Texas Instruments SN74LVT125

this bus buffer is designed specifically for low-voltage (3.3-v) vcc operation but with the capability to provide a ttl interface to a 5-v system environment. the sn74lvt125 features independent line drivers with 3-state outputs. each output is in the high-impedance state when the associated output-enable (oe)\ input is high. active bus-hold circuitry holds unused or undriven inputs at a valid logic state. use of pullup or pulldown resistors with the bus-hold circuitry is not recommended. this device is fully specified for partial-power-down applications using ioff. the ioff circuitry disables the outputs preventing damaging current backflow through the device when it is powered down. to ensure the high-impedance state during power up or power down oe\ should be tied to vcc through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.