The SN74AXCH1T45 is a single-bit noninverting bus transceiver that uses two individually configurable power-supply rails. The device is operational with both VCCAand VCCBsupplies 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 SN74AXCH1T45 is compatible with a single-supply system.

The DIR pin determines the direction of signal propagation. With the DIR pin configured HIGH, translation is from Port A to Port B. With DIR configured LOW, translation is from Port B to Port A. The DIR pin is referenced to VCCA, meaning that its logic-high and logic-low thresholds track with 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 VCCAor VCCB, the bus-hold circuitry always remains active on the A or B inputs respectively, independent of the state of the direction control pin.Read more