Abstract: A two-axis magnetic field sensor includes a substrate, a first sensor having at least one magnetoresistive element formed of GMR material on the substrate has a free layer having an easy axis of effective anisotropy field in a first direction. The first sensor is sensitive to magnetic field components perpendicular to the first direction. A current is caused to flow through the first sensor and variations in the resistivity of the first sensor due to the first magnetic field components are sensed. A second sensor having at least one magnetoresistive element formed of GMR material on the substrate has a free layer having an easy axis of effective anisotropy field in a direction substantially perpendicular to the first direction. The second sensor is sensitive to second magnetic field components perpendicular to its easy axis of effective anisotropy. A current is caused to flow through the second sensor and variations in the resistivity of the second sensor due to second magnetic field components are sensed.

Abstract: An integrated magnetic field sensing device includes at least two magnetoresistive elements which are biased in a first direction by an integral conductor and are sensitive to magnetic field components in a direction perpendicular to the first direction. The sensitivity of the device to a magnetic field is adjustable and is related to the level of the bias current. In a current measuring application, two of the magnetic field sensing devices are mounted on opposite sides of and perpendicular to a conductor carrying a current to be measured. In a portable current measuring apparatus, two of the magnetic field sensors are mounted in a housing that assists in locating the magnetic field sensors relative to the conductor carrying the current to be measured.

Abstract: A method for synchronizing nodes in a network is described that utilizes an interactive convergence technique. The technique utilizes communications protocol IEEE 1394 to broadcast each node's clock value to the other nodes in the network. Each node applies a voting algorithm to the set of broadcasted clock values to determine a voted clock value and each node's clock is set to that voted clock value. When a node's clock value is close in value to another node, those nodes are considered to be synchronized. The set of clock values to be used to determine the voted clock value consists of those nodes that are synchronized. The technique is implemented on hardware separate from the node's hardware and can be implemented on a field programmable gate array.

Abstract: Methods and apparatus for electrostatically pumping fluids without passing the fluids through the electric field of the pump are contemplated. Electrostatic forces are preferably used to move the diaphragms in one direction, while elastic and/or other restorative forces are used to move the diaphragms back to their original un-activated positions. In some embodiments, this may allow fluid to be pumped without passing the fluid between actuating electrodes. This may be particularly useful when the fluids have dielectric, conductive, polar or other qualities that may affect traditional electrostatic pump performance. Pumps having various elementary cells are contemplated, including two-celled pumps disposed within a single chamber and pumps having greater numbers of cells wherein each cell is disposed within a different chamber.

Abstract: Methods for attaching two wafers are presented along with devices resulting from such methods. In one illustrative embodiment, a first wafer is provided having pillars for conducting an electric signal. The wafer also includes an electronic device such as an inductor or capacitor that may in some instances consume relatively large amounts of space. The first wafer is bonded to a second wafer so that a circuit on the second wafer may be electrically connected to the electronic device of the first wafer.

Abstract: An apparatus for electrostatically pumping fluids without passing the fluids through the electric field of the pump is contemplated. Electrostatic forces are preferably used to move the diaphragms in one direction, while elastic and/or other restorative forces are used to move the diaphragms back to their original un-activated positions. In some embodiments, this may allow fluid to be pumped without passing the fluid between actuating electrodes. This may be particularly useful when the fluids have dielectric, conductive, polar or other qualities that may affect traditional electrostatic pump performance. Pumps having various elementary cells are contemplated, including two-celled pumps disposed within a single chamber and pumps having greater numbers of cells wherein each cell is disposed within a different chamber.

Abstract: A threshold control circuit for CMOS transistors wherein the voltage on the body of an n-channel reference transistor is controlled with a feedback circuit to produce a positive voltage on the body and decrease the threshold of the reference transistor to a desired value and the voltage on the body of a p-channel reference transistor is controlled with a feedback circuit to produce a negative voltage on the body and decrease the threshold of the reference transistor to a desired value.

Abstract: A method of manufacturing a microactuator device includes a plurality of generally parallel thin flexible sheets bonded together in a predetermined pattern to form an array of unit cells. Preferably, each of the sheets has only a single electrode layer located on one side of the sheet. Pairs of such sheets are then bonded together at spaced bonding locations with the electrode layers facing one another. Several sets of such sheet pairs can then be bonded together to form a microactuator device.

Abstract: A position determining apparatus including a magnet that is attached to a movable member which moves along a defined path of finite length. An array of distributed bridge sensors are located adjacent to the predefined path. The distributed bridge sensors each have one or more magneto-resistive elements positioned at a first location along the defined path of the magnet, and one or more other magneto-resistive elements positioned at a second location along the defined path. The magneto-resistive elements at the first location experience a different magnetic field component than those at the second location. The distributed bridge sensors produce an increased linear range relative to non-distributed bridge sensors of the prior art.

Abstract: A global positioning system for use with a plurality of transmitting satellites is disclosed wherein a full position solution is obtained from a number N of satellite transmissions and a plurality of sub-solutions each based on a different number (N−1) of satellite transmissions are obtained to determine if a satellite is faulty. A plurality of sub-sub-solutions is then obtained based on a different combination of N−2 satellites with each combination containing the satellites of different sub-solutions and excluding one other satellite in addition. An examination of the sub-sub-solutions provides an indication of which one of the satellites is the failed satellite.