A control circuit for an AC-DC power converter includes a junction field effect transistor (JFET), a first resistor, a second resistor, and a third resistor. The JFET includes a substrate, a drain, a source, a gate, a first oxide layer, and a second oxide layer. The first oxide layer is attached to a region located between the drain and the gate of the JFET, and the second oxide layer is not attached to a region located between the drain and the gate of the JFET. The first resistor is positioned on the first oxide layer, and the second resistor and the third resistor are positioned on the second oxide layer. When the JFET and the first resistor receive an input power signal, the first, the second, and the third resistors divide the input power signal, and prevent from the breakdown of the first oxide layer and the second oxide layer.