I am kind of curious about this because for my project I have three power lines (12,5,3V3) but each one needs it own special voltage regulation designed for the current consumption.
I know there are three kind of voltage regulation:
- Voltage divider
- linear regulators
- switching regulators
But none of these seem to care what the input current allows them to draw and "generates" their own limit.
Example of what I mean: I regulate a power adapter Vin with 12V/5A to 5V. My 5V power lines needs about 2A so I put in a small switching regulator like an LCW78. Last but not least I need to power my MCUs which need 3V3 and about 500mA - 1A, so I use a cheap AMS1117 linear regulator for that.
Here is the thing, ESP. With the linear regulator, that surprises me. If I don't use an AMS1117 but a cheaper Chinese 4B2x regulator that only supplys up to 150mA my MCU has a problem.
Why, though? In theory my 5V power lines has enough "power" to support the MCU as well but the regulator stops it.