508 results about "Positive temperature" patented technology

The invention relates to the technical field of integrated circuits, in particular to a band-gap reference voltage source, which comprises a high-order compensation circuit, a low-order compensation circuit, a low-order compensation circuit, a low-order compensation circuit and a low-order reference circuit, the band-gap reference circuit is used for generating a positive temperature coefficient voltage and a negative temperature coefficient voltage, performing first-order temperature compensation on the negative temperature coefficient voltage by using the positive temperature coefficient voltage, performing high-order curvature compensation on the negative temperature coefficient voltage based on the target compensation current, determining the compensated voltage as a reference voltage and outputting the reference voltage; according to the band-gap reference voltage source, high-order compensation is introduced through the sub-threshold MOS tube, the negative temperature coefficient voltage can be well reduced, the reference voltage with the temperature coefficient approximate to zero is obtained, and practicability is high.

The present invention belongs to the technical field of microwave dielectric ceramics, and discloses a reducing-resistant microwave dielectric ceramic temperature-frequency characteristic regulator. Among them, the application of a microwave dielectric ceramic material as a microwave dielectric ceramic temperature-frequency characteristic regulator, and the chemical formula of the microwave dielectric ceramic material satisfies (AO)3(BO)(XO2)2, where A = Ba x Sr y , B = Mn h Mg k , X = Si m Ti n ; x + y = 1, h + k = 1, m + n = 1, 0 ≤ x ≤ 1, 0.6 ≤ h ≤ 1, 0.8 ≤ m ≤ 1; and when h = 1 and m = 1, x ≠ 0; this microwave dielectric ceramic material can be adjusted by addition to regulate the overall temperature coefficient of resonance frequency of the ceramic system. By improving the composition of the material, the obtained microwave dielectric ceramic material has the characteristics of adjustable dielectric constant, low dielectric loss, and high positive temperature coefficient of resonance frequency, and can especially be used as a microwave dielectric ceramic temperature-frequency characteristic regulator with a strong regulation effect.

A bandgap reference circuit includes a first, a second and a third current source, a first and a second amplifier. The first, the second and the third current source each includes two cascode PMOS transistors for reducing the voltage stress applied to PMOS transistors when receives a high power supply voltage. The first amplifier controls the PMOS transistors in the first and the second current source to ensure that the PMOS transistors have enough headroom when receives a low power supply voltage. The second amplifier provides a gain-boosting loop to prevent the system mismatch of the PMOS transistors in the first, the second and the third current source. A temperature coefficient adjustment unit introduces positive temperature coefficients and negative temperature coefficients in the currents generated by the first and second current source, and a resistor generates the reference voltage according to a current duplicated by the third current source.

The invention discloses a low-temperature drift reference circuit, which belongs to the technical field of electronic circuits and comprises a starting unit, a reference core unit and a base current absorption unit, the starting unit is connected with the reference core unit and the base current absorption unit, and the reference core unit is connected with the base current absorption unit. According to the low-temperature-drift reference circuit, the T-type resistor network is adopted, negative temperature coefficient voltage is compensated depending on a positive temperature coefficient voltage expansion item, and low-temperature-drift reference voltage can be obtained; the magnitude of the reference voltage can be adjusted by changing the proportional relation between the resistance type and the resistance value of the resistance network and the current mirror.

The invention relates to the technical field of power monitoring, in particular to a power online monitoring method, system and device for a PTC heater. According to the method, the environmental instability of the electrical parameters is determined according to the unstable condition of the current current and the historical current at the temperature approaching the Curie point; the heat dissipation condition change degree is obtained through the trend fluctuation of the temperature deviation in the time sequence; determining a temperature deviation time period through the deviation with the gear temperature, and evaluating the environmental heat dissipation disorder degree according to the difference condition between the temperature deviation time periods; the monitoring sensitivity is obtained through the electrical parameter environment stability, the heat dissipation condition change degree and the environment heat dissipation disorder degree, and the power monitoring range is adjusted for monitoring. By analyzing the influence of the heat dissipation environment on the PTC heater, the power quantification range is adjusted at different monitoring degrees, the monitoring accuracy in different environments is improved, and the monitoring result is more reliable.

