Cot switching regulator control mode being one kind of a timer

The present invention discloses a switching regulator control mode being one kind of the COT timer, comprises: a first transistor, a second transistor, a third transistor, a fourth transistor, a first operational amplifier, a first comparator, the first a capacitive reactance element, a first resistive element and a first switching unit, characterized in that, further comprising: a second switching unit, a third switching unit and the first inverter. Timer switching frequency of the present invention depends only on the size of the resistance and capacitance and capacitive reactance means resistance unit, in which the same conditions, the switching frequency is constant, thereby overcoming the conventional operating frequency of the control circuit receiving the output of COT problems affecting the voltage to achieve the constant operating frequency in CCM state. Timer present invention is suitable for various switching regulator, the control system can be simplified adjuster, improve the conversion efficiency.