STRESS VOLTAGE APPLICATION CIRCUIT CAPABLE OF APPLYING STRESS IN UNITS OF BLOCK

摘要

PROBLEM TO BE SOLVED: To obtain a stress voltage applying circuit which can apply sufficient stress voltage to quickly find out cells which are not seriously faulty. SOLUTION: Any one of the row blocks B1 to B10 is selected by a block selection control circuit 20 depending on a block selection signal by means of the address decoding. When the stress voltage application object is a row block B1, a path voltage which is boosted up on the basis of a program voltage is applied to the gates of transistors T1 to T4 by means of a block selection control circuit 20A depending on the block selection signal, and a stress voltage is applied to the gates of selected transistor groups 2A, 2D via the transistors T1, T4. Moreover, the stress voltage offered by a word line selection control circuit 30 is applied to the word line via transistors T2, T3. With application of the stress voltage in unit of block, even if there is a serious defective cell which drops stress voltage in certain block, sufficient stress voltage may be applied to the cells in the other blocks, which are not seriously faulty.