I had read in TCA0732 datasheet that its current supply can't be greater than some decades of mA (+14mA for +15V voltage supply) but it can provide 1A of current how can that be possible, the same thing for OP2544 max supply current is 30mA and it can provide 2A of output current these amplifiers amplify voltage and also current where the power comes from ?? Datasheets:http://www.onsemi.com/pub_link/Collateral/TCA0372-D.PDF
The supply current is what the op amp(s) require in order to operate. If you measure all the current going from the positive supply pin to the negative supply pin you will get a current within that value. The output current, on the other hand, is between the supply pins and the output. This is not consumed by the device but rather is delivered to the load.