Three-rail supervisor for multi-voltage boards
The MAX6720UTTGD3+T is a multi-voltage supervisor from Analog Devices that monitors three independent supply rails — 1.11 V, 3.075 V, and an adjustable threshold — and asserts an active-low, push-pull reset output whenever any monitored voltage drops below its threshold.
Threshold selection and reset timing
The fixed thresholds at 1.11 V and 3.075 V cover common core and I/O rails, while the adjustable input lets you set a third threshold with an external resistor divider — useful for a 1.8 V or 2.5 V memory supply. The 140 ms minimum reset timeout provides a predictable power-on delay; if your processor requires a longer reset pulse, an external capacitor on the adjustable delay pin (where applicable) extends it.