current booster

Hi all,
I am looking for a way to make a voltage regulator like this

Vin==========> regulator =======> Vout
power supply===>

Vin can be any positive range, for example 0V to 12V, but current is limited to only about 2mA or so, because it is coming from a DAC. Power supply can be any resonable value, probably about 20V, and Vout needs to be from 0V to 12V with current up to 500mA, as to power a high voltage amplifier.

Use an LT3080 regulator Linear Technology - LT3080 - Adjustable 1.1A Single Resistor Low Dropout Regulator in the TO-220 package attached to appropriate heatsink. (500mA @ 20V input and 0V output will give a maximum dissipation in the regulator of 10W)

Feed the DAC output to the SET pin.

Connect the Supply to the IN and Vcontrol pins.

The regulator OUT pin voltage will closely equal (within about 10mV) the SET pin voltage.

Make sure you add the recommended input and output decoupling capacitors near the regulator pins.

NOTE: To minimize the regulator power dissipation you can run the power supply voltage as low as 2V above the output voltage (14V for 12V out).