The 74ALVT16501 is a high-performance Bipolar Complementary Metal Oxide Semiconductor (BiCMOS) product designed for V_CC operation at 2.5 V and 3.3 V with I/O compatibility up to 5 V. This device is an 18-bit universal transceiver featuring non-inverting 3-state bus compatible outputs in both send and receive directions.

Data flow in each direction is controlled by output enable (OEAB and OEBA), latch enable (LEAB and LEBA), and clock (CPAB and CPBA) inputs.

For A-to-B data flow, the device operates in the transparent mode when LEAB is HIGH. When LEAB is LOW, the A-bus data is latched if CPAB is held at a HIGH or LOW level. If LEAB is LOW, the A-bus data is stored in the latch/flip-flop on the LOW-to-HIGH transition of CPAB. When OEAB is HIGH, the outputs are active. When OEAB is LOW, the outputs are in the high-impedance state.

Active bus hold circuitry is provided to hold unused or floating data inputs at a valid logic level.

Data flow for B-to-A is similar to that of A-to-B but uses OEBA, LEBA and CPBA. The output enables are complimentary (OEAB is active HIGH and OEBA is active LOW).