Control circuit

The invention relates to a control circuit. A power supply voltage is received to output a control signal to drive electronic equipment, wherein the control circuit comprises a first current limiting unit, a second current limiting unit, a first control unit and a second control unit; when the first current limiting unit permits a current to flow into the first control unit to start the first control unit, the second current limiting unit prevents the current from flowing into the second control unit; and when the second current limiting unit permits the current to flow into the second control unit to start the second control unit, the first current limiting unit prevents the current from flowing into the first control unit, so that, no matter that the voltage supplied to the control circuit by a power supply is positive or negative, the first control unit or the second control unit can output the control signal, and the electronic equipment normally runs.