Sheet-shaped temperature and pressure integrated sensor and packaging method thereof

Abstract

The invention provides a sheet-shaped temperature and pressure integrated sensor and a packaging method thereof, and belongs to the technical field of sensors. The sheet-shaped temperature and pressure integrated sensor comprises a PCB, a surface-mounted thermistor and a voltage acquisition sheet. The surface-mounted thermistor is arranged on the front surface of the PCB, the voltage acquisition sheet is arranged on the front surface of the PCB and is provided with a windowing area, the surface-mounted thermistor is positioned on the PCB in the windowing area, and the temperature acquisition circuit used for transmitting data acquired by the surface-mounted thermistor is not in contact with the voltage acquisition sheet. The voltage acquisition piece further comprises an extending claw, the PCB further comprises a fixing hole, and the extending claw extends into the fixing hole to achieve mechanical interlocking of the voltage acquisition piece and the PCB. According to the application, the extension claws are matched with the fixing holes, so that the pull-off resistance of the nickel sheet is enhanced, and the nickel sheet is prevented from falling off due to temperature stress; meanwhile, the windowing area provides a protection and heat dissipation channel for the SMD thermistor, the temperature measurement precision is ensured, and the reliability and the stability of the sensor are remarkably improved.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a chip-shaped thermo-pressure integrated sensor and its packaging method. Background Technology

[0002] Integrated temperature and pressure sensors are widely used in automotive, industrial control, and consumer electronics fields to simultaneously monitor the temperature and pressure of the environment or medium. Traditional discrete sensors occupy a large space and are complex to assemble. Therefore, integrated chip sensors that integrate temperature-sensitive elements (such as surface-mount thermistors) and pressure-sensing elements (such as nickel plates) on the same PCB board have become a development trend.

[0003] However, a significant technical challenge exists in the current design and manufacturing process of integrated sensors: under conditions of simultaneous temperature and pressure detection, sensors often face complex environmental stresses, particularly drastic temperature changes and mechanical vibrations. The solder joints used to connect the pressure sensing nickel plate to the PCB board are highly susceptible to cold solder joints or even detachment after prolonged service. Soldering failure not only leads to signal transmission interruptions and abnormal data acquisition but can also cause the entire sensor to lose its functionality, severely impacting its reliability and lifespan.

[0004] Analysis revealed that the soldering failure was caused by multiple factors. First, the pressure sensing nickel sheet is typically fixed to the PCB board via surface mounting or simple pad connections. Its bonding with the PCB board relies heavily on the mechanical strength of the solder joints. However, there is a significant difference in solderability between the nickel sheet material (such as pure nickel or nickel alloy) and the PCB pads (usually copper-coated). Improper soldering process control can easily lead to voids or weak solder joints. Under temperature stress, the mismatch in the coefficients of thermal expansion between the nickel sheet, the PCB board (materials such as FR-4), and the solder generates significant shear stress. Long-term exposure leads to solder joint fatigue, microcrack initiation and propagation, ultimately resulting in a cold solder joint. Second, the overly compact layout of the temperature sensing circuit and the pressure sensing nickel sheet within a limited space, coupled with insufficient physical isolation between solder joints, easily accelerates solder joint failure due to stress concentration. Furthermore, the connection points between the external leads and the PCB board are often weak points where stress concentration occurs. When the sensor as a whole is bent or stretched, the deformation at the connection points is transmitted to adjacent nickel sheet solder joints, further exacerbating the risk of a cold solder joint.

[0005] Therefore, how to provide a robust, effective, and adaptable integrated thermo-baric sensor has become a pressing technical problem to be solved in this field. Summary of the Invention

[0006] The purpose of this application is to provide a chip-shaped integrated temperature and pressure sensor and its packaging method, including: PCB board; A surface-mount thermistor is disposed on the front side of the PCB board; A voltage acquisition chip is disposed on the front side of the PCB board; the voltage acquisition chip has a window area, and the surface mount thermistor is disposed on the PCB board within the window area; The temperature acquisition circuit used to transmit the data acquired by the surface-mount thermistor is not in contact with the voltage acquisition chip. The voltage acquisition chip also includes: an extension claw; The PCB board further includes: a fixing hole; the extension claw extends into the fixing hole to fix and encapsulate the voltage acquisition chip onto the PCB board.

