Current regulating circuit and power supply management circuit including the same

A current regulating circuit, comprising:

• a first transistor used as an input, which is installed on a path through which a current to be regulated flows;
• a second transistor used as an output, which is connected to the first transistor to form a current mirror circuit;
• a resistor installed on a path of a current flowing through the second transistor;
• a stabilizing circuit configured to match an operating point of the second transistor with an operating point of the first transistor;
• a transistor controller configured to regulate a voltage to be supplied to a control terminal of the first transistor according to a current detection signal that corresponds to a voltage drop across the resistor;
• and
• a forced-off circuit installed separately from the transistor controller and configured to turn off the first transistor if the current detection signal exceeds a predetermined threshold value,
• wherein the first transistor includes a plurality of transistor elements connected in parallel and at least one of the plurality of transistor elements is configured to be switchable between an effective mode and an ineffective mode,
• wherein each of the at least one of the plurality of transistor elements is controlled to be in the effective mode or the ineffective mode according to a range of the current to be regulated, and
• wherein the forced-off circuit includes:
• a voltage comparator configured to compare the current detection signal with the predetermined threshold value and generate an off signal if the current detection signal exceeds the predetermined threshold value;
• and
• a third transistor installed between one end of the first transistor and the control terminal of the first transistor and configured to be turned on in response to the off signal.