This application note describes the functions and features of STMicroelectronics' supervisor circuits, as well as the combinations of different models. These supervisor circuits effectively reduce the risk of system failure, ensure the safe operation of the system, and are cost-effective.
This document explains the main functions of STMicroelectronics Supervisor circuits, such as Power-On Reset (POR), Low Voltage Detect (LVD), and Watchdog Timer. It details how these circuits minimize system failure risks caused by voltage drops, glitches, or software loops.
| Minimum Reset Pulse Width (trec) | 140 ms |
|---|---|
| Manual Reset Glitch Immunity | 100 ns |
| MR Pulse Width Minimum | 150 ns |
| MR to RST Output Delay Maximum | 250 ns |
The minimum pulse width required is 140 ms to ensure the clock is stabilized and registers are set to default values.
RC circuits are considered unsafe and unreliable because they do not guarantee a minimum reset pulse width and may fail to handle narrow glitches correctly.
The Reset output is asserted to minimize the risk of system failure during brownouts or voltage drops.