An accelerometer includes a housing, a proof mass assembly encased in the housing, and one or more heating elements configured to heat the proof mass assembly in response to an electrical current. The one or more heating elements include a positive temperature coefficient of resistance (PTC) material. The PTC material exhibits a relatively high increase in resistance above a threshold temperature. For example, a ratio of the resistance of the PTC material above the threshold temperature to the resistance of the PTC material at room temperature (PTC ratio) is greater than five.

The invention discloses a low-temperature-drift band-gap reference source circuit. The low-temperature-drift band-gap reference source circuit comprises a starting circuit, a PTAT current generating circuit, a CTAT current generating circuit and an output circuit. The PTAT current generation circuit is used for generating positive temperature coefficient current, and adopts a power supply voltage isolation structure consisting of two PMOS (P-channel Metal Oxide Semiconductor) tubes and two NMOS (N-channel Metal Oxide Semiconductor) tubes to isolate the interference of power supply voltage; the CTAT current generating circuit is used for generating a negative temperature coefficient current and adopts a clamping structure consisting of two triodes, so that the CTAT current generating circuit is not influenced by a power supply voltage; and the output circuit is used for outputting low-temperature-drift reference current and / or voltage. An operational amplifier clamping structure is not used, the complex structure of an integrated operational amplifier is omitted, the circuit structure is simplified, the area and power consumption are reduced, the influence of offset voltage of the integrated operational amplifier can be avoided, and practicability is high. In addition, the reference circuit further comprises a temperature compensation circuit, temperature high-order compensation is carried out through a feedback network formed by two resistors, and the reference current and the reference voltage are more accurate.

The invention discloses a high-voltage fast recovery diode with a positive temperature characteristic and a manufacturing method of the high-voltage fast recovery diode. A central region of the device is a P-type doped active region which is used as an anode when the device works in the forward direction; p-type doped field limiting rings are arranged on the two sides of the active region and serve as voltage dividing rings of the device, and the field limiting rings and the active region are doped independently; an N-type doped cut-off ring is arranged on the outermost periphery of the device and provides an electric field cut-off effect; a metal field plate is arranged above each field limiting ring to improve the distribution of a peripheral electric field and improve the stability of the device; except for the position of the contact hole, CVD, silicon nitride and polyimide in the vertical direction of the device are used as passivation layers of the device to isolate the influence of external moisture, charges and the like, so that the reliability of the device is improved; metal is directly deposited above the active region to serve as an anode of the device; and a layer of metal is evaporated on the back of the device after being thinned to serve as a device cathode. A platinum diffusion and electron irradiation process is used as a minority carrier lifetime control technology to adjust the temperature characteristic of the device.

The utility model discloses a PTC heating device, an air supply device and air treatment equipment, and belongs to the technical field of electric appliances, in the PTC heating device, a plurality of heating units are arranged in a zigzag mode along a fold line track, so that the PTC heating device can be matched with an arc-shaped or curve-shaped air outlet duct, and the PTC heating device can be applied to the air supply device with the curve-shaped air outlet duct. Because each heating unit is arranged on one line segment of the fold line, the heating piece and the heat dissipation piece of each heating unit can roughly extend in the same direction, the curvature difference between the heating piece and the heat dissipation piece is reduced, the problem that a gap is generated between the heating piece and the heat dissipation piece is solved, the attaching degree of the heating piece and the heat dissipation piece is improved, and the service life of the heating piece and the heat dissipation piece is prolonged. The contact area of the heating piece and the heat dissipation piece is increased, and the heating uniformity is improved. Moreover, the plurality of heating units are mutually connected through the connecting assemblies, on one hand, the structural integrity of the heating device is guaranteed, and on the other hand, the overall heating uniformity of the heating device can be improved.

