A memory chip and method for operating the same are provided. The memory chip includes a number of pads. The method includes inputting a number of first test signals to the pads respectively, wherein the first test signals corresponding to two physically-adjacent pads are complementary; inputting a number of second test signals, respectively successive to the first test signals, to the pads, wherein the first test signal and the second test signal corresponding to each of the pads are complementary; and outputting expected data from the memory chip if the first test signals and the second test signals are successfully received by the memory chip.