24 volt regulator

 

Hello. I want  to build a simple DC voltage regulator circuit. I don't
care about ripple because the voltage is from batteries. THe normal
voltage is 24 but sometimes the voltage goes high at 28. The idea is too
make a circuit that lets the voltage pass when i have 24 volts and to
regulate them to 24 when i have 28.


Any help?

 

How about a 24v Zener Diode
Manufacturers:
http://www.interfacebus.com/diode.html

 

You could look into "low dropout regulators" which are linear regulators
designed to operate with a minimum voltage between the input and output of
the regulator(across the series pass transistor).  I'm not sure what the
minimum may be...possibly as low as 0.1V which might be ok for you're
application.  Check out
http://www.national.com/AU/design/0,4706,1_0_,00.html

-----------------------------------------------
Steve M - www.circuithut.com - hobby site

 

kostas wrote:

You don't say how much current you need.

You could use the combination of a linear regulator and a relay. Switch
in the relay when the voltage gets down below the dropout.

There are buck regulators that could be used to get you down within a
volt or so.

You could also use a shunt regulator, but that would drain your battery
pretty quickly. A zener diode across the power rails is a form of shunt
regulator.

--
Regards,
   Robert Monsen

"Your Highness, I have no need of this hypothesis."
     - Pierre Laplace (1749-1827), to Napoleon,
        on why his works on celestial mechanics make no mention of God.