Dual-rail supervisor for mixed-voltage boards
The Texas Instruments TPS3306-15DG4 is a multi-voltage supervisor that monitors two independent supply rails with thresholds of 1.4V and 2.93V. It asserts an active-low reset when either rail drops below its threshold, with a minimum reset timeout of 70ms. This part is designed for systems that need to sequence or protect both a core logic rail (2.93V) and a lower I/O or memory rail (1.4V) from a single supervisor IC.
Open-drain output and reset behaviour
The reset output is open-drain, active-low, so it can be pulled up to any voltage within the absolute maximum rating of the output transistor — typically up to 6 V. This makes it straightforward to interface with 1.8 V, 2.5 V, or 3.3 V logic domains without a level shifter. The open-drain configuration also allows multiple supervisors to share a common reset line in a wired-OR arrangement.
Housed in an 8-pin SOIC package (0.154-inch body width, 3.90 mm), surface-mount. No special moisture-sensitivity handling beyond standard MSL-1 for SOIC is expected, but verify the date code lot if the part has been in long-term storage.