The SN74AUP1T34-Q1 device is a 1-bit noninverting translator that uses two separate configurable power-supply rails. It is a unidirectional translator from A to B. The A port is designed to track VCCA. VCCA accepts supply voltages from 0.9 V to 3.6 V. The B port is designed to track VCCB. VCCB accepts supply voltages from 0.9 V to 3.6 V. This allows for low-voltage translation between 1-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, and 3.3-V voltage nodes. The SN74AUP1T34-Q1 is also 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.
The VCC isolation feature ensures that if VCCA input is at GND, the B port is in the high-impedance state. If VCCB input is at GND, any input to the A side does not cause the leakage current even floating.