NON VOLATILE SEMICONDUCTOR MEMORY DEVICE

摘要

PURPOSE:To realize writing with high reliability for a short time by determining an electric potential for a connecting point of the first and second electric current mirror circuits in relation to electric current characteristics of a p,n MIS electric field effect type transistor. CONSTITUTION:At the first electric current mirror circuit 8, an input terminal 11 is connected to a connecting point 15 and an output terminal 12 is connected to a connecting point 16. At the second electric current mirror circuit 9, an input terminal 14 is connected to a dummy electric current source 10 which generates the electric current set beforehand and an output terminal 13 is connected to a connecting point 16. The output terminal 12 of the first electric current mirror circuit 8 and the output terminal 13 of the second electric current mirror circuit 9 are connected with the connecting point 16, and the electric potential of the connecting point 16 becomes an electric potential V16 which is determined in relation to the electric current characteristics with p-MISTQ15 and n-MISTQ17. When the electric curring IM which flows at a memory transistor Q11 is smaller than the electric circuit IO of the dummy electric current source set beforehand, V16 becomes lower and adversely, when IM is larger than IO, V16 becomes higher.