Voltage Booster to protect electronics from auto shutdown

Hi everyone and thanks in advance for your advice.

Problem statement
In the marine environment sensitive electronics such as radios and navigation equipment auto shut down if the voltage drops below a certain point.
On small vessels where the start battery is also the power supply for electronics and winches you can often get a momentary drop in voltage that shuts down or restarts electronics.

Proposed solution
I am looking to design a power regulator that can up power from between 8 volts DC to 12.2 to 13.8 volts DC.
It would be good if it had battery backup capability but this is not necessary in the initial model

Is there already a device on this site? I could only find 5v ones for Arduino etc.


Hi Dan,

You could do that. Or you could just install a big fat capacitor (or capacitors in parallel) and a diode, like this:
http://tinyurl.com/yajo9j96 (Link to falstad’s circuit sim, click the starter switch to close it, as if cranking the engine).

You could even just swap the capacitor for a small lead acid battery. You just need to make sure your diode can handle the max current draw of your electronics and can handle the inrush current once the alternator kicks in.

Core don’t have any particularly high current diodes (highest I could find was If = 3A in a diode pack). Here’s one that can handle 5A continuously: https://au.mouser.com/ProductDetail/Kyocera-Electronic-Components/FSF05A20?qs=h6V4JsTaLXfbT8jjRjVZFg%3D%3D

And here’s the datasheet: https://au.mouser.com/datasheet/2/909/FSF05A20-file-1588999.pdf

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Used to be illegal to run communications radio from starting battery. Not a good idea anyway if radio for emergency use as well as normal comms which is quite common.
Cheers Bob

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Follow up: Another down side to running everything from the starting battery. If your small vessels stationary for some time and your electronic etc accessories are in fairly heavy use there is a good chance you will not have enough battery to start your motive power. That is the greater reason for the low voltage shut down. SO YOU DON’T DRAIN THE BATTERY BELOW A SAFE STARTING THRESHOLD. Nothing to do with protecting the electronics. Incidentally my car has a similar system.
Cheers once again Bob