Abstract: A redundant sensor includes at least two sensing elements. The redundant sensor includes methods and apparatus for time-stamping and combining data from the sensing elements. A method of use and additional embodiments are disclosed.

Abstract: A remote resource can be configured to control connectivity of the power generator modules in a string. For example, a respective power generator module can include a current sense circuit that monitors for presence of communication signal. The power generator module can monitor for a presence of a remotely generated control signal over power line that is used by the respective power generator module to convey power to the external load. If the control signal is present on the power line, as generated by the remote resource, the control circuit in the respective power generator module activates the switch to an ON state such that respective activated power generator module is connected in series with the other activated power generator modules. If no keep-alive control signal is detected within a timeout period, the controller deactivates the respective power generator module.

Abstract: Signal conditioning of multiple sense elements is shown for providing information to a system requiring high accuracy and robust fault coverage. A first signal conditioning ASIC (10) pre-conditions the sense element data and a second system control ASIC (14) mathematically solves predetermined compensation relations based on the output of ASIC (10) and stored compensation data to fully condition the sensor output signal(s). The sense elements (1–6) are each formed by two half bridges whose inputs are pre-conditioned by separate, identical signal conditioning paths to provide highly accurate sense and diagnostic information.

Abstract: A multi-channel pressure sensor module (10) for integration in a hydraulic/electrical control unit of a vehicular braking system is shown. A body or manifold (16) mounts a plurality of strain gauge sense element assemblies (12) each having a port for connection to a fluid pressure source to be monitored. An electronic module assembly (14) has a contact printed circuit board (24) and a sense element printed circuit board (22) sandwiching a spacer/support member (20) and electrically coupled together by a flexible circuit board (26). The spacer/support member (20) is formed with pockets (20e, 20f) for receipt of discrete electronic components and to provide access to wire bond pads (22c) and sense element openings (22b). First and second sets of guide posts (20c, 20d) extend from the spacer/support member for alignment of the circuit boards as well as the electronic module assembly on the base.

Abstract: An ASIC (14, 14′, 14″) conditions two independent outputs (VINM, VINP) of a full Wheatstone piezoresistive bridge (12) in separate conditioning paths. Each path is provided with a bridge supply voltage (VHB1, VHB2) which can serve as a temperature related input signal to respective offset and gain compensation control circuits. The half bridge outputs are inputted to respective amplifiers (U1, U2) along with a selected percentage of the temperature dependent bridge supply voltage. The outputs of the amplifiers provide a signal proportional to respective half bridge output voltage. In one embodiment, the output of the amplifier (U2) in one conditioning path of one half bridge is connected to the input of an amplifier (U4) in the other conditioning path to provide a signal in the one path proportional to the Wheatstone bridge differential output voltage and in the other path a signal proportional to the Wheatstone half bridge output voltage.

Abstract: A port fitting (102) is formed with a closed, pedestal end forming a diaphragm (102a) on which a strain gauge sensor is mounted. A support member (106) is received on the pedestal end and is formed with a flat end wall (106a) having an aperture (106d) aligned with the sensor. A circuit assembly (108) is bonded to the flat end wall and the sensor wire bonded to the electronic circuit. A cover member (114) placed on the support member, is provided with a cavity for a metal shield member (118) fitted inside the cover member before assembly. The shield member is formed with spring members (118b) extending outside the perimeter of the cover member. The cover member is formed with circular cavities (114d) extending in an axial direction to provide seating for contact spring members (117), making electronic contact to the sensor electronics and protruding beyond the body of the cover member. The cover member is also fitted with a circular elastomer gasket member (116), providing an environmental seal.

Abstract: An ASIC (14, 14′, 14″) conditions two independent outputs (VINM, VINP) of a full Wheatstone piezoresistive bridge (12) in separate conditioning paths. Each path is provided with a bridge supply voltage (VHB1, VHB2) which can serve as a temperature related input signal to respective offset and gain compensation control circuits. The half bridge outputs are inputted to respective amplifiers (U1, U2) along with a selected percentage of the temperature dependent bridge supply voltage. The outputs of the amplifiers provide a signal proportional to respective half bridge output voltage. In one embodiment, the output of the amplifier (U2) in one conditioning path of one half bridge is connected to the input of an amplifier (U4) in the other conditioning path to provide a signal in the one path proportional to the Wheatstone bridge differential output voltage and in the other path a signal proportional to the Wheatstone half bridge output voltage.