A mouthpiece for a vaporizer device includes a vapor inlet and an aerosol outlet. A first plurality of air inlets and a second plurality of air inlets are disposed between the vapor inlet and the aerosol outlet and configured to provide air streams. The air streams form a first vortex and a second vortex. The air streams mix with a vapor entering from the vapor inlet and form an aerosol exiting through the aerosol outlet. Related apparatus, systems, techniques and articles are also described.

The invention discloses a temperature sensor, a temperature acquisition device and electronic equipment, in the temperature sensor, a temperature sensing current generation module responds to target temperature change, and provides a first current signal with a positive temperature coefficient for a current conversion module; the current conversion module converts the first current signal into a first voltage signal with a negative temperature coefficient and generates and outputs a second voltage signal to the voltage regulation module according to the first voltage signal, and the voltage value of the second voltage signal is an integral multiple of the voltage value of the first voltage signal; the voltage regulation module receives the second voltage signal and outputs a third voltage signal to the analog-to-digital converter, and the voltage value of the third voltage signal is smaller than that of the second voltage signal; the analog-to-digital converter receives the third voltage signal and outputs a target digital signal, and the target digital signal is used for representing the temperature measured by the temperature sensing front-end circuit. According to the arrangement, the accuracy of temperature detection can be improved, and the temperature sensor is high in accuracy, small in size and low in power consumption.

The utility model discloses a water and electricity separated PTC heater, which comprises a PTC heating core body, a liquid box and a heating base, a cavity is arranged in the liquid box, one end of the liquid box is provided with an opening communicated with the cavity, at least one first partition plate is arranged in the cavity so as to divide the cavity into at least two mutually independent liquid cavities, and the heating base is arranged in the cavity. PTC (Positive Temperature Coefficient) shells with the same number as the liquid cavities are arranged on the heating base, the PTC heating core bodies are respectively arranged in the PTC shells, the PTC shells are respectively arranged in the liquid cavities, a first sealing ring is arranged on the heating base, the heating base is arranged in the opening and is sealed through the first sealing ring, a liquid inlet is formed in the bottom of one liquid cavity, and a liquid outlet is formed in the bottom of the other liquid cavity. A liquid outlet is formed in the bottom of the other liquid cavity, and a notch allowing liquid to flow through is formed in the first partition plate. Compared with the prior art, water and electricity separation is achieved.

An over-current protection device includes a first metal layer, a second metal layer and a heat-sensitive layer laminated therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a first polymer and a conductive filler. The first polymer consists of polyvinylidene difluoride (PVDF), and PVDF exists in different phases such as α-PVDF, β-PVDF and γ-PVDF. The total amount of α-PVDF, β-PVDF and γ-PVDF is calculated as 100%, and the amount of γ-PVDF accounts for 33% to 42%.

An acoustic wave filter includes a substrate and a piezoelectric layer over the substrate. First acoustic wave resonators are disposed over the piezoelectric layer and arranged in series along a first branch, and second acoustic wave resonators are disposed over the piezoelectric layer, arranged in parallel, and connected to the first branch and to ground. The first and second acoustic wave resonators include an interdigital transducer electrode interposed between a pair of reflectors. A layer of positive temperature coefficient of frequency dielectric material is disposed over one or more of the first plurality of acoustic wave resonators to control the temperature coefficient of frequency and improve temperature stability of the acoustic wave filter.

