Bus transceiver for 3.3V backplanes
The SN74LVTH16543DL is a 16-bit non-inverting transceiver from the 74LVTH family, organized as two 8-bit elements with independent direction and output-enable controls per byte. This lets a single package handle bidirectional data flow on a 16-bit bus without external muxing. It is not 5 V tolerant on the I/O — feeding 5 V into the bus pins will exceed the recommended operating conditions and may damage the input structures. Level translation from 5 V logic requires an external translator or a 5 V-tolerant family like 74LVTH162245. Output drive is rated 32 mA source / 64 mA sink per channel. The asymmetric sink strength is typical for 3.3 V bus interfaces — it drives the capacitive load of a heavily loaded backplane trace faster on the falling edge, where the noise margin is tighter. For a 50 pF load at 50 MHz, the 64 mA sink current yields a fall time around 2 ns.
56-SSOP footprint and board integration
Housed in a 56-lead SSOP (JEDEC MO-118 variant), 7.50 mm body width, 0.635 mm pitch. The 0.295-inch (7.50 mm) width is wider than the more common 0.300-inch SOIC — verify the PCB footprint matches the SSOP land pattern, not a standard SOIC. The supplier device package is listed as 56-SSOP, identical to the package/case field. This covers most telecom, networking, and industrial control environments but not extended automotive (125°C) or military. Shipped in tube packaging. For pick-and-place, the tube is a standard anti-static tube; no tape-and-reel option is listed in the spec record. If the line requires reel feed, confirm the alternate order code (SN74LVTH16543DLR) for tape-and-reel packaging.
Active lifecycle — sourcing posture
This part is still in the current product portfolio and supported for new designs. It sits in the 74LVTH series, a BiCMOS family that balances the speed of ABT with the low power of LVT. The 74LVTH series has been in production for over a decade and has no announced end-of-life.