SN74LVC2T45DCTR

This dual-bit noninverting bus transceiver uses two
separate configurable power-supply rails. The A port
is designed to track VCCA. VCCA accepts any supply
voltage from 1.65V to 5.5V. The B port is designed
to track VCCB. VCCB accepts any supply voltage from
1.65V to 5.5V. This allows for universal low-voltage
bidirectional translation between any of the 1.8V, 2.5V,
3.3V, and 5V voltage nodes.
The SN74LVC2T45 is designed for asynchronous
communication between two data buses. The logic
levels of the direction-control (DIR) input activate
either the B-port outputs or the A-port outputs. The
device transmits data from the A bus to the B bus
when the B-port outputs are activated, and from the
B bus to the A bus when the A-port outputs are
activated. The input circuitry on both A and B ports
are always active and must have a logic HIGH or
LOW level applied to prevent excess ICC and ICCZ.
The SN74LVC2T45 is designed so that VCCA supplies
the DIR input circuit. 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.
The VCC isolation feature is designed so that if either
VCC input is at GND, both ports are in the highimpedance state.