Non-volatile semiconductor memory device having an improved testing mode

Abstract

An EEPROM device comprises a memory cell array having a plurality of non-volatile memory cells respectively disposed at locations defined by word lines and bit lines and memorizing pieces of data information in a rewriteable manner, respectively, a row address decoder circuit responsive to an address signal indicative of a row address for selectively activating one of the word lines, a column address decoder circuit responsive to an address signal indicative of a column address for selecting one of the bit lines, and a data control unit selectively carrying out erasing, write-in and read-out operations on one of the non-volatile memory cells, in which the row address decoder circuit is further operative to concurrently activate every second word line in the presence of the row address signal indicative of a first state and to concurrently activate the other word lines in the presence of the row address signal indicative of a second state in a testing mode of operation, and in which the data control unit carries out the erase and write-in operations on a plurality of the non-volatile memory cells coupled to the word lines to be activated in the testing mode of operation.