A memory device having a plurality of voltage regions and a method of operating the same are provided. The memory device includes a memory cell array, a data path region including data processing blocks transmitting read/write data from/to the memory cell array during read/write operations, and a control signal path region including control blocks controlling the data processing blocks during the read/write operations. The data path region selectively receives a first high power voltage or a first low power voltage in accordance with an operating mode of the memory device. The control signal path region receives the first high power voltage regardless of the operating mode.