SEMICONDUCTOR MEMORY DEVICE WITH READ PROTECTION FUNCTION HAVING READ PROTECTION UNITS INCLUDING REGISTER AND POWER ON DETECTION CIRCUIT

摘要

PURPOSE: A semiconductor memory device with read protection function is provided to prevent data stored in memory cells by having a read protection units. CONSTITUTION: A dynamic random access memory device(100) with read protection function comprises a DRAM core(300) having a well area for plural memory cells storing data, a back-bias voltage generator circuit for generating a back-bias voltage supplied to the well area; a read protection unit(200) for preventing data stored before power-off in the memory cells from being read during power-on. Wherein, the read protection unit supplies either power supply voltage or external power supply voltage in response to the reset command from the outside in order to have equal data value in each memory cell, and dis-activates the back-bias voltage generator circuit.