[0007] In one embodiment, the window area is a wraparound window or a three-sided enclosed window.

[0008] In one embodiment, the window area is a three-sided enclosed window; The temperature acquisition circuit includes positive and negative temperature acquisition solder joints, positive and negative connecting lines, and positive and negative temperature connection solder joints. The positive and negative temperature acquisition solder joints are located within the window area; The positive and negative connecting lines extend from the window area; The positive and negative temperature connection solder joints are located outside the window area.

[0009] In one embodiment, the voltage acquisition chip further includes a protrusion located in the window area; the protrusion is bent upward relative to the extension plane of the voltage acquisition chip and then extends parallel to the extension plane of the voltage acquisition chip toward the location of the surface mount thermistor; the protrusion is used to protect the surface mount thermistor. The extended claw bends downward relative to the extension plane of the voltage acquisition chip.

[0010] In one embodiment, a partition area is provided on the PCB board, the partition area being located between the positive and negative temperature connection solder joints, for physically isolating the positive and negative poles of the positive and negative temperature connection solder joints; the extension length of the partition area is equal to the extension length of the positive and negative temperature connection solder joints.

[0011] In one embodiment, the integrated sheet-like temperature and pressure sensor further includes: A first encapsulating adhesive is disposed on the PCB board to encapsulate the surface mount thermistor within the window area. The second encapsulating adhesive is applied to the PCB board to encapsulate the positive and negative temperature connection solder joints and the pressure connection solder joints in the voltage acquisition circuit. The third encapsulating adhesive is applied to the PCB board and is used to encapsulate other circuit structures exposed on the PCB board.

[0012] In one embodiment, the overall length of the PCB board is L, the distance from the center of the positive and negative temperature connection solder joint to the first edge of the PCB board is L1, and the distance from the center of the positive and negative temperature connection solder joint to the second edge of the PCB board is L2. The first edge is the edge close to the external lead and satisfies: 12±0.3mm≤L≤16±0.3mm, and 3:7≤L1:L2≤5:5.

[0013] This application also provides a packaging method for a chip-shaped integrated temperature and pressure sensor, which utilizes the chip-shaped integrated temperature and pressure sensor described in any of the above embodiments, and includes the following steps: S1, a PCB board is provided, on which a fixing hole, a temperature acquisition circuit and a voltage acquisition circuit are pre-set, the fixing hole is set on the path of the voltage acquisition circuit, and the inner sidewall of the fixing hole is covered with copper material; S2, provides a voltage acquisition chip, the voltage acquisition chip having a windowed area and an extended claw; S3, Solder paste is provided in the fixing hole, and the extension claw is inserted into the fixing hole to fix the voltage acquisition chip to the front side of the PCB board by soldering; S4, a surface-mount thermistor is provided, and the surface-mount thermistor is placed in the window area and electrically connected to the temperature acquisition circuit; S5, the voltage acquisition chip and the surface mount thermistor are encapsulated on the PCB board using encapsulating adhesive.

[0014] In one embodiment, step S2 is followed by: The extension claws and protrusions of the voltage acquisition chip are pre-shaped, so that the extension claws are bent downward relative to the extension plane of the voltage acquisition chip, and the protrusions are bent upward relative to the extension plane of the voltage acquisition chip and then extend along the extension plane of the voltage acquisition chip toward the location of the surface mount thermistor.

[0015] In one embodiment, step S5 specifically includes: S51, apply the first encapsulating adhesive to encapsulate the surface mount thermistor within the window area; S52, apply a second encapsulating adhesive to encapsulate the positive and negative temperature connection solder joints in the temperature acquisition circuit and the pressure connection solder joints in the voltage acquisition circuit; S53, apply a third encapsulating adhesive to encapsulate other circuit structures exposed on the PCB board.

