They're a brilian solution for all your quick power needs, and like said: They come in a great variety of voltages and currents. When using them, just obey these simple rules:
<ul><li>Never let the voltage on the output exceed the voltage in the input by more that 1 volt. This may seem unlikely, but it frequently occurs when you're using large output capacities and the regulator will die for sure. Just add a diode between output and input to prevent this situation.</li><li>Make sure your input voltage is at least 2 volts higher that the required output voltage. It needs this bandwith to regulate properly.</li><li>Use two tantallum capacitors of about 100nF each between input/ground and output/ground to reduce regulation noise. Keep them as close to the regulator as possible (short leads).</li><li>Use a capacitor on the input (behind the rectifier) large enough to keep the dips on the ripple above the 2 volts as mentioned in point 2, even under maximum load.</li><li>Use a capacitor on the output of about half of the capacity on the input.</li><li>Cool well.</li></ul>
Good luck!
