What this bus switch does on your board
The QS3VH253PAG8 is a Renesas 3VH-series Bus Switch — a 2 x 4:1 multiplexer/demultiplexer that routes digital signals without adding propagation delay. It switches two independent 4:1 paths, each controlled by its own select line, making it a direct fit for shared data buses, memory bank selection, or peripheral muxing in 2.5V or 3.3V logic domains.
The supply range of 2.3V to 3.6V covers both 2.5V and 3.3V rails without an external regulator — a single-supply part that simplifies power distribution. Because it's a single-supply device, the switch's on-resistance stays flat across the voltage range, so signal attenuation is predictable regardless of whether your rail is 2.5V or 3.3V.
Package and footprint — 16-TSSOP
Housed in a 16-TSSOP package (4.40 mm width, 0.173" body), the QS3VH253PAG8 is a surface-mount part supplied on Tape & Reel (TR) or Cut Tape (CT).