Supply voltage and temperature — mixed-voltage and industrial deployment
The SN74AHC540PW: Output drive is 8mA sink and 8mA source — enough to switch a standard logic input or a low-power LED indicator, but not a relay coil. The 3-state outputs let multiple devices share a bus; the OE pin pulls the outputs to high-impedance when asserted.
20-TSSOP package — board-fit and reflow considerations
Housed in a 20-TSSOP (0.173", 4.40mm width), the part sits on a 0.65mm pitch — standard for TSSOP, no exotic footprint. The surface-mount body reflows on a standard lead-free profile; the tube packaging means it ships in a rigid anti-static tube, not tape-and-reel, so your pick-and-place feeder needs a tube feeder or you transfer to a tape pocket. ROHS3 compliant — no exemptions for restricted substances; the part passes the European RoHS directive without a compliance gap.