Circuits and methods for refreshing memory banks in a DRAM are provided. A refresh circuit is provided in a DRAM having at least one memory bank and a plurality of word lines connected to memory locations in the memory bank. The word lines are subdivided into first and second groups of subword lines. The refresh circuit includes a delay circuit, a first driving circuit, and a second driving circuit. The delay circuit receives a refresh signal and outputs a delayed refresh signal a predetermined time delay later. The first driving circuit responds to the refresh signal by driving word lines in the first group of subword lines and the second driving circuit responds to the delayed refresh signal by driving word lines in the second group of subword lines.