[0016] The integrated thermo-baric sensor of this application has at least the following advantages or beneficial effects: 1. The integrated temperature and pressure sensor provided in this application includes: a PCB board, a surface-mount thermistor, and a voltage acquisition chip. The PCB board includes mounting holes. The voltage acquisition chip includes a window area and an extension claw. By adding a mechanical anchoring structure between the extension claw and the mounting holes, the problem of the voltage acquisition chip relying solely on solder joints for load-bearing in traditional designs is fundamentally solved. When the sensor is subjected to mechanical vibration or external lead tension, the extension claw, as an independent physical anchor point, directly bears and buffers most of the mechanical stress, transforming the solder joint from a "main load-bearing structure" to an auxiliary role "only responsible for electrical conduction." This effectively avoids the problems of poor soldering and detachment of solder joints caused by stress concentration as described in the background art, and greatly enhances the sensor's vibration and tensile resistance under complex working conditions.

[0017] Meanwhile, this structure cleverly mitigates solder joint fatigue failure caused by mismatched thermal expansion coefficients of the materials. During drastic temperature changes, the extended claws can generate micro-movements within the fixing holes to absorb thermal stress and prevent its transmission to the solder joints. Combined with the physical isolation design of the windowed area, mutual interference between the voltage acquisition chip and the surface-mount thermistor is avoided. This composite fixing method, which prioritizes mechanical anchoring and supplements it with electrical welding, not only reduces the process requirements for the solderability of the nickel sheet material but also systematically improves the long-term reliability and service life of the sensor in harsh temperature environments from a structural mechanics perspective.

[0018] More specifically: (1) By setting the cooperative structure of the extension claw and the fixing hole, the mechanical interlock between the voltage acquisition chip and the PCB board is realized. Specifically, after the extension claw extends into the fixing hole, it not only increases the contact area between the nickel sheet and the PCB board, but also forms a physical fixing effect similar to anchoring. When the encapsulating glue is filled in the subsequent process, the encapsulating glue can flow into the fixing hole to wrap the extension claw, and after curing, it forms a firm glue nail structure. This synergistic effect of mechanical interlock and adhesive significantly enhances the pull-out resistance of the voltage acquisition chip. Even when the temperature changes drastically and the thermal expansion coefficients are mismatched, resulting in internal stress, it can effectively prevent the nickel sheet from shifting or falling off, thereby ensuring the long-term stability of the pressure signal acquisition. (2) The setting of the window area can, on the one hand, protect the surface mount thermistor and avoid the failure of the surface mount thermistor caused by the deformation of the encapsulating glue. On the other hand, it can provide a heat dissipation channel to avoid the surface mount thermistor sensing temperature from being inconsistent with the actual temperature of the test site.

[0019] 2. The integrated temperature and pressure sensor provided in this application, by setting the window area as a surround-type or three-sided enclosed window, provides ample installation space for the surface-mount thermistor while ensuring the integrity of the main structure of the voltage acquisition chip. The surround-type or three-sided enclosed structure allows the surface-mount thermistor to be partially or fully surrounded by the nickel sheet. On the one hand, the rigidity of the nickel sheet itself provides physical protection for the internal surface-mount thermistor, resisting external mechanical impacts. On the other hand, this open design facilitates the full flow and filling of the encapsulating adhesive around the surface-mount thermistor, achieving dead-angle potting and avoiding stress concentration or sealing failure caused by local cavitation, further improving the encapsulation reliability of the temperature acquisition unit.

[0020] 3. The integrated surface-mount temperature and pressure sensor provided in this application achieves spatial decoupling of key components by segmenting the temperature acquisition circuit 12. Specifically, the susceptible positive and negative temperature acquisition solder joints are located inside the window area, while the positive and negative temperature connection solder joints for external leads are located outside the window area and connected via positive and negative connecting wires. This layout ensures that the surface-mount thermistor and its solder joints within the window area are individually protected by encapsulating adhesive, preventing them from being affected by external stress. The connection solder joints outside the window area can be independently soldered or re-encapsulated, avoiding interference from the flow of encapsulating adhesive on the electrical connection of the solder joints. The through-wire design acts as a stress buffer; when the external leads are pulled, the stress is mainly concentrated on the connection solder joints and is not directly transmitted to the internal surface-mount thermistor solder joints, effectively protecting the core temperature sensing element.

