Power supply help

[burhanmz]

Hello everyone.
I am a freshmen, completing my first year (2nd semester at some university, doing electronic engg). I have been given to make a project of a 0 to12 volts regulated variable power supply, with upto 1~2A current rating.
Can some one help.
Ok i have started using this software (recently bought a copy of multisim 7.0.2 Educator edition) but am not totally familiar with it. i want to know what can i use in place of OP-AMP LM317, LM711 and L7805 IC.i can't find it anywhere in the software. is there something else to do in its place.
Because i thought of making a simple Zener regulated power supply... but i can't use a potentiometer parallel with a zener, as all calculations would change and zener might work for some values and not for others,, and it can't bear max current of 1A, i'm sure.
So i decided on using a OP-AMP LM317T. but i cant get its simulation done without the component. Can someone help... or atleast give some idea of making a this sort of power supply... [remember i need to keep it as simple as possible]

 

[audioguru]

An LM317 is a variable voltage voltage regulator, not an opamp.
Its max rated current is 1.5A but some can go as high as 3.4A.

An LM350 is another variable voltage voltage regulator.
Its max rated current is 3A.

An LM338 is another variable voltage voltage regulator.
Its max rated current is 5A.

They all have a minimum voltage of 1.25V without a negative supply. With a negative supply and a few parts then the output voltage will go to zero volts.

Never mind the old simulation software that has a poor library, use the data from the datasheets. They have the circuit already designed.