Single-gate buffer for mixed-voltage buses
The Texas Instruments SN74LVC1G125DBVT is a single-bit, non-inverting buffer with a 3-state output, part of the 74LVC low-voltage CMOS logic family. The output delivers 32 mA source and sink symmetrically, enough to drive a handful of CMOS inputs or a short PCB trace without an external line driver. Housed in the SOT-23-5 (SC-74A) footprint, it replaces larger octal buffers when only one signal needs gating.
No level-shifter is needed when bridging a 3.3 V controller to a 5 V peripheral — the buffer's input thresholds track VCC.
3-state output and bus isolation
The output enable (OE) pin puts the output into high-impedance state, letting multiple buffers share a bus without contention. This is the feature that distinguishes a 3-state buffer from a plain line driver — useful in multiplexed address/data buses or shared interrupt lines where the output must disconnect when not selected. The single-gate format means you place exactly one buffer per signal, no wasted gates.
Package and footprint — SOT-23-5
The SN74LVC1G125DBVT ships in the SC-74A / SOT-753 package, which maps to the standard SOT-23-5 footprint. Five pins: VCC, GND, input A, output Y, and output enable (OE). The small body saves board area compared to an SOIC-8 or TSSOP-8, and the surface-mount profile suits automated assembly. MSL level is not stated in this listing, but 74LVC single-gate parts typically carry MSL 1 — verify with the reel label if the part has been in storage.
For a single-gate buffer that crosses multiple voltage domains, this is a low-risk line item to qualify into production.