I'm thinking of using a zener diode to regulate 12 V from a voltage source that produces a max of 24 Volts and about 14 Amps. Would I need a zener diode that has a power rating of 14*12=168 Watts?

 

What current do you need at 12v?

A Zener is a shunt regulator. They are cheap, and useful for small loads, but not very efficient.

 

Linear regulators are one step up from zeners, almost as cheap. I think the part number is 7812.

 

If your load is up to perhaps 40mA, you could use just a Zener and a resistor. Regulation won't be very good.

A 7812 is good for about 1A, but with a 24v supply, you will dissipate 1/2 the power of the load in the regulator itself. You will need a heat sink for a load greater than around 80mA.

Switching regulators are much more efficient, but are more complex.

 

My current can reach up to around 14 amps....

 

The most efficient solution is a buck DC/DC converter.

 

The most efficient solution is a buck DC/DC converter.

Are there any other solutions? I suppose you could design something using a transformer where a buck converter has its inductor, but that fits in pretty much the same mental "box" for me. How else could you provide such a large amount of current?

 

Are there any other solutions? I suppose you could design something using a transformer where a buck converter has its inductor, but that fits in pretty much the same mental "box" for me. How else could you provide such a large amount of current?

You can use a linear regulator but this will be very inefficient due to the significant amount of current. What is more, a big heat sink is needed to dissipate heat fast which occupies large space. For DC to DC voltage level conversions switching regulators are the most efficient until now.

 

You'd be pretty hard-pressed to step down 24v to 12v using a linear regulator; the power dissipation in the regulator would be the same as the dissipation in the load. Not a happy situation.

 

You'd be pretty hard-pressed to step down 24v to 12v using a linear regulator; the power dissipation in the regulator would be the same as the dissipation in the load. Not a happy situation.

It is not a happy situation, but if a resistor is added in series with the regulator the same power will be wasted but the power will go into the resistor instead of the regulator. Leave enough voltage at the input of the regulator for it to regulate ( and consider droop in the 24 v input )

All that said, if you really need 14 amps out for any period of time, some sort of switching regulator is really required.