, and product-sum calculation method

A multiply-accumulate calculation device comprising:

• a plurality of first multiple calculation elements, each of the plurality of first multiple calculation elements being a variable resistance element having a write terminal, a common terminal, a read terminal, a variable resistor and a parasitic capacitor, the parasitic capacitors of the plurality of first multiple calculation elements causing transient responses when being charged and transient responses when discharging, the plurality of first multiple calculation elements being configured to generate a weight according to a resistance value of each variable resistor and to generate first output signals by multiplying a first input signal corresponding to an input value by the weight and output the first output signals through the common terminals, the first input signal being input to the read terminal of at least one of the plurality first multiple calculation elements;
• and
• an accumulate calculation unit connected to and receiving the first output signals generated by the plurality of first multiple calculation elements, the accumulate calculation unit being configured to calculate a sum of the first output signals output from the plurality of first multiple calculation elements in a calculation period from a point in time at which transition to a steady state has occurred after transient responses caused by charging to parasitic capacitors of the plurality of first multiple calculation elements according to input of the first input signal to a point in time after transient responses caused by discharging from the parasitic capacitors of the plurality of first multiple calculation elements according to input of the first input signal have started to be generated.

A multiply-accumulate calculation device comprising:

• a plurality of first multiple calculation elements, each of the plurality of first multiple calculation elements being a tunnel magnetoresistance effect element having a variable resistor and a parasitic capacitor, the parasitic capacitors of the plurality of first multiple calculation elements causing transient responses when being charged and transient responses when discharging, the plurality of first multiple calculation elements being configured to generate a weight according to a resistance value of each variable resistor and to generate first output signals by multiplying a first input signal corresponding to an input value by the weight and output the first output signals;
• and
• an accumulate calculation unit connected to and receiving the first output signals generated by the plurality of first multiple calculation elements, the accumulate calculation unit being configured to calculate a sum of the first output signals output from the plurality of first multiple calculation elements in a calculation period from a point in time at which transition to a steady state has occurred after transient responses caused by charging to parasitic capacitors of the plurality of first multiple calculation elements according to input of the first input signal to a point in time after transient responses caused by discharging from the parasitic capacitors of the plurality of first multiple calculation elements according to input of the first input signal have started to be generated.