the aip74lvc1t45; aip74lvch1t45 are single bit, dual supply transceivers with 3-state outputs that enable bidirectional level translation. they feature two 1-bit input-output ports (a and b), a direction control input (dir) and dual supply pins (vcc(a) and vcc(b)). both vcc(a) and vcc(b) can be supplied at any voltage between 1.2 v and 5.5 v making the device suitable for translating between any of the low voltage nodes (1.2v, 1.5v, 1.8v, 2.5v, 3.3v and 5.0v). pins a and dir are referenced to vcc(a) and pin b is referenced to vcc(b). a high on dir allows transmission from a to b and a low on dir allows transmission from b to a.
the devices are fully specified for partial power-down applications using ioff. the ioff circuitry disables the output, preventing any damaging backflow current through the device when it is powered down. in suspend mode when either vcc(a) or vcc(b) are at gnd level, both a port and b port are in the high-impedance off-state.
active bus hold circuitry in the aip74lvch1t45 holds unused or floating data inputs at a valid logic level.