Abstract: A microelectromechanical system (MEMS) analog isolator may be created in which an actuator such as an electrostatic motor drives a beam against an opposing force set, for example, by another electrostatic motor. Motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: A microelectromechanical system (MEMS) analog isolator may be created in which an actuator such as an electrostatic motor drives a beam against an opposing force set, for example, by another electrostatic motor. Motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: Microelectricalmechanical systems (MEMS) manufactured on a microscopic scale using integrated circuit techniques may be used to measure a variety of parameters using electrical signals generated by the movement of small beams. Inertial noise may be canceled by the duplication of the beam structure for sensing of the acceleration to be subtracted from a similar beam structure used to measure the parameter of interest.

Abstract: An isolated-ADC and a method for providing isolated analog-to-digital conversion are disclosed. The isolated-ADC includes a microelectromechanical system (MEMS), a comparator, and a digital-to-analog converter (DAC). The MEMS includes a beam element supported from a substrate for movement with respect to an axis, first and second actuators and a sensor. The first and second actuators are capable of exerting respective forces upon the beam element causing the beam element to move in response to analog input and feedback signals, respectively. The sensor detects changes in position of the beam element and produces a position signal indicative thereof. The comparator generates a digital signal based upon a comparison of the position signal with a reference value. Based on the digital signal, the DAC generates the feedback signal, and the isolated-ADC produces a digital output signal.

Abstract: A microelectricalmechanical system (MEMS) digital isolator may be created in which an actuator such as an electrostatic motor drives a beam against a predefined force set, for example, by another electrostatic motor. When the threshold of the opposing force is overcome, motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: An isolated-ADC and a method for providing isolated analog-to-digital conversion are disclosed. The isolated-ADC includes a microelectromechanical system (MEMS), a comparator, and a digital-to-analog converter (DAC). The MEMS includes a beam element supported from a substrate for movement with respect to an axis, first and second actuators and a sensor. The first and second actuators are capable of exerting respective forces upon the beam element causing the beam element to move in response to analog input and feedback signals, respectively. The sensor detects changes in position of the beam element and produces a position signal indicative thereof. The comparator generates a digital signal based upon a comparison of the position signal with a reference value. Based on the digital signal, the DAC generates the feedback signal, and the isolated-ADC produces a digital output signal.

Abstract: A capacitance comparison circuit determines the relative value of two capacitors, such as may be sensor elements, by monitoring voltage changes caused by charge redistribution between the capacitors when they are series connected and then connected alternately in a first and second polarity across a voltage. The direction of change of voltage at the junction of the capacitors with respect to the switching of polarity of their connection precisely reveals which capacitor is larger. Disconnecting the voltage monitor during the switching reduces switching induced errors.

Abstract: A microelectricalmechanical system (MEMS) digital isolator may be created in which an actuator such as an electrostatic motor drives a beam against a predefined force set, for example, by another electrostatic motor. When the threshold of the opposing force is overcome, motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: Microelectricalmechanical systems (MEMS) manufactured on a microscopic scale using integrated circuit techniques may be used to measure a variety of parameters using electrical signals generated by the movement of small beams. Inertial noise may be canceled by the duplication of the beam structure for sensing of the acceleration to be subtracted from a similar beam structure used to measure the parameter of interest.

Abstract: A circuit can be configured to process signals from either a resolver or an encoder to derive an indication of the sensed angular position. (1) When the circuit is configured for an encoder, the output from the encoder is periodically sampled. The phase relationship of the encoder input signals controls a counter. The output of the counter is periodically sampled to provide the position indication. (2) In the resolver configuration, the counter is rest at regular intervals. An apparatus detects zero crossings from the resolver signal and in response thereto samples the counter output to provide a measurement of the time interval between the counter reset and the zero crossing. The magnitude of the time interval corresponds to the phase angle of the resolver signal and hence to the angular position.

Abstract: A programmable controller is formed by connecting separate functional modules to a common backplane bus. A bus arbitration scheme and a message handling technique are disclosed to tightly couple the functional modules together to form an efficient programmable controller. A number of improvements to the CPU module and I/O scanner module are disclosed to further improve the performance of the resulting system.

Abstract: A programmable controller includes a processor formed around a pair of four-bit bipolar microprocessors. A control program formed by selected macroinstructions is stored in a random access memory and it is executed by sequentially mapping each macroinstruction operation code into a corresponding microroutine which is stored in a read-only memory. Some macroinstructions include operand addresses of a line in an I/O image and data table portion of the random access memory, and one macroinstruction (ADX) expands this operand address to enable the I/O image and data table to be expanded in size. A timer macroinstruction is executed in part by reading the state of a counter which is driven by a real time clock, and arithmetic functions are performed with the use of a decimal adjust accumulator.

Abstract: A numerical control system processor is disclosed which stores and executes a control program of the type found in programmable controllers. A number of editing features are provided which allow changes to be made in the control program including insert and delete functions which result in the shifting of control program instructions. A jump table is provided to store memory addresses of jump instruction targets and this table is updated by special instructions within the control program after editing functions are performed. Jump instructions refer to this table when executed to obtain their target memory address.

Abstract: A programmable controller includes four remotely located input/output interface racks which are connected by cables to an I/O scanner circuit which is centrally located with the controller processor and memory. Input and output data is serially transmitted between the I/O scanner circuit and the interface racks, and fault processors are located in both the I/O scanner circuit and the interface racks to monitor the operation. The fault processors include fault tolerant detector circuits which ignore erroneous transmissions caused by industrial noise, but which initiate a shutdown process when malfunctions occur. The shutdown process is controlled by a programmable disabling circuit which is responsive to program instructions stored in the controller memory to allow independent, quasi-independent, or dependent operation of the machines connected to each of the four interface racks.