What this supervisor does for a 5V rail
The TPS3813I50DBVR: This is a single-channel voltage supervisor that monitors a 5V supply rail and holds the reset output active-low until the rail rises above 4.55V and stays there for at least 20ms. The open-drain output lets you wire-OR it with other reset sources on the same pull-up line — handy when a microcontroller needs a clean release after both the 3.3V and 5V rails are stable. The 4.55V threshold is set for a nominal 5V supply; if your rail dips below that during a brownout or hot-plug event, the output pulls low and stays low until the supply recovers and the timeout expires.
Temperature grade and package constraints
The SOT-23-6 package keeps the footprint small (2.9 mm × 1.6 mm typical), but the open-drain output requires an external pull-up resistor; budget a 10 kΩ to 100 kΩ to VDD.
The TPS3813 base number is current, and the I50 grade (industrial, 4.55V threshold) is an active ordering option. ROHS3 compliant; no special MSL concerns for the SOT-23-6 package. The SOT-23-6 package is widely available in tape-and-reel or cut-tape formats. No single-source risk — TI produces this in multiple fabs, and the open-drain supervisor topology is straightforward to second-source if needed.