1 Features

1• Fully configurable dual-rail design allows each

port to operate with a power supply range from

0.65 V to 3.6 V

• Operating temperature from –40°C to +125°C

• Glitch-free power supply sequencing

• Up to 380 Mbps support when translating from 1.8

V to 3.3 V

• VCC isolation feature

– If either VCC input is below 100 mV, all I/O

outputs are disabled and become high

impedance

• Ioff supports partial-power-down mode operation

• Compatible with AVC family level shifters

• Latch-up performance exceeds 100 mA per JESD

78, Class II

• ESD protection exceeds JESD 22

– 8000-V human-body model (HBM)

– 1000-V charged-device model (CDM)

2 Applications

• Enterprise and communications

• Industrial

• Personal electronics

• Wireless infrastructure

• Building automation

• Point of sale

3 Description

The SN74AXCH2T45 is a two-bit non-inverting bus

transceiver that uses two individually configurable

power-supply rails. The device is operational with

both VCCA and VCCB supplies as low as 0.65 V. The A

port is designed to track VCCA, which accepts any

supply voltage from 0.65 V to 3.6 V. The B port is

designed to track VCCB, which also accepts any

supply voltage from 0.65 V to 3.6 V. Additionally the

SN74AXCH2T45 is compatible with a single-supply

system.

The SN74AXCH2T45 device is designed for

asynchronous communication between data buses.

The device transmits data from the A bus to the B

bus or from the B bus to the A bus, depending on the

logic level of the direction-control input (DIR). The

SN74AXCH2T45 device is designed so the control

pin (DIR) is referenced to VCCA.

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. If a supply is present for VCCA or

VCCB, the bus-hold circuitry always remains active

on the A or B inputs respectively, independent of the

state of the direction control pin.

This device is fully specified for partial-power-down

applications using the Ioff current. The Ioff protection

circuitry ensures that no excessive current is drawn

from or to an input, output, or combined I/O that is

biased to a specific voltage while the device is

powered down.

The VCC isolation feature ensures that if either VCCA

or VCCB is less than 100 mV, both I/O ports enter a

high-impedance state by disabling their outputs.

Glitch-free power supply sequencing allows either

supply rail to be powered on or off in any order while

providing robust power sequencing performance.