Single buffer with open-drain output for mixed-voltage buses
The SN74AUP1G07DBVT is a single non-inverting buffer from Texas Instruments' 74AUP series, featuring an open-drain output that pulls low when active and floats high — the pull-up resistor is external, so the output voltage can be set independently of the supply rail, making it a natural fit for level-shifting or wired-OR buses where multiple outputs share a common line.
Housed in a 5-pin SOT-23-5 (SC-74A) package, the footprint is 2.9 mm × 1.6 mm with a 0.95 mm pin pitch — a two-layer board with 0.5 mm traces handles the fan-out without vias. The output sinks 4 mA maximum when low; the open-drain structure means the high-level current is zero, so the pull-up resistor value sets the rise time and the load current — a 10-kΩ pull-up to 3.3 V draws 330 µA when the output is low, well within the sink capability.
Cross-reference note
The SN74LVC1G125YZPR is a 3-state buffer from the 74LVC family with a push-pull output and 32 mA drive, but it requires a separate output-enable pin and does not support wired-OR connections — the open-drain output of the SN74AUP1G07DBVT is the deciding factor for shared-bus applications where multiple drivers must float high without contention.