A memory device including a memory array with a plurality of memory macros, a power supplying circuit, and a controller is provided. The power supplying circuit is coupled to the memory array. The controller is coupled to the memory array. The power supplying circuit is configured to provide power to perform write operations to a number of the memory macros at the same time. The number of the memory macros for the write operations performed at the same time is not higher than a maximum number of the memory macros. The controller obtains the maximum number of the memory macros for the write operations performed at the same time by the power supplying circuit. The controller re-arranges a schedule for a sequence of the write operations of the memory macros to generate a re-arranged schedule. The maximum number is taken as a threshold value. In the re-arranged schedule, a number of part of the memory macros for the write operations performed at the same time is equal to or less then the threshold value.