The invention aims to provide the system and the method for precisely measuring the heat conduction performance of the vapor chamber, which can eliminate errors caused by contact thermal resistance by utilizing the vapor chamber, and is high in spatial resolution and non-destructive in test. The uniform temperature plate heat conduction performance precision measurement system comprises a temperature measurement module, the temperature measurement module comprises a heating module and a plurality of measurement modules, each measurement module comprises a thermocouple probe and a force adjusting mechanism which are connected, and each thermocouple probe comprises a T-shaped thermocouple, a positive electrode temperature measurement pressure head and a negative electrode temperature measurement pressure head. The positive temperature measuring pressure head and the negative temperature measuring pressure head are mutually independent and are arranged in a floating mode relative to the force adjusting mechanism, the positive temperature measuring pressure head is provided with a copper thermocouple wire connected to the positive electrode of the T-type thermocouple, and the negative temperature measuring pressure head is provided with a constantan thermocouple wire connected to the negative electrode of the T-type thermocouple. The copper thermocouple wire and the constantan thermocouple wire are short-circuited and form a thermocouple loop when being in contact with the vapor chamber at the same time; the method is realized based on the measurement system. The method is applied to the technical field of vapor chamber testing.

The invention relates to the technical field of analog integrated circuits, in particular to an index curvature compensation band-gap reference source circuit and system. Comprising a band-gap core sub-circuit, an index curvature compensation sub-circuit, a power interface and a voltage interface, wherein the band-gap core sub-circuit is used for generating positive temperature coefficient current; and the index curvature compensation sub-circuit is used for receiving the positive temperature coefficient current so as to generate a base current and further output an index curvature compensation voltage to the voltage interface. According to the band-gap reference source circuit with the exponential curvature compensation, the positive temperature coefficient current of the band-gap core sub-circuit is converted into the base current through the exponential curvature compensation sub-circuit, so that the influence of a first-order item temperature coefficient and a high-order item temperature coefficient in the positive temperature coefficient current is eliminated; the exponential curvature compensation voltage which is not influenced by temperature drift is output, and the precision and the stability of the output voltage are improved.

The invention provides a band-gap reference circuit and a chip, and the circuit comprises a voltage generation module which is used for generating a first voltage with a positive temperature coefficient and a second voltage with a negative temperature coefficient, and generating a reference voltage with a zero temperature coefficient according to the first voltage and the second voltage; and the load driving module is used for providing load driving capability for the voltage generation module so as to carry out driving buffering on a post-stage circuit. The whole circuit does not contain an operational amplifier clamp and can provide reference voltage with a zero temperature coefficient, so that the power consumption of the band-gap reference circuit is effectively reduced; meanwhile, the load driving module provides load driving capacity for the voltage generation module, so that the output reference voltage has the load driving capacity, and the problems that an existing band-gap reference circuit is high in power consumption and does not have the load driving capacity are solved.

The invention relates to the technical field of semiconductor device manufacturing, in particular to an FRD process control method with the characteristic that forward conduction voltage drop is positive temperature, and the method comprises the following steps: S1, ring base region process, S2, cut-off ring process, S3, Control process, S4, PT sputtering, S5, Pt kill, S6, metallization, S7, irradiation treatment, S8, back thinning, and S9, back gold process. In particular, through comprehensive application of the implantation dosage of boron ions, the diffusion condition of a platinum layer and electron irradiation, the method can ensure that the FRD has optimized performance that the forward conduction voltage drop is approximate to zero temperature or the positive temperature characteristic; and the forward conduction voltage drop can be kept in a relatively stable range and can also be improved along with the temperature rise, so that the current conduction capability and the thermal stability of the parallel device are improved.

A method includes: providing a modulation circuit and a driving circuit, the modulation circuit configured to generate a temperature-dependent voltage and provide the same to the driving circuit; determined an operation mode of a memory array; providing a first current corresponding to a positive temperature coefficient by the driving circuit in response to the operation mode being a read operation on the memory array; and providing a second current corresponding to a negative temperature coefficient by the driving circuit in response to the operation mode being a write operation on the memory array.

