A FIFO memory is a storage device that allows data to be written into and read from its array at independent data rates. The SN74ALVC7804 is an 18-bit FIFO with high speed and fast access times. Data is processed at rates up to 40 MHz with access times of 18 ns in a bit-parallel format. The SN74ALVC7804 is designed for 3-V to 3.6-V V_CC operation.

Data is written into memory on a low-to-high transition of the load clock (LDCK) and is read out on a low-to-high transition of the unload clock (UNCK). The memory is full when the number of words clocked in exceeds the number of words clocked out by 512. When the memory is full, LDCK has no effect on the data residing in memory. When the memory is empty, UNCK has no effect.