The SN74AHCT125D is a quadruple Bus Buffer Gate featuring independent line drivers with 3-state outputs. Each output is disabled when the associated output-enable (OE)\ input is high. When OE\ is low, the respective gate passes the data from the A input to its Y output. To ensure the high-impedance state during power up or power down, OE\ should be tied to VCC through a pull-up resistor and the minimum value of the resistor is determined by the current-sinking capability of the driver.
The SN74AHC1G125DCKR is a single Bus Buffer Gate/Line Driver with 3-state output. The output is disabled when the output-enable (OE) input is high. When output-enable is low, true data is passed from the A input to the Y output. To ensure the high-impedance state during power up or power down, output-enable should be tied to VCC through a pull-up resistor and the minimum value of the resistor is determined by the current-sinking capability of the driver.