Quad 3-state buffer with wide supply tolerance
The SN74AHC125RGYR is a quad non-inverting buffer with independent 3-state outputs, one per element, from Texas Instruments' 74AHC family. Each of the four buffers drives up to 8 mA source or sink at the output, and the 3-state control lets you isolate the bus when the output is not needed — the classic signal-routing trick for shared data lines.
What the 8 mA output drive means on the bench
8 mA per channel is enough to light a standard LED (with a series resistor), drive the input of another CMOS gate, or switch a small MOSFET gate at moderate speed. It will not drive a relay coil directly — that needs a transistor or a driver IC. The 3-state high-impedance state (Hi-Z) on each output lets multiple buffers share a bus line; the one with its output enable pulled low drives the line, the rest float. The 14-VQFN package (3.5 mm × 3.5 mm) with exposed thermal pad needs a PCB land pattern that ties the pad to a ground plane for heat sinking. The pad is not electrically connected internally, but a thermal via array under it keeps the junction temperature down when all four outputs are sourcing simultaneously.
Active production and compliance status
The tape-and-reel packaging is the standard delivery for this QFN package; cut-tape quantities are also available for prototype or low-volume builds.