meerweten:
good i only need about a 400mA thanks
400mA can be too much if the input voltage is high.
Asking about current is the wrong question. You have to calculate how much power the regulator needs to throw away (ie. convert to heat).
An easy way to do the calculation is to put your finger on the regulator then connect the power. If it you have to remove your finger to avoid a blister, you need an external regulator...