The SN74BCT574DW is an octal edge-triggered D-type Flip-flop feature 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads. They are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers and working registers. On the positive transition of the clock input, the Q outputs are set to the logic levels that were set up at the data (D) inputs. 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. To ensure the high-impedance state during power up or power down, OE\ should be tied to VCC through a pull-up resistor.
