The SN74AXC1T45 is a single-bit noninverting bus
transceiver that uses two separate 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.
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.
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.
The glitch suppression circuitry enables either supply rail to be powered on or off in
any order, providing robust power sequencing performance.