Stabilized plural output transistor power source device having a plurality of limiting current control circuits

An IC for feeding an electric power to a load circuit which is designed to obtain an output voltage of a predetermined target voltage as an output of an output transistor through voltage drop of a power source voltage by said output transistor, generates an error signal depending on either the difference between said predetermined target voltage and the actual output voltage or a voltage obtained by multiplying a predetermined rate to the predetermined target voltage and a voltage obtained by multiplying the predetermined rate to the actual output voltage, and controls the output current of said output transistor depending on the error signal so as to stabilize the actual output voltage at said predetermined target voltage, comprising:

• n pieces of said output transistors, wherein n is a positive integer equal to 2 or more than 2, each outputting to a common output terminal;
• n pieces of over current detection circuits provided for the n pieces of the respective output transistors and outputting respective detection signals when the output currents flowing through said respective corresponding output transistors exceed predetermined rated current values set for said respective corresponding output transistors;
• and
• n pieces of control circuits provided for the n pieces of the over current detection circuits and when being received the respective corresponding detection signals each limiting the output currents of the respective corresponding output transistors relating to the over current detection circuits from which the detection signals are received to respective values equal to or less than the respective predetermined rated current values, and wherein the grand total of the respective predetermined rated currents of the n pieces of said respective output transistors is fed to said load circuit as a rated out current from the common output terminal.