An integrated circuit based transformer, comprising: a primary winding located in a winding layer, the primary winding having two primary terminals at a first side of the transformer; a secondary winding located in a winding layer, the secondary winding having two secondary terminals at a second side of the transformer, the first and second sides located at different sides of the transformer; and a reference bar located in a reference bar layer, the reference bar having a primary reference bar terminal at the first side of the transformer, and having a secondary reference bar terminal at the second side of the transformer. The reference bar is configured to provide a direct electrical connection between the first reference bar terminal and the second reference bar terminal.