Patent application number | Description | Published |
20080222884 | Packaging for chip-on-board pressure sensor - A method of packaging for chip-on-board pressure sensor that includes a buffer layer with a coefficient of thermal expansion (CTE) intermediate between the transducer and a main chip-on-board substrate by which thermally induced package stresses can be greatly reduced or eliminated. Additionally, the use of a buffer layer with higher stiffness (elastic modulus) than the chip-on-board substrate further prevents or reduces flexural (bending) stresses from being transferred to the transducer. Such a buffer layer also enables a wider choice of materials for bonding and stable performance of pressure sensor in harsh media and environmental conditions. The pressure transducer can be adhesively bonded to a ceramic layer, which in turn can be adhesively bonded to an epoxy laminate chip-on-board substrate. | 09-18-2008 |
20090056410 | Self diagnostic measurement method to detect microbridge null drift and performance - A self-diagnostic measurement method to detect microbridge null drift and performance. An ASIC can be designed to include a self-diagnostic feature that automatically occurs at start up or upon command in Normal Operation whereby the temperature compensated microbridge null can be measured in a state of very low thermal energy and allows for the tracking of microbridge null stability versus time. An Airflow Combi-Sensor ASIC (Heimdal) with its strategic partner ZMD can be developed and can be implemented in the form of a self-diagnostic feature that occurs when power is first applied to the ASIC or upon command. When the self-diagnostic is initiated, power is removed and after the electronics have settled, a small power can be applied to the microbridge to measure the bridge null with reduced sensitivity to flow due to self-heating. | 03-05-2009 |
20090145243 | ROBUST MEMS FLOW DIE WITH INTEGRATED PROTECTIVE FLOW CHANNEL - A MEMS flow sensor has a flow channel that avoids wire bond pads and ancillary circuit elements. A fluid can move from the bottom of the sensor substrate, though an inlet hole, over a sensing element on the top of the substrate, and then through an outlet hole. The inlet hole and the outlet hole can pass from the substrate top to the substrate bottom. A top cap can be fixed to the top of the substrate such that it covers the sensing element, the inlet hole, and the outlet hole. The top cap constrains the flow channel and keeps fluid, either gaseous or liquid, from exiting the channel and contacting the wire bond pads or ancillary circuit elements. | 06-11-2009 |
20090151464 | DIFFERENTIAL PRESSURE SENSE DIE BASED ON SILICON PIEZORESISTIVE TECHNOLOGY - A method and apparatus for designing a differential pressure sense die based on a unique silicon piezoresistive technology for sensing low differential pressure in harsh duty applications is disclosed. The pressure sense die comprises of an etched pressure diaphragm and a hole that is drilled through the sense die wherein the pressure sense die possess a backside and a front side and are associated with varying pressures. A top cap can be attached to the front side and an optional constraint for stress relief can be attached to the backside of the differential pressure sense die. The top cap and the constraint comprise of glass and/or silicon and can be attached with an anodic bonding process or glass frit process. | 06-18-2009 |
20100122583 | DESIGN OF WET/WET DIFFERENTIAL PRESSURE SENSOR BASED ON MICROELECTRONIC PACKAGING PROCESS - Method and system for a wet/wet differential pressure sensor based on microelectronic packaging process. A top cap with a hole can be attached to a topside of a MEMS-configured pressure sense die with a pressure sensing diaphragm in order to allow sensed media to come in contact with the topside of the pressure sensing diaphragm. An optional constraint with a hole for stress relief can be attached to a backside of the pressure sense die. Adhesive and/or elastomeric seals and/or solder can be utilized to seal the pressure sense die allowing sensed media to come in contact with both sides of the pressure sensing diaphragm without coming into contact with wirebonds and other metallized surfaces. The MEMS-configured pressure sense die can also be bonded to a substrate with standard die attach materials. Such microelectronic packaging processes yield a high performance and cost effective solution thereby providing wet-wet pressure sensing capability. | 05-20-2010 |
20110132096 | PRESSURE SENSOR WITH ON-BOARD COMPENSATION - The present disclosure relates generally to pressure sensors, and more particularly, to methods and apparatus for compensating pressure sensors for stress, temperature and/or other induced offsets and/or errors. In one illustrative embodiment, a pressure sensor may include a pressure sensing die mounted to a substrate of a pressure sensor package. The pressure sensor die may include on-board compensation. In some instances, the on-board compensation may include an on-board heating element and an on-board zener diode trim network, both situated on or in the pressure sensing die. The zener diode trim network may include one or more zener diodes and one or more resistive elements, where the zener diodes can be selectively activated to “trim” the resistive network to compensate for one or more offsets and/or errors of the pressure sensor. The on-board heating element may be configured to heat the pressure sensor assembly to various temperatures so that temperature related offsets and/or errors may be identified, and then compensated for with the zener diode trim network. | 06-09-2011 |
