2.7V threshold supervisor for automotive power rails
The TPS3840PH27DBVRQ1 is a Texas Instruments simple reset/power-on reset IC from the automotive AEC-Q100 series, monitoring a single voltage rail with a 2.7V threshold. It asserts a reset output — active high, push-pull — whenever the monitored supply drops below that threshold, and holds the reset for a typical 619ms timeout after the rail recovers.
619ms timeout — brownout ride-through without nuisance resets
The 619ms typical reset timeout gives the supply rail time to recover from a short brownout or load transient before the system restarts. For a 12V automotive bus that sees cranking dips, that window is wide enough to avoid a reset on a 200ms sag, but short enough that the system doesn't hang dead through a sustained undervoltage.
SOT-23-5 package — footprint and mounting
Housed in the SC-74A / SOT-753 (SOT-23-5) surface-mount package, the part occupies roughly 3 mm × 3 mm of board area. No exposed pad — thermal management is through the package body and copper traces.