CD74HCT40105MT

The CD74HCT40105MT is a 4-bit by 16-word high speed CMOS FIFO Register compatible with the CD40105B,except for 'shift-out' circuitry. It is a low-power first-in-out (FIFO) 'elastic' storage register that can store 16 four-bit words. The 40105 is capable of handling input and output data at different shifting rates. This feature makes particularly useful as a buffer between asynchronous systems. Each work position in the register is clocked by a control flip-flop, which stores a marker bit. A '1' signifies that the position's data is filled and a '0' denotes a vacancy in that position. The control flip-flop detects the state of the preceding flip-flop and communicates its own status to the succeeding flip-flop. When a control flip-flop is in the '0' state and sees a '1' in the preceeding flip-flop, it generates a clock pulse that transfers data from the preceding four data latches into its own four data latches and resets the preceding flip-flop to '0'.