SN74HCT574PW .

The SN74HCT574PW is an octal edge-triggered D-type Flip-flop with 3-state outputs. It is designed specifically for bus driving. It is particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers and working registers. The eight flip-flops enter data on the low-to-high transition of the clock input. A buffered OE\ input can be used to place the eight outputs in either a normal logic state (high or low logic levels) or the high-impedance state. In the high-impedance state, the outputs neither load nor drive the bus lines significantly. The high-impedance state and increased drive provide the capability to drive bus lines without interface or pull-up components. OE\ does not affect the internal operations of the flip-flops. Old data can be retained or new data can be entered while the outputs are in the high-impedance state.