[0021] 4. The integrated temperature and pressure sensor provided in this application achieves multi-functional integration through three-dimensional molding of the voltage acquisition chip. The protrusion bends upward and extends towards the surface-mount thermistor, forming a protective cover above the surface-mount thermistor. This not only provides physical buffer space for the fragile surface-mount thermistor without adding additional components, preventing external objects from directly impacting the surface-mount thermistor during subsequent assembly, but also guides the encapsulating adhesive (first encapsulating adhesive) to evenly cover the surface during potting, preventing the adhesive from overflowing into non-target areas. The downward-bending extension claws allow for smoother insertion into the fixing hole, facilitating automated assembly. Simultaneously, the downward-bending extension claws form a hook-shaped contact shape in the fixing hole, further enhancing the mechanical gripping force and electrical conductivity with the hole wall and internal solder paste and copper material, ensuring stable transmission of the voltage acquisition signal.

[0022] 5. The integrated temperature and pressure sensor provided in this application adopts a three-layer regional encapsulation structure, achieving functional zoning and stress decoupling: 1) The first encapsulating adhesive is specifically used to encapsulate the surface-mount thermistor in the window area. It uses a material with good flowability and low stress, ensuring that the surface-mount thermistor operates under stress-free conditions, and that temperature measurement accuracy is not affected by encapsulation stress. 2) The second encapsulating adhesive is specifically used to encapsulate the positive and negative temperature connection solder joints and the pressure connection solder joints. It uses a high-strength, high-adhesion material to provide strong fixation for the solder joints bearing mechanical stress and electrical connections, preventing fatigue cracking of the solder joints during vibration or thermal cycling. 3) The third encapsulating adhesive, as the outermost layer of overall protection, can cover the exposed positive and negative connection lines and pressure acquisition solder joints, and can further encapsulate the first and second encapsulating adhesives, forming a seamless waterproof and dustproof barrier. This layered design avoids the contradiction of a single encapsulating adhesive being unable to simultaneously achieve low stress and high strength. Furthermore, when one layer fails, the other layers can still provide protection, significantly extending the overall lifespan of the sensor. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of the integrated temperature and pressure sensor provided in the embodiments of this application; Figure 2 for Figure 1 A schematic diagram of the PCB board structure in the integrated temperature and pressure sensor provided in the embodiment shown; Figure 3 for Figure 1 A schematic diagram of the voltage acquisition chip in the integrated temperature and pressure sensor provided in the embodiment shown; Figure 4 for Figure 1 The embodiment shown is a schematic diagram of the structure of the sheet-like thermo-baric integrated sensor after encapsulation with the first encapsulating adhesive; Figure 5 for Figure 1 The illustrated embodiment provides a top front view of the packaged integrated thermo-baric sensor. Figure 6 for Figure 1 The embodiment shown is a top view of the back of the packaged integrated thermo-baric sensor.

[0025] icon: 100-type integrated temperature and pressure sensor: PCB board 10: Mounting hole 11, temperature acquisition circuit 12, positive and negative temperature acquisition solder joints 12a: positive temperature acquisition solder joint 12a1, negative temperature acquisition solder joint 12a2; positive and negative connection lines 12b: positive connection line 12b1, negative connection line 12b2; positive and negative temperature connection solder joints 12c: positive temperature connection solder joint 12c1, negative temperature connection solder joint 12c2; voltage acquisition circuit 13, pressure acquisition solder joint 13a, pressure connection solder joint 13b, blocking ink 14, isolation area 15; Surface mount thermistor 20; Voltage acquisition chip 30: windowed area 31, protrusion 32, extension claw 33; External leads 40: Temperature acquisition external lead 41, voltage acquisition external lead 42; First encapsulant 51, second encapsulant 52, third encapsulant 53; The bottom layer is silkscreened with 61. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0029] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0030] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] Please see Figure 1 This application provides a chip-type integrated temperature and pressure sensor 100, including: a PCB board 10, a surface mount thermistor 20, and a voltage acquisition chip 30.

[0033] PCB board 10, also known as printed circuit board, can be rigid or flexible. From a physical structure perspective, PCB board 10 can include, from bottom to top, the following layers: bottom silkscreen (if there is text, it can be marked on the bottom silkscreen layer. If there is no text, the bottom silkscreen layer can be omitted), bottom solder mask (green paint), bottom copper foil (circuit), substrate (insulating layer), top copper foil (circuit), top solder mask (green paint), and top silkscreen (white text).

