Roland Andrag wrote:

> current - Basically I need to supply a circuit drawing around 3 to 5 A at 5
> V from a 24 V supply.

Take a look at the Linear Technology LT1074/1076
parts.  These are switching regulators that work
well in this type of application.

With a linear regulator you'll have about 100
Watts of heat to dissipate to get 25 Watts of
useful power.

Mark Walsh