Abstract: An application specific integrated circuit or ASIC (MSC) is connected to a plurality of bridge type sense elements (1-6) for analog multiplexing (10a, 10b, 10c) the outputs from a selected sense element to a common signal conditioning path (10f). The bridge type sense elements are biased through an electronically programmable resistor (10d1) to derive a temperature signal. The signal conditioning path provides electronically programmable correction for offset and gain proportional to the sensed condition, e.g., fluid pressure. Complete sensor characterization data provided at the time of manufacture is stored in non-volatile memory (10h) which is downloaded to a host controller (12) on command. The ASIC also includes diagnostic test bridges (BR1, BR2) for diagnosing ASIC faults and a signal diagnostic path (10m) for diagnosing sense element and sense element connection faults.

Abstract: A full Wheatstone bridge sensor has conditioning electronics of an ASIC connected thereto. Two independently controlled diagnostic switches (S1, S2) in the ASIC are commonly connected to one of the bridge output nodes. The first diagnostic switch connects first resistor between the bridge output node and bridge supply voltage and the second diagnostic switch connects a second resistor between the bridge output and bridge ground. The first diagnostic switch closes during a first diagnostic waveform phase and opens during all other phases of operation. The second diagnostic switch closes during a second and third waveform phase and opens during all other phases of operation. The diagnostic waveforms are used to test major signal conditioning and fault reporting paths of the ASIC.

Abstract: Detection of excessive negative offset of a condition responsive sensor such as a pressure responsive full Wheatstone bridge element (10) and circuitry associated therewith is obtained by taking the sensor's output signal, preferably after the signal has been compensated for both gain and offset and comparing (Q1) the signal (Vx) with a reference voltage (VREF1) selected to reflect an unobtainable stimulus input condition and driving the compensated signal to a fault level when the compensated signal exceeds the reference voltage.

Abstract: A port fitting (12, 42) is formed with a closed, pedestal end forming a diaphragm (12a, 42b) on which a strain gauge sensor (22) is mounted. A support member (16, 44) is received on the pedestal end and is formed with a flat end wall (16a, 44a) having an aperture (16c, 44c) aligned with the sensor. A portion of a flexible circuit assembly (24a, 58a) is bonded to the flat end wall. An electronics chamber is formed in a connector (18, 46) which is inverted and maintained at a selected height adjacent to the flat end wall of the support member to facilitate soldering of the flexible circuit to terminals (20, 48) in the connector and electronic components to the flexible circuit. The port fitting, when assembled to the support member, is also maintained at the selected height adjacent to the inverted connector to facilitate wire bonding the sensor to the bonded portion of the flexible circuit.

Abstract: An in-range fault detection system for a full wheatstone bridge element (12) having piezoresistive elements (R1, R2, R3, R4) has bridge outputs (INP, INM) connected to measuring means in the form of a first circuit portion (13) to provide a common mode voltage (VCM). A second circuit portion (14) is used to provide a centering voltage (C*VBRG) equal to the common mode voltage at the time of sensor calibration and a third circuit portion (15) is used to provide a small window voltage (W*VBRG) which is a fraction of bridge voltage. The value (W*VBRG) is subtracted from (C*VBRG) at a first summing circuit (SUM1) and added to (C*VBRG) at a second summing circuit (SUM2) and the results are each compared to the common mode voltage by comparators (Q1, Q2) which are then determined to be within or without a window of valid values by an OR gate (Q3).

Abstract: An application specific integrated circuit or ASIC (MSC) is connected to a plurality of bridge type sense elements (1-6) for analog multiplexing (10a, 10b, 10c) the outputs from a selected sense element to a common signal conditioning path (10f). The bridge type sense elements are biased through an electronically programmable resistor (10d1) to derive a temperature signal. The signal conditioning path provides electronically programmable correction for offset and gain proportional to the sensed condition, e.g., fluid pressure. Complete sensor characterization data provided at the time of manufacture is stored in non-volatile memory (10h) which is downloaded to a host controller (12) on command. The ASIC also includes diagnostic test bridges (BR1, BR2) for diagnosing ASIC faults and a signal diagnostic path (10m) for diagnosing sense element and sense element connection faults.

