I am working on a project that uses 3 voltage regulators from a 12V input.
INPUT 12V >>[8V reg]>> 8V >>[5V reg]>> 5V >>[3.3V reg]>> 3.3V
I am wondering if is it safe to use an external power supply and apply 5V directly at the output of the 5V regulator to test the 3.3V regulator.
The same would go for the 5V regulator. I would apply 8V at the output of the 8V regulator while leaving its input open.
Is this method safe? Is it safe in general to apply power at the output of a voltage regulator without feeding its input?
Thank you in advance!