The Texas Instruments SN65HVD77DGKR is a full-duplex RS-422/RS-485 transceiver that pushes the data rate to 50 Mbps, putting it in the high-speed tier of the 65HVD7x family. Full-duplex operation means separate transmit and receive pairs, so the bus never needs direction switching — useful for point-to-point links where throughput matters and the protocol can dedicate two twisted pairs.
Housed in an 8-VSSOP (DGK package code), the footprint matches the standard 8-MSOP / 8-TSSOP land pattern — 3.00 mm body width, 0.65 mm pitch. Surface-mount only; no through-hole variant. The small package suits space-constrained I/O cards and compact sensor modules, but the fine pitch means the reflow profile and solder-paste stencil aperture need attention for reliable assembly.
That means no last-time-buy scramble and normal lead times through distribution. For dual-sourcing or a pin-compatible second source, the SN65HVD78 (same footprint, same supply range) drops the data rate to 20 Mbps but adds a lower-power mode — a trade worth knowing if the bus speed requirement is lower and quiescent current matters more.