Two-rail supervisor with push-pull resets
The TPS3305-25DGN from Texas Instruments is a multi-voltage supervisor that monitors two independent supply rails with threshold voltages of 2.25V and 2.93V. It provides both active-high and active-low reset outputs in a push-pull, totem-pole configuration — no external pull-up resistor needed on either output. The 140ms minimum reset timeout holds the system in reset long enough for the core supply to stabilise after a fault clears.
Threshold selection and supply-rail pairing
The 2.25V threshold is set for monitoring a 2.5V rail (typical tolerance ~10%), while the 2.93V threshold suits a 3.3V rail. This pairing is common in mixed-voltage designs where a core logic supply and an I/O or peripheral supply both need supervision.
Housed in an 8-HVSSOP with an exposed pad (the DGN suffix), this package improves thermal dissipation compared to a standard MSOP. The 0.118-inch body width (3.00 mm) fits tight board layouts, but the pad adds a thermal via requirement under the part.
For new designs this means no forced redesign cycle from obsolescence in the near term.