Abstract: Detection of excessive negative offset of a condition responsive sensor such as a pressure responsive full Wheatstone bridge element (10) and circuitry associated therewith is obtained by taking the sensor's output signal, preferably after the signal has been compensated for both gain and offset and comparing (Q1) the signal (Vx) with a reference voltage (VREF1) selected to reflect an unobtainable stimulus input condition and driving the compensated signal to a fault level when the compensated signal exceeds the reference voltage.

Abstract: A full Wheatstone bridge sensor has conditioning electronics of an ASIC connected thereto. Two independently controlled diagnostic switches (S1, S2) in the ASIC are commonly connected to one of the bridge output nodes. The first diagnostic switch connects first resistor between the bridge output node and bridge supply voltage and the second diagnostic switch connects a second resistor between the bridge output and bridge ground. The first diagnostic switch closes during a first diagnostic waveform phase and opens during all other phases of operation. The second diagnostic switch closes during a second and third waveform phase and opens during all other phases of operation. The diagnostic waveforms are used to test major signal conditioning and fault reporting paths of the ASIC.

Abstract: A solid state power controller for switching power on and off to an electrical load which also serves as a circuit protection device protecting the load and/or the wire connected between the load output terminal of the controller and ground from thermal damage due to current overload is shown. Upon current overload the controller interrupts current to the load in a time inversely proportional to the square of the magnitude of the overload. The controller also limits the load current to a selected maximum level by controlling the drain-source resistance of power MOSFETs (PS1-7) used for switching power. A secondary interrupt is provided in the event that the junction temperature of the MOSFETs has risen to a selected maximum level. A thermal memory feature is included for both interrupt signals. The controller is controlled by a single on/off input line (COMMAND) and provides both a status (STATUS) and trip (TRIP) output line. The status can be configured to monitor load voltage or load current flow.

Abstract: A variable differential transformer system (10), both linear and rotary (L/RVDT) includes a primary coil (12) drive by a primary drive (20) having a triangle wave generator whose frequency is set by an external frequency control (R.sub.osc and C.sub.osc) which includes compensation for gain temperature error. Secondary coils (14, 16) have a common connection for balanced loading with an input stage arrangement (R7, R8, R9, R10) providing low common mode range and a way to differentiate between normal operation and coil faults detected by a fault detection network (28). Synchronous demodulation (22) extracts both magnitude and direction from the secondary coil signals. Electronic calibration (24) is shown which compensates for sensor offset and gain. Sensor offset calibration is accomplished by adding a percentage of the synchronous demodulation reference wave form to the differential secondary signal.

Abstract: A variable differential transformer system (10), both linear and rotary (L/RVDT) includes a primary coil (12) drive by a primary drive (20) having a triangle wave generator whose frequency is set by an external frequency control (R.sub.osc and C.sub.osc) which provides compensation for gain temperature error. Secondary coils (14, 16) have a common connection for balanced loading with an input stage arrangement (R7, R8, R9, R10) providing low common mode range and a way to differentiate between normal operation and coil faults detected by a fault detection network (28). Synchronous demodulation (22) extracts both magnitude and direction from the secondary coil signals. Electronic calibration (24) compensates for sensor offset and adjust circuit gain by adding a percentage of the synchronous demodulation reference waveform to the secondary differential voltage.

Abstract: A solid state power controller for switching power on and off to an electrical load which also serves as a circuit protection device protecting the load and/or the wire connected between the load output terminal of the controller and ground from thermal damage due to current overload is shown. When a current overload exists the controller interrupts current to the load in a time inversely proportional to the square of the magnitude of the overload as shown in a trip time vs load current curve. The controller also limits the load current to a selected maximum level by controlling the drain-source resistance of power MOSFETs used for switching the power. A secondary interrupt is provided in the event that the junction temperature of the MOSFETs has risen a selected maximum level. A thermal memory feature is included for both interrupt signals. The controller is controlled by a single on/off input line and provides both a status and trip output line to indicate its state.

Abstract: A high voltage, high current DC switch is shown having a single pole, double throw relay and a solid state power switch such as an IGBT or MOSFET transistor. Voltage is switched by means of the solid state switch while steady state current is conducted through the relay load contact. Several different protector devices are used in the event of circuit malfunction including a combination of thermal and current fuses and resettable thermostats.