A memory macro includes: word lines; memory cells arranged in an array of columns and rows, the rows corresponding to the word lines; and switching circuits corresponding to the columns, each switching circuit being configured to selectively provide a first voltage value of a first voltage source or a different second voltage value of a second voltage source to corresponding voltage supply nodes of the columns; and wherein the word lines are configured to receive the second voltage value as a high logical value of the word lines; a selected one or more of the word lines is activated during a write operation, thereby defining an elapse of the write operation; and each switching circuit is further configured to selectively provide the corresponding first voltage value or the second voltage value substantially for an entirety of the write operation.