[0034] A surface-mount thermistor 20 is disposed on the front side of the PCB board 10. The surface-mount thermistor 20 may comprise a semiconductor ceramic material (such as a transition metal oxide sintered body) or a polymeric PTC composite material. More specifically, the surface-mount thermistor 20 includes a resistor chip, surface electrodes, an insulating layer, and external electrodes. The resistor chip may be a planar surface-mount thermistor body. The surface electrodes may be a pair of electrodes respectively covering most of the upper and lower surfaces of the chip and extending around the sides to the other side, but insulated from each other. The insulating layer may be coated on the electrode surfaces, with only the ends exposed for connection. External electrodes are formed at both ends of the component, electrically connected to the exposed portions of the surface electrodes, and may extend to cover a portion of the main surface to increase the soldering area.

[0035] Please see Figure 3 The voltage acquisition chip 30 is disposed on the front side of the PCB board 10. The voltage acquisition chip 30 can be a nickel sheet. In some embodiments, the voltage acquisition chip 30 may include: a first substrate portion and a second substrate portion, both of which are nickel sheet bodies, used to carry voltage signals and provide mechanical support. The first substrate portion is... Figure 1A voltage acquisition chip 30 located outside the PCB board 10 is used for electrical connection with the energy storage battery whose voltage is to be tested. A second substrate is disposed on the front side of the PCB board 10. The second substrate includes: a window area 31, a protrusion 32, and an extension claw 33. The window area 31 can be configured as a surrounding or three-sided enclosed window to accommodate a surface mount thermistor 20 (i.e., the surface mount thermistor 20 is disposed on the PCB board 10 within the window area 31), achieving integrated temperature and pressure control. The window area 31 serves two purposes: firstly, it protects the surface mount thermistor 20, preventing failure caused by deformation of the encapsulating adhesive; secondly, it provides a heat dissipation channel, preventing discrepancies between the temperature sensed by the surface mount thermistor 20 and the actual temperature at the test site. In one embodiment, the window area 31 is circular, rectangular (square and oblong), other polygonal, or other shapes. The protrusion 32 is located in the window area 31, bends upward and extends parallel to protect the surface mount thermistor, and guides the flow of the encapsulating adhesive. The PCB board 10 also includes mounting holes 11. The number of mounting holes 11 is at least one, but can be two, three, or other numbers. The number and position of the mounting holes 11 correspond to the number and position of the extension claws 33 provided on the nickel sheet in the windowed area, respectively. The extension claws 33 extend from the edge of the substrate where the windowed area of ​​the second substrate is located, bend downwards, and extend into the mounting holes 11 of the PCB board 10 to achieve mechanical anchoring. Subsequent soldering and encapsulation are then performed to fix and encapsulate the voltage acquisition piece 30 onto the PCB board 10. The second substrate also has a soldering surface for soldering to the PCB board 10. This soldering surface is soldered to the copper foil (circuit) located on the PCB board 10 to achieve electrical connection.

[0036] The temperature acquisition circuit 12, used to transmit data collected by the surface-mount thermistor 20, does not contact the voltage acquisition chip 30. If the window area 31 is configured as a surround window, the edge of one window of the voltage acquisition chip 30 can be configured as an upward-protruding structure to avoid the temperature acquisition circuit 12 disposed on the surface of the PCB board 10; alternatively, the temperature acquisition circuit 12 disposed on the surface of the PCB board 10 can be disposed at a lower position, so that there is a height difference (suspended space) between the temperature acquisition circuit 12 and the voltage acquisition chip 30, thereby achieving non-contact between the temperature acquisition circuit 12 and the voltage acquisition chip 30. If the window area 31 is configured as a three-sided surround window, after the temperature acquisition circuit 12 is electrically connected to the surface-mount thermistor 20, it extends outward through the fourth cutout, achieving non-contact with the voltage acquisition chip 30.

[0037] In the above embodiments of this application, a mechanical interlock between the voltage acquisition piece 30 and the PCB board 10 is achieved by setting a mating structure between the extension claw 33 and the fixing hole 11. Specifically, after the extension claw 33 extends into the fixing hole 11, it not only increases the contact area between the nickel sheet and the PCB board, but also forms a physical fixing effect similar to anchoring. During subsequent encapsulation, the encapsulation adhesive can flow into the fixing hole 11 to wrap the extension claw 33, forming a firm adhesive nail structure after curing. This synergistic effect of mechanical interlocking and adhesive significantly enhances the pull-out resistance of the voltage acquisition piece 30. Even when drastic temperature changes cause a mismatch in the coefficient of thermal expansion, resulting in internal stress, it can effectively prevent the nickel sheet from shifting or falling off, thereby ensuring the long-term stability of pressure signal acquisition.