Patent application number | Description | Published |
20100154532 | THERMAL ANEMOMETER FLOW SENSOR APPARATUS WITH A SEAL WITH CONDUCTIVE INTERCONNECT - A flow sensor apparatus and method. A seal with a conductive interconnect is provided that includes a mass flow sense element mounted to a housing containing a thick film and/or thin film bridge structure for sensing media (e.g., mass flow) within a flow tube. The seal effectively isolates wirebond pads and electrical connections from the sensed media. The media, whether liquid or gas, can contain ionics that eventually contaminate the top of the mass flow sense element. The use of the seal with the conductive interconnect thus seals off the electrical connections and prevents exposure to the sensed media. | 06-24-2010 |
20100206046 | FLOW-THROUGH PRESSURE SENSOR APPARATUS - A flow-through pressure sensor apparatus that reduces the dead space of a flow tube utilized to provide fluid communication between a pressure sense die and a fluid and with an absolute minimum trapped volume. A cover (e.g., plastic) with two-molded ports can be added to one side of the pressure sense die utilizing molded-in solder pins to improve ruggedness and rigidity. A temperature and a humidity sensor can also be mounted to a substrate (e.g., ceramic) in the flow path and can be connected to a programmable compensation integrated circuit on the opposite side utilizing a clip end of mounting pins or by vias through the substrate outside a pressurized area. | 08-19-2010 |
20100305465 | MULTI-DYNAMIC-RANGE SENSOR - A sensing system that produces a multi-dynamic range output is provided. In an illustrative embodiment, a first channel and a second channel receive an analog output signal from a sensing element. The first channel provides a first digital output signal that has a first dynamic range, and the second channel provides a second digital output signal that has a second narrower dynamic range. In some cases, the second narrower dynamic range falls within the first dynamic range, and the first digital output signal may provide a first resolution and the second digital output signal may provide a second greater resolution. The dynamic range and/or resolution of one or more of the first channel and second channel may be dynamically reconfigurable, if desired. | 12-02-2010 |
20120144921 | INCREASED SENSOR DIE ADHESION - Methods and devices for adhesively bonding a sensor die to a substrate are described. In some cases, a sensor assembly may include a pressure sensor die mounted to a substrate with an adhesive. The pressure sensor die may be fabricated to include a back-side having one or more adhesion features (e.g. recesses or indentations), which increase the surface area of the pressure sensor die that is in contact with the adhesive, to thereby increase the adhesion force therebetween. In some cases, the one or more adhesion features may define a non-planar interface between the pressure sensor die and the adhesive which, in some instances, may reduce the formation and/or propagation of cracks in the adhesive, which also may help increase the adhesion force therebetween. | 06-14-2012 |
20120192642 | FLOW SENSOR ASSEMBLY WITH INTEGRAL BYPASS CHANNEL - Flow sensor assemblies having increased flow range capabilities are disclosed. In one illustrative embodiment, a flow sensor assembly includes a housing with an inlet flow port, an outlet flow port, a fluid channel extending between the inlet flow port and the outlet flow port, and a bypass channel having a pair of taps fluidly connected to the fluid channel at separate locations. A flow sensor for sensing a measure related to a flow rate of a fluid flowing through the fluid channel can positioned in the bypass channel. A pressure differential between the two taps of the bypass channel can drive a fraction of a fluid flowing through the fluid channel through the bypass channel. The flow sensor assembly may be configured to achieve, control, and/or balance a desired fraction of fluid flow through the bypass channel and past the flow sensor. | 08-02-2012 |
20120192643 | FLOW SENSOR WITH ENHANCED FLOW RANGE CAPABILITY - Flow sensor assemblies having increased flow range capabilities are disclosed. In one illustrative embodiment, a flow sensor assembly includes a housing with an inlet flow port, an outlet flow port, and a fluid channel extending between the inlet flow port and the outlet flow port. One or more partitions are provided in the fluid channel of the housing to define two or more fluid sub-passages. A flow sensor, for sensing a measure related to a flow rate of a fluid flowing through the fluid channel, is positioned in one of the two or more fluid sub-passages. In some cases, the cross-sectional area of each of the two or more fluid sub-passages may be substantially the same, but this is not required. The housing may be formed from a single molded part defining the inlet and outlet flow ports, at least a portion of the fluid channel, and one or more of the partitions. In this case, a top cover may be provided and mounted to the housing to define the remaining portion of the fluid channel, if desired. | 08-02-2012 |
