Synchronous memory unit

Abstract

A synchronous memory unit which includes a plurality of input buffers for receiving address data, a plurality of input latches for holding and outputting address data from in the input buffers according to a clock signal, a plurality of decoders for decoding the address data from the input latches, and a memory cell array having a plurality of memory cells which store and output data signals via bit lines according to the address data decoded by the decoders. Also provided are a sense amplifier for amplifying the output data signals on the bit lines, a selector for selecting one of the amplified output data signals according to the address data decoded by the decoders, and a selector output latch for holding and outputting the amplified output data signal from the selector according to the clock signal. An output latch holds and outputs the amplified output data signal from the selector output latch according to the clock signal. An output buffer receives and outputs the amplified output data signal from the output latch. Each latch includes a first latch for holding and outputting a data signal according to the clock signal, a first switch connected to the first latch for allowing a data signal to pass to the first latch according to the clock signal, and a second latch for holding and outputting a data signal according to the clock signal, and a second switch, connected between the first and second latches, for allowing a data signal to pass from the first latch to the second latch according to the clock signal.