Abstract: A compensation method and apparatus for enhancing single-ended to differential conversion includes a compensation network that is coupled between the single-ended voltage input and the bias terminal of a differential stage. The compensation network has an impedance substantially equal to the impedance presented by the bias circuit used to bias the differential stage. Accordingly, the compensation network provides a current that substantially cancels the signal tail current supplied to the bias terminal of the differential stage, resulting in a balanced differential output. The compensation network may be AC coupled from the single-ended voltage input to the bias terminal in order to preserve the original DC operating condition. The compensation network may be chosen to provide more cancelling current at higher operating frequencies. Additionally, the compensation network can be configured to match a bias circuit built from resistors, transistors, current mirrors, or the like.

Abstract: Integrated capacitors provide more than one capacitor on a single dielectric substrate. A dielectric substrate has a conductive backplane on one side and two or more conductive capacitor plates on the opposite side. The integrated capacitors may be mounted on a shield wall which has a through hole so that one capacitor is connected to the shield wall and another forms a coupling capacitor via the hole between two stages on opposite sides of the shield wall.