20120286872 | METHOD AND APPARATUS FOR INCREASING THE EFFECTIVE RESOLUTION OF A SENSOR - Methods and devices for increasing a sensor resolution are disclosed. In one example, a two measurement process is used. A first measurement is used to effectively measure across a full range (e.g. 0 to 5 VDC) of the sensor. This first measurement may identify the current operating point of the sensor (e.g. 3.5 VDC). A second measurement may then be made to effectively measure across a sub-range of the sensor that encompasses the current operating point of the sensor (e.g. across a sub-range of 3.0 to 4.0 VDC for a current operating point of 3.5 VDC). The gain of the amplifier may be raised during the second measurement to produce a higher resolution measurement. In some cases, the first measurement may be used to determine an appropriate offset that may be applied so as to scale the amplifier to the desired sub-range of sensor that includes the current operating point of the sensor. In some cases, the two measurements may be used together to compute an effectively higher resolution measurement signal. In some cases, this may allow for a smaller and/or cheaper sensor to be used, while still achieving good results. | 11-15-2012 |
20130055821 | PACKAGED SENSOR WITH MULTIPLE SENSORS ELEMENTS - The present disclose relates to sensor including multiple sensor elements. In some cases, the multiple sensor elements may be mounted on a single substrate and each may be configured to sense a single parameter with different resolutions, sensitivities, and/or ranges, and/or the multiple parameters. In one example, multiple pressure sensing die may be mounted in a single package, and each may be configured as a differential pressure sensor, an absolute pressure sensor, and/or a gauge pressure sensor, as desired. | 03-07-2013 |
20130055826 | MEMS AIRFLOW SENSOR DIE INCORPORATING ADDITIONAL CIRCUITRY ON THE DIE - A MEMS airflow sensor die having a heater control circuit, differential instrumentation amplifier, temperature compensation, and/or offset correction circuitry integrated with an airflow sensor on the MEMS die. The added circuitry may be placed on space available on the basic airflow die with MEMS fabrication techniques without enlarging the sensor die. The die with the added circuitry may result in a device having a reduced form factor, improved reliability and lower cost. | 03-07-2013 |
20130213131 | FLOW SENSOR ASSEMBLY WITH INTEGRAL BYPASS CHANNEL - Flow sensor assemblies having increased flow range capabilities are disclosed. In one illustrative embodiment, a flow sensor assembly includes a housing with an inlet flow port, an outlet flow port, a fluid channel extending between the inlet flow port and the outlet flow port, and a bypass channel having a pair of taps fluidly connected to the fluid channel at separate locations. A flow sensor for sensing a measure related to a flow rate of a fluid flowing through the fluid channel can positioned in the bypass channel. A pressure differential between the two taps of the bypass channel can drive a fraction of a fluid flowing through the fluid channel through the bypass channel. The flow sensor assembly may be configured to achieve, control, and/or balance a desired fraction of fluid flow through the bypass channel and past the flow sensor. | 08-22-2013 |
20130271050 | MULTI-PHASE BRUSHLESS DC MOTOR CONTROL INTEGRATED CIRCUIT HAVING MAGNETIC SENSOR AND BAND-GAP TEMPERATURE SENSOR FORMED THEREON - An integrated circuit for implementing brushless DC motor control includes a substrate, a band gap temperature sensor, and a magnetic sensor. The substrate has a temperature output pin for connection to an external device and a magnetic sensor output pin for connection to the external device. The band gap temperature sensor is formed on the substrate and is configured to sense temperature and supply a temperature signal representative of the sensed temperature to the temperature output pin. The magnetic sensor is formed on the substrate and is configured to sense magnetic field variations and supply a sensor output signal representative thereof to the magnetic sensor output pin. | 10-17-2013 |
20130298688 | TEMPERATURE COMPENSATED FORCE SENSOR - A force sensor may include a housing having a cavity enclosing a sense die, an actuating element and an elastomeric seal. The sense die may have a force sensing element for sensing a force applied to a surface of the sense die, and a temperature compensation circuit. The temperature compensation circuit may be located on the surface of the sense die and may be configured to at least partially compensate for the temperature sensitivity of the force sensing element. The actuating element may extend outside the housing and be used to transfer a force applied externally from the housing to the sense die. The elastomeric seal may include one or more conductive elements separated from the edge of the elastomeric seal by an insulating elastomeric material. | 11-14-2013 |
20150020587 | Temperature Compensation Module For a Fluid Flow Transducer - Apparatus and associated methods relate to a temperature-compensated drive for a heating element used in a micro-bridge flow sensor. In some embodiments, the heating element may be located substantially between two temperature sensors. The two temperature sensors may be convectively coupled to the heater by a fluid ambient. When the fluid ambient is flowing, one of the temperature sensors may be upstream of the heating element, and one of the temperature sensors may be downstream. The fluid may be heated by the heating unit, and this heated fluid may then flow past the downstream temperature sensor. The two temperature sensors may be used in a Wheatstone bridge configuration. In some embodiments, an output signal of the Wheatstone bridge may be indicative of a measure of fluid flow. The temperature-compensated drive for the heating element may enhance, for example, the flow meter's disturbance rejection of ambient temperature. | 01-22-2015 |