Abstract: An inductor circuit includes an inductor and an RC circuit. The RC circuit includes a resistor and a capacitor. The resistor and the capacitor are coupled in series. A first terminal of the inductor is coupled to the resistor through a first contact. The resistor is coupled to the capacitor through a second contact. The capacitor is coupled to a second terminal of the inductor through a third contact.

Abstract: A surge suppression circuit includes a metal oxide semiconductor field effect transistor (MOSFET), a first resistor, a first capacitor, and a passive component. The MOSFET, the first resistor, and the first capacitor are integrated to form an integrated circuit. The first capacitor and the first resistor are connected in series between a drain and a source of the MOSFET; the passive component is disposed outside of a package of the integrated circuit, the passive component is electronically connected between the first resistor and the first capacitor, or is electronically connected in parallel with one of the first resistor and the first capacitor.

Abstract: A printed circuit board (PCB) includes a base, copper foils, an insulating layer, and metallic foils. The copper foils are disposed on the base. The insulating layer is coated on the copper foils. The metallic foils are layered on the insulating layer. The copper foils and the metallic foils connect a first electrical element to a second electrical element.