This invention provides an optical glass, its preparation method, and an optical element. The optical glass contains the following components in molar percentage: B₂O₃: 5.0%–19.9%; SiO₂: 5.0%–28.0%; La₂O₃: 0.05%–11.5%; Gd₂O₃: 0%–10.0%; Y₂O₃: 3.6%–15.0%; ZnO: 22.5%–60.0%; the refractive index n of the optical glass is... d An Abbe number of υ is above 1.78. d The temperature coefficient of refractive index is 35-45. The optical glass of this invention has a large positive temperature coefficient of refractive index. When used in combination with optical glass having a negative temperature coefficient of refractive index, it can effectively correct temperature drift caused by rapid temperature changes or high-temperature environments, fix the focus, and maintain clear imaging. It is suitable for vehicle-mounted cameras or projectors, copiers, laser printers, and playback devices that generate a lot of heat during use.

The invention provides a delta-sigma temperature sensor of positive temperature coefficient reference voltage, the delta-sigma temperature sensor is used for obtaining a temperature value according to an input voltage, a first temperature proportionality coefficient exists between the input voltage and the temperature, the delta-sigma temperature sensor comprises a reference voltage generating circuit, an integrating circuit and a quantizer, the reference voltage generating circuit is used for generating a positive temperature coefficient reference voltage and outputting the positive temperature coefficient reference voltage to the integrating circuit, the positive temperature coefficient reference voltage is in direct proportion to the temperature and has a second temperature proportionality coefficient, and the second temperature proportionality coefficient is smaller than the first temperature proportionality coefficient; the integrating circuit is used for amplifying and accumulating a difference value between the input voltage and the positive temperature coefficient reference voltage and outputting an integral output signal; the quantizer is configured to output a bitstream according to the integrated output signal.

An over-current protection device includes a first metal layer, a second metal layer and a heat-sensitive layer laminated therebetween. The heat-sensitive layer exhibits a positive temperature coefficient (PTC) characteristic and includes a first polymer and a conductive filler. The first polymer consists of polyvinylidene difluoride (PVDF), and PVDF exists in different phases such as α-PVDF, β-PVDF and γ-PVDF. The total amount of α-PVDF, β-PVDF and γ-PVDF is calculated as 100%, and the amount of α-PVDF accounts for 48% to 55%. The conductive filler has a metal-ceramic compound.

The present disclose provides a sol-gel paste composition of matter that is provided for application to a substrate to form an electrically conductive coating which can be used, for example, as a resistor in a thick-film resistive heater, which a positive temperature coefficient of resistivity (PTCR) as a consequence of the electronic properties of the electrically conductive semiconductors used in the resistor layer and which exhibits self-limiting behavior at elevated temperatures. The composition includes a sol gel solution in which up to 90% by weight (wt. %) of the solution is comprised of conductive and insulative powders in a uniform stable solution.

The invention discloses a new energy automobile battery multi-dimensional fault diagnosis early warning system, and relates to the technical field of battery management, and the system comprises the steps: carrying out the temperature detection, current detection and voltage detection of a plurality of batteries in a battery pack, and obtaining a temperature array, a current array and a voltage array; operating temperature is generated, a theoretical temperature array is obtained, the difference value between the theoretical temperature array and the temperature array is calculated, and a temperature difference array is obtained; screening the temperature difference arrays to obtain a negative temperature difference array and a positive temperature difference array, and calculating and analyzing battery hidden trouble fault factors to obtain open circuit and short circuit hidden trouble fault factors; and calculating and analyzing battery hidden trouble fault factors of the battery pack to obtain current hidden trouble fault factors and voltage hidden trouble fault factors, determining hidden trouble fault factors in combination with circuit break and short circuit hidden trouble fault factors, carrying out fault diagnosis, and carrying out judgment and early warning. The technical problem that in the prior art, the early warning capacity is insufficient when a new energy automobile battery is charged is solved, and the technical effect of improving the charging safety is achieved.

A heater element 1 includes: a honeycomb structure 10 having an outer peripheral wall 100 and partition walls 110, the partition walls 110 defining a plurality of cells 101a, each of the cells 101a extending from a first end face 10a to a second end face 10b of the honeycomb structure 10 to form a flow path, at least the partition walls 101 being made of a material having a positive temperature coefficient (PTC) property; a first electrode 11 and a second electrode 12 provided on the first end face 10a and the second end face 10b, respectively; and a first metal terminal 13 and a second metal terminal 14 provided on the first electrode 11 and the second electrode 12, respectively, wherein at least one of the first metal terminal 13 and the second metal terminal 14 has a plurality of partial electrodes 15.

