Semiconductor memory device having a self-refreshing control circuit

摘要

A semiconductor memory device capable of a self-refreshing operation with a refresh-initiation signal generated in the memory device has a self-refreshing control circuit. A self-refreshing operation is automatically effected, without externally supplied clock signals, with a specific refreshing cycle having an internally set mode entry time period, a burst refresh time period and an internally set pause time period. These time periods are detected by a single counter circuit arranged to count pulses produced from a basic clock pulse signal generated by an oscillator. The burst refreshing is effected with the pulses contained in a pulse signal generated in synchronization with the basic clock pulse signal from the oscillator.