Power Supply Query

Submitted by Pete on Wed, 07/14/2021 - 16:09

First time post - hello all.

I'm looking for a power supply solution that I assume already exists - I dont think I'm trying to re-invent the wheel but can't find a product?  I'm quite capable of building electronics projects but I don't have the design capability.  This problem seems frustratingly simple but has left me without a resolution.


I have an instrument - normally powered by a 12V car battery.

It outputs very short duration pulses of 1A or 8A (power on for max 20 ms and off for up to 50 ms - full cycle up to 8 minutes - max 20 times in a day)

In order to boost output (up to 16A or 20A (this is the max))  we add another 12V and a 6V battery, thus providing 24V or 30V in total.

I'm looking to take one 12V car battery but have some kind of DC/DC converter(s) that I can hook up to the 12V battery and select the output for either 12V, 24V and 30V - be that 3 seperate converters (in one neat box I can build) or output voltage selectable by changing a resistor value, etc.

The max output from the instrument is 20A at 30V, which is 600W. So I guess the input current to supply that capacity from one 12V battery, in the worst case scenario, would be 50A plus a bit for losses due to inefficiencies.

Any thoughts?  I have Googled a lot to no avail. The units I've found have too high input voltage, not enought power capability, wrong output voltages, etc.

Many thanks


Please state simply.
You need DC DC converter that supports 12V input, Output 12V, 24V, 30V. What is the current rating required in all cases?

  Joined February 12, 2018      696
Monday at 02:11 PM