What the 2.93V threshold and active-low output mean for your rail
The MAX821SUS+T: When the monitored supply drops below that threshold, the active-low output (RESET) pulls low — it asserts the reset signal to the processor or logic, holding it in reset until the rail recovers and the adjustable/selectable timeout elapses. The push-pull, totem-pole output structure means you do not need an external pull-up resistor — the output drives high when the rail is good and low when it is not. That saves one component per supervisor and keeps the layout tight on a 4-pin SOT-143-4 package.
Temperature grade and environment
The 125°C upper limit covers hot enclosures, motor-drive cabinets, and under-hood automotive environments without needing a derating step at the system level.