The MAX6421XS44+T: This is a single-voltage supervisor with a reset threshold of 4.375V. It monitors a 5V nominal supply and asserts a reset when the rail drops below that level. That saves one component per supervisor on the board.
Industrial temperature grade and tiny package
The SC-70-4 package (also known as SC-82A, SOT-343) measures roughly 2.0 mm × 1.25 mm — it fits in space-constrained designs like portable instruments or sensor modules. The reset timeout is adjustable or selectable via an external capacitor — the datasheet gives the formula for the delay period. That flexibility lets you tune the reset hold time to match the power-up settling of the rest of the system.
Compliance and sourcing
ROHS3 compliant — no restricted substances under the current EU directive. Surface-mount, supplied in strip packaging (likely tape-and-reel for pick-and-place).