Patent ID: 8878330

Claim:
An integrated circuit, comprising: a substrate comprising a semiconductor having a first conductivity type; field oxide formed at a surface of said substrate; and a voltage divider, including: an upper resistor located over said field oxide and disposed around a central opening in said field oxide, said upper resistor having an input node adjacent to said central opening in said field oxide and a sense node at an outer edge of said upper resistor; a drift layer located in said substrate under said upper resistor and said central opening in said field oxide, said drift layer having a second conductivity type opposite from said first conductivity type; an input terminal electrically coupled to said input node of said upper resistor and electrically coupled to said drift layer through said central opening in said field oxide; a sense terminal electrically coupled to said sense node of said upper resistor; and a lower resistor electrically coupled to said sense terminal at one end of said lower resistor and to a reference node at an opposite end of said lower resistor.