The utility model is suitable for the technical field of PTC (Positive Temperature Coefficient) electric heaters, and provides a temperature control device of a ceramic PTC electric heater, which comprises a base, the wire holder is arranged above the base, and the thermal insulation layer is arranged on the inner surface of the wire holder; the heat conduction pipe is arranged in the middle of the wire holder, a heat conduction cavity is formed in the heat conduction pipe, and a PTC heating core is arranged in the heat conduction cavity; the positioning plates are arranged on the two sides of the heat conduction pipe; according to the device, the wire holder and parts inside the wire holder are effectively protected, the damping and springback capability of the device is enhanced, and the protection performance and the stable working capability of the device in a vibration environment are remarkably improved; meanwhile, the environment temperature is monitored in real time through the temperature sensor, and the heater is controlled through the controller, so that the purpose of automatically controlling the temperature is achieved, and the long service life of the equipment is ensured; by means of the design, the stable working state of the device is kept, and the protection performance and the stable working capacity of the device in the high-temperature environment are improved.

The application discloses a DC-DC converter circuit based on over-temperature protection threshold adjustment, and an over-temperature detection module comprises: a first transistor circuit, the base of the transistor is connected with the reference voltage VBG output end of a band gap reference module, a positive temperature coefficient voltage proportional to absolute temperature is generated; a voltage dividing circuit input end is connected with the positive temperature coefficient voltage output end, the positive temperature coefficient voltage is divided to generate a detection voltage; a second transistor circuit, the base of the transistor is connected with the detection voltage output end, an over-temperature protection signal OTP is output to shut down the main circuit of the converter; an adjustment resistance circuit receives a digital adjustment signal; the digital adjustment signal changes the voltage dividing ratio of the positive temperature coefficient voltage divided to the detection voltage by controlling the equivalent resistance value of the adjustment resistance circuit; the change direction of the voltage dividing ratio is opposite to the change direction of the reference voltage VBG caused by adjustment. The application significantly improves the accuracy, consistency and overall reliability of the over-temperature protection threshold.

A positive temperature coefficient (PTC) heater apparatus is provided. The PTC heater apparatus includes a PTC heater, a resistance temperature detector (RTD) sensor mounted to the PTC heater and a controller logic unit electrically connected to the RTD sensor to receive readings of the RTD sensor, which, when the PTC heater is powered on, indicate whether the PTC heater is faulty.

The utility model discloses a PTC (Positive Temperature Coefficient) heating assembly which comprises a non-metal shell which comprises a first cavity; the heating part is arranged in the first cavity, the heating part and the non-metal shell are arranged in a spaced mode in the first direction, the heating part comprises a metal shell and a plurality of installation cavities, a flow channel is formed between the metal shell and the non-metal shell, the installation cavities are enclosed in the metal shell to form a second cavity in the second direction, the installation cavities are not parallel, and the flow channel is communicated with the flow channel. Each mounting cavity extends along a third direction; and each heating assembly is correspondingly arranged in the corresponding mounting cavity. According to the utility model, the space occupied by the heating assembly can be reduced, and meanwhile, a good heating effect can be kept. The utility model further provides the pool.

The present disclose provides a sol-gel paste composition of matter that is provided for application to a substrate to form an electrically conductive coating which can be used, for example, as a resistor in a thick-film resistive heater, which a positive temperature coefficient of resistivity (PTCR) as a consequence of the electronic properties of the electrically conductive semiconductors used in the resistor layer and which exhibits self-limiting behavior at elevated temperatures. The composition includes a sol gel solution in which up to 90% by weight (wt. %) of the solution is comprised of conductive and insulative powders in a uniform stable solution.