A memory device is provided. The memory device includes: a memory cell configured to store weight data, a buffer memory configured to read the weight data from the memory cell, an input/output pad configured to receive input data and a multiply-accumulate (MAC) operator configured to receive the weight data from the buffer memory and receive the input data from the input/output pad to perform a convolution operation of the weight data and the input data, wherein the input data is provided to the MAC operator during a first period, and wherein the MAC operator performs the convolution operation of the weight data and the input data during a second period overlapping with the first period.