Apparatus and method for preventing accidental writes from occurring due to simultaneous address and write enable transitions

摘要

A Random Access Memory (RAM) with improved memory access time supporting simultaneous transitions of an address signal and a write enable signal while preventing accidental writes. The RAM includes a memory array, an address transition detector and a race detector. Operation of the memory array is controlled by the address signal and a write clock signal. In response to the write clock's read state the memory array reads data from an address represented by the address signal, while the write clock's write state causes the memory array to write data at the address represented by the address signal. The address transition detector and race detector work together to generate the write clock signal. The address transition detector generates an address transition signal when it detects a transition of the address signal from a representation of a first address of the memory array to a representation of a second address of the memory array. The address transition signal is coupled to the race detector, which, if the write clock is currently in its write state, forces the write clock to its read state before the address signal propagates to the memory array.