The 54AC164245 is a rad-hard advanced high-speed CMOS, Schmitt trigger, 16-bit, bidirectional, multi-purpose transceiver with 3-state outputs and cold sparing. Designed to be used as an interface between a 5 V bus and a 3.3 V bus in mixed 5 V/3.3 V supply systems, it achieves high-speed operations while the CMOS low-power dissipation is kept. All pins have cold spare buffers to change them to high impedance when VDDis tied to ground. This IC is intended for a two-way asynchronous communication between data buses. The direction of the data transmission is determined by the nDIR inputs. The A port interfaces with the 3.3 V bus can also operate at 2.3 V. The B port operates with the 5 V bus. The 54AC164245 is packaged in hermetic ceramic Flat 48-lead screened as per MIL-PRF-38535 to comply with the needs of space applications. It is available with the upper metallic lid either floating or internally connected to ground.