摘要:
A sensor having freeze resistant features is disclosed. The sensor includes a sensor die and a buffer member that are assembled for attachment to a process fluid conduit. The buffer member defines an opening in fluid communication with the process fluid. The sensor die has a flexible diaphragm, and a capillary channel establishes fluid communication between the diaphragm area of the sensor die and the opening in the buffer member.
摘要:
A flow sensor apparatus that utilizes a pressure sensor with media isolated electrical connections. A cap can be attached to topside of the pressure sensor over a diaphragm to protect bond pads and wire bonds from a fluid media. A flow channel can be etched on the cap with an opening and exit on the sides of the cap so that liquid can flow through the flow channel. An inlet port and an outlet port can be attached to the channel's opening and exit to allow for fluid flow over the diaphragm. The flow channel creates a larger pressure over portions of the diaphragm that increases the deflection of the diaphragm, which increases an output signal of the pressure sensor. V-grooves can be created on two sides of the pressure sensor and in the cap to create the channel for the fluid in and out of the cap's cavity.
摘要:
A robust sensor, such as a robust flow sensor or pressure sensor, is provided. In one illustrative embodiment, a robust flow sensor includes one or more flow sensor components secured relative to a membrane, and a substrate for supporting the membrane. In some cases, the one or more flow sensor components may be substantially thermally isolated from the substrate by the membrane. One or more wire bond pads may be situated adjacent to a first side of the substrate and may be provided for communicating signals relative to the one or more flow sensor components. A top cap may be situated adjacent to the first side of the substrate and secured relative to the substrate. The top cap may define at least part of a fluid inlet and/or an outlet of the flow sensor assembly, and may at least partially define a flow channel that extends from the inlet, past at least one of the one or more flow sensor components, and out the outlet of the flow sensor assembly. The top cap may be structured and attached relative to the first side of the substrate such that the one or more wire bond pads are not exposed to a fluid in the flow channel, but are accessible for electrical connection to an external device. While a flow sensor is used as an example, it is contemplated that any suitable sensor may be used, as desired.
摘要:
A flow sensor apparatus that utilizes a pressure sensor with media isolated electrical connections. A cap can be attached to topside of the pressure sensor over a diaphragm to protect bond pads and wire bonds from a fluid media. A flow channel can be etched on the cap with an opening and exit on the sides of the cap so that liquid can flow through the flow channel. An inlet port and an outlet port can be attached to the channel's opening and exit to allow for fluid flow over the diaphragm. The flow channel creates a larger pressure over portions of the diaphragm that increases the deflection of the diaphragm, which increases an output signal of the pressure sensor. V-grooves can be created on two sides of the pressure sensor and in the cap to create the channel for the fluid in and out of the cap's cavity.
摘要:
A differential pressure sensor includes two pressure ports for allowing media to pass into contact with both the top and bottom sides of the diaphragm. A silicon pressure sensor die can be attached between the pressure ports using die attach materials for sensing a differential pressure between the media to evaluate media differential pressure. A cap with an opening can be placed on topside of a diaphragm formed in the silicon pressure die. The silicon pressure die can include die bond pads that can be electrically connected to the diaphragm to output electrical signals. The cap can seal the die bond pads from the harsh media and route the electrical signals therein. Media can pass through the opening in the cap such that a media path to the top of the diaphragm is not exposed to the die bond pads of the silicon pressure die to ensure long-term sensor reliability.
摘要:
A differential pressure sensor includes two pressure ports for allowing media to pass into contact with both the top and bottom sides of the diaphragm. A silicon pressure sensor die can be attached between the pressure ports using die attach materials for sensing a differential pressure between the media to evaluate media differential pressure. A cap with an opening can be placed on topside of a diaphragm formed in the silicon pressure die. The silicon pressure die can include die bond pads that can be electrically connected to the diaphragm to output electrical signals. The cap can seal the die bond pads from the harsh media and route the electrical signals therein. Media can pass through the opening in the cap such that a media path to the top of the diaphragm is not exposed to the die bond pads of the silicon pressure die to ensure long-term sensor reliability.
摘要:
A flow sensor apparatus that utilizes a pressure sensor with media isolated electrical connections. A cap can be attached to topside of the pressure sensor over a diaphragm to protect bond pads and wire bonds from a fluid media. A flow channel can be etched on the cap with an opening and exit on the sides of the cap so that liquid can flow through the flow channel. An inlet port and an outlet port can be attached to the channel's opening and exit to allow for fluid flow over the diaphragm. The flow channel creates a larger pressure over portions of the diaphragm that increases the deflection of the diaphragm, which increases an output signal of the pressure sensor. V-grooves can be created on two sides of the pressure sensor and in the cap to create the channel for the fluid in and out of the cap's cavity.
摘要:
A flow sensor apparatus that utilizes a pressure sensor with media isolated electrical connections. A cap can be attached to topside of the pressure sensor over a diaphragm to protect bond pads and wire bonds from a fluid media. A flow channel can be etched on the cap with an opening and exit on the sides of the cap so that liquid can flow through the flow channel. An inlet port and an outlet port can be attached to the channel's opening and exit to allow for fluid flow over the diaphragm. The flow channel creates a larger pressure over portions of the diaphragm that increases the deflection of the diaphragm, which increases an output signal of the pressure sensor. V-grooves can be created on two sides of the pressure sensor and in the cap to create the channel for the fluid in and out of the cap's cavity.
摘要:
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.
摘要:
A method and system for adjusting characteristics of a relative humidity sensor in order to achieve a desired value of accuracy is presented. A relative humidity sensor charge balance circuit includes a series of sensing capacitors Cx1, Cx2 including a thin porous platinum top plate, a humidity sensitive polyimide dielectric, and two metal bottom plates on a semiconductor substrate; and two fixed oxide capacitances Cref, and C0. Changes in humidity affect the humidity sensitive dielectric thereby causing changes in the sensing capacitive value of the capacitive circuit. The charge in the sensing capacitor and the fixed capacitor C0 can be controlled separately by adjusting and/or trimming the supply voltage using a voltage trimmer; thereby the slope and offset of the relative humidity sensor circuit can be modified and controlled to particular desired values.