Power Supply Query

Pete's picture


Joined: Jul 14, 2021

Replies: 0
Power Supply Query
July 14, 2021 - 4:09pm

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


Sourav Gupta's picture


Joined: Feb 12, 2018

Replies: 628

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?