[0038] In one embodiment, the window area 31 is a wraparound window or a three-sided enclosed window.

[0039] In this embodiment, by setting the window area 31 as a surround window or a three-sided enclosed window, sufficient installation space is provided for the surface-mount thermistor 20 while ensuring the integrity of the main structure of the voltage acquisition chip 30. The surround or three-sided enclosed structure allows the surface-mount thermistor to be partially or fully surrounded by the nickel sheet. On the one hand, the rigidity of the nickel sheet itself provides physical protection for the internal surface-mount thermistor, resisting external mechanical impacts. On the other hand, this open design facilitates the full flow and filling of the encapsulating adhesive around the surface-mount thermistor, achieving dead-angle potting and avoiding stress concentration or sealing failure caused by local cavitation, further improving the encapsulation reliability of the temperature acquisition unit.

[0040] Please see Figure 1 , Figure 2 and Figure 3 In one embodiment, the window area 31 is a three-sided enclosed window. The temperature acquisition circuit 12 includes positive and negative temperature acquisition solder joints 12a, positive and negative connecting lines 12b, and positive and negative temperature connection solder joints 12c. The positive and negative connecting lines 12b are electrically connected to the positive and negative temperature acquisition solder joints 12a and 12c, respectively. The positive and negative temperature acquisition solder joints 12a are located within the window area 31. The positive and negative connecting lines 12b extend out of the window area 31. The positive and negative temperature connection solder joints 12c are located outside the window area 31.

[0041] In this embodiment, the temperature acquisition circuit 12 is segmented to achieve spatial decoupling of key components. Specifically, the susceptible positive and negative temperature acquisition solder joints 12a are located inside the window area 31, while the positive and negative temperature connection solder joints 12c for external leads are located outside the window area 31 and connected via positive and negative connection lines 12b. This layout ensures that the surface-mount thermistor 20 and its solder joints inside the window area 31 are individually protected by encapsulant, preventing them from being affected by external stress. The connection solder joints outside the window area 31 can be independently soldered or re-encapsulated, avoiding interference from the flow of encapsulant on the electrical connection of the solder joints. The through-line design of the positive and negative connection lines 12b acts as a stress buffer. When the external leads are pulled, the stress is mainly concentrated on the positive and negative temperature connection solder joints 12c, and will not be directly transmitted to the internal positive and negative temperature acquisition solder joints 12a, effectively protecting the core temperature sensing element.

[0042] In one embodiment, such as Figure 2 As shown, the positive and negative temperature acquisition solder joints 12a include positive temperature acquisition solder joint 12a1 and negative temperature acquisition solder joint 12a2, which are arranged at intervals. The positive and negative connecting lines 12b include positive connecting lines 12b1 and negative connecting lines 12b2, which are arranged at intervals. The positive and negative temperature connection solder joints 12c include positive temperature connection solder joint 12c1 and negative temperature connection solder joint 12c2, which are arranged at intervals. The positive temperature acquisition solder joint 12a1 and the positive temperature connection solder joint 12c1 are electrically connected through the positive connecting line 12b1. The negative temperature acquisition solder joint 12a2 and the negative temperature connection solder joint 12c2 are electrically connected through the negative connecting line 12b2. Figure 2 The positive temperature acquisition solder joint 12a1, positive connection line 12b1, and positive temperature connection solder joint 12c1 (i.e., the positive terminal of the temperature acquisition circuit 12) are positioned between the negative temperature acquisition solder joint 12a2, negative connection line 12b2, negative temperature connection solder joint 12c2 (i.e., the negative terminal of the temperature acquisition circuit 12) and the voltage acquisition circuit 13. The voltage acquisition circuit 13 is positioned in three directions in the peripheral area of ​​the temperature acquisition circuit 12.

[0043] In other embodiments, the negative temperature acquisition solder joint