Abstract: A charge pump circuit is provided comprising a MOS capacitor, a capacitor ("series capacitor") connected in series, a MOSFET diode, and a voltage clamp connected to the common node of the MOS capacitor and the series capacitor. A number of these charge pump circuits may be cascaded to form a multi-stage charge pump circuit. Each charge pump circuit may attain output voltage higher than the oxide breakdown voltage of each individual MOS capacitor. This charge pump circuit can also operate under low voltage power supply conditions.

Abstract: A linear displacement transducer includes a first elongated magnetizable member having first and second pole pieces which extend parallel with each other over the full length of said first member and which are of substantially constant width along their length. A first winding is wound around part but not all of said first member, a second winding is wound around the full length of the first member. A second elongated member having at least a part which is shorter than said first elongate member is movable linearly relative to the first member in a direction parallel with the longitudinal axis of the first member, such that a substantially constant gap is maintained between the members, to vary the magnetic coupling between the first and second windings when an a.c. signal is applied, in use, to one of the windings.