My RPi3B+ is an embedded front end for a scientific instrument. I have an interface PCB with a 3amp 5v regulator, driven by a 48v supply. I monitor the 48v with ADC polled each 100ms, then sudo shutdown at a critical voltage(`40v). I have several seconds depending on how much capacitance I design into the 48v supply. At any time the user can power down or power failures can happen. My questions are : how long do I have until it's safe for the 5v to turn off? Can I detect in software when it's safe? Can I depower the display to stretch the time the 5v lasts? Graham
Asked
Active
Viewed 28 times
