how can i convert one 24v dc output into two 12v dc outputs?

i am making a psu for my cctv system. i have a fairly new psu from a fire alarm panel which has battery terminals so it can still supply power even if the mains is out.
my cameras can run on about 9-24v but my DVR needs exactly 12v 5a.
The most logical thing to do i guess is convert the 24v output from the psu into 12v that i can then fuse off to go to different cameras and the dvr.
trouble is i don't know how to. i thought of a voltage divider but it turns out they are bad if using more than a couple of Milli amps.
would a voltage regulator do it?
i'm abit stuck here so any help at all would be brilliant. thanks - luke

silveren6 years ago
Hello!

The best way to lower a voltage in DC, without signifiant loss, is to use
a Buck Converter.
So in your case, the latter must work on a duty cycle of 0.5 (=12V/24V).

However, its disadvantage is that you get an oscillating output voltage and current, so you have to get an inductor having a high inductance for reducing such oscillations.

i hope this will help you.