Apparatus and method with in-memory computing

A method performed by a multiply-accumulator (MAC) circuit, the method comprising:

• applying an intermediate voltage to a node by a field-effect transistor connected to the node;
• determining resistance values of a pair of resistive devices based on the intermediate voltage applied to one ends of the pair of resistive devices connected to the node and weight setting voltages applied to the other ends of the pair of resistive devices;
• charging and discharging an electric charge in a capacitor connected to the node by receiving a voltage generated in the node corresponding to a value calculated by multiplying a weight corresponding to a combined resistance value of the pair of resistive devices by an input value corresponding to input voltages individually applied to the other ends of the pair of resistive devices in response to individual resistance values of the pair of resistive devices being determined;
• and
• outputting a voltage based on the charged and discharged electric charge.

A multiplier included in a multiply-accumulator (MAC) circuit, the multiplier comprising:

• a field-effect transistor configured to apply an intermediate voltage to a node;
• a pair of resistive devices having resistance values determined based on the intermediate voltage applied to one ends connected to the node and weight setting voltages applied to the other ends;
• and
• a capacitor configured to be charged and discharged with an electric charge by receiving a voltage generated in the node corresponding to a value calculated by multiplying a weight corresponding to a combined resistance value of the pair of resistive devices and by input value corresponding to input voltages applied individually to the other ends of the pair of resistive devices in response to individual resistance values of the pair of resistive devices being determined.

A method performed by a multiply-accumulator (MAC) circuit, the method comprising:

• writing a weight for a multiplier by applying an intermediate voltage to a node by a field-effect transistor connected to the node, the node corresponding to an end of each of a first resistive device and a second resistive device of the multiplier, and by applying a first weight setting voltage to another end of the first resistive device and a second weight setting voltage to another end of the second resistive device;
• applying an input value to the multiplier by applying a first input voltage to the other end of the first resistive device and a second input voltage to the other end of the second resistive device;
• and
• generating an output value of a neural network node corresponding to a value calculated by multiplying the input value by the weight by discharging a capacitor connected to the node in response to the applying of the input value.