Patent ID: 8847574

Claim:
An electrical isolator circuit comprising: an input stage comprising first and second inputs, the input stage being configured to receive an input voltage signal; an output stage comprising first and second outputs electrically connected across a load capacitor; and a DC isolator comprising a first capacitor between said first input and said first output and a second capacitor between said second input and said second output; wherein first and second plates of each of the first, second and load capacitors are defined by conductive layers of a printed circuit board and the dielectric of each of the first, second and load capacitors are defined by a non-conducting part of the printed circuit board, wherein said first, second and load capacitors are defined by four of said conductive layers, all of which at least partially overlap with each other, such that one of said conductive layers defines a first of said plates of said load capacitor and one of said plates of said first capacitor, and another of said conductive layers defines a second of said plates of said load capacitor and one of said plates of said second capacitor.