2.93 V threshold — where it catches the brown-out
The TPS3619-33DGKR is a battery-backup supervisor IC from Texas Instruments that monitors a single 3.3 V supply rail and asserts a reset when the voltage drops below 2.93 V. The 60 ms minimum reset timeout gives most MCUs and SoCs enough time to complete an orderly shutdown or hold in reset during a glitch. The active-low, push-pull output drives the processor's reset pin directly without an external pull-up.
Package and footprint — 8-VSSOP layout notes
The 0.50 mm pin pitch is manageable on a two-layer board if the bypass cap and the battery-backup capacitor sit close to the supply and backup pins. Keep the trace from the reset output to the processor under 50 mm to avoid noise coupling that could stretch the reset pulse.