描述 Description

This dual-bit noninverting bus transceiver uses two separateconfigurable power-supply rails. The A port is designed to trackVCCA. VCCA accepts any supply voltage from 1.65V to 5.5V. The Bport is designed to track VCCB. VCCB accepts any supply voltagefrom 1.65V to 5.5V. This allows for universal low Voltagebidirectional translation between any of the 1.8V, 2.5V, 3.3V, and5V voltage nodes.The U74LVC2T45 is designed for asynchronouscommunication between two data buses. The logic levels of thedirection-control (DIR) input activate either the B-port outputs or theA-port outputs. The device transmits data from the A bus to the Bbus when the B-port outputs are activated, and from the B bus tothe A bus when the A-port outputs are activated. The input circuitryon both A and B ports always is active and must have a logic HIGHor LOW level applied to prevent excess ICC and ICCZ.The U74LVC2T45 is designed so that the DIR input circuit issupplied by VCCA. This device is fully specified forpartial-power-down applications using IOFF. The IOFF circuitrydisables the outputs, preventing damaging current backflowthrough the device when it is powered down.The VCC isolation feature ensures that if either VCC input is atGND, both ports are in the high-impedance state.

特性 Features

Fully Configurable Dual-Rail Design Allows Each Port to OperateOver the Full 1.65-V to 5.5-V Power-Supply Range VCC Isolation Feature: If Either VCC Input Is at GND, Both PortsAre in the High-Impedance State ±24mA Output Drive at 3.3V IOFF Supports Partial-Power-Down Mode Operation