I am looking for a smart way to regulate my input power Vin = 12-24V to a stable Vout = 12V; Imax = 3A- Usual I use the TI Workbench but this time it makes really complex designs. On the Load side there are DC Motors and Sensors - The supervisor wants low noise so I thought about using a Linear Regulator but I read that Vin needs to be at least 1-2V higher than Vout and an LDO doesn't work if the input voltage is already at 12V I would need a boost which would make everything even more complex. There is only 1 Vin and I don't know if the user uses 12 or 24V.
After I regulate it to 12V I would like to use a Buck (TPS56339) for getting it down to 5V and power up an ESP. Further I need to regulate it down to 3V3 to power up some IC's which I would make over a linear from 5V to 3V3 because the current needs to be higher than from the ESP32 3V3 pin.
The only step I am really stuck on is a good way to regulate the first step from 12/24V to 12V. If possible I would like to internally read the voltage level and if it's already on 12V, skip the first regulation. If it's at 24V put it into a linear to get it down to 12V (36W should be doable?).
A good idea how to do that? Thanks!