Patent ID: 8704504

Claim:
A power supply circuit comprising: a control circuit comprising: a detection circuit including a first reference voltage generation circuit, a second reference voltage generation circuit, and an input signal adjustment circuit; an error amplifier circuit; a pulse width modulation driver; a triangle-wave generation circuit; and a capacitor, an amplifier circuit electrically connected to the control circuit that outputs an output voltage; and a divider circuit that is electrically connected to the control circuit and the amplifier circuit and inputs a voltage obtained by dividing the output voltage as a feedback voltage to the second reference voltage generation circuit, wherein the input signal adjustment circuit comprises a first operational amplifier having a first non-inverting input terminal electrically connected to a first resistor and a second resistor and a first inverting input terminal electrically connected to a third resistor and a fourth resistor, and wherein the first reference voltage generation circuit comprises a second operational amplifier having a second non-inverting input terminal electrically connected to a fifth resistor and a first diode and a second inverting input terminal electrically connected to a sixth resistor, the sixth resistor is electrically connected to a second diode, and the first diode and the second diode are applied with a power source voltage, and wherein the second reference voltage generation circuit comprises a third operational amplifier having a third non-inverting input terminal electrically connected to a seventh resistor and a third diode and a third inverting input terminal electrically connected to an eighth resistor, the eighth resistor is electrically connected to a fourth diode, and the third diode and the fourth diode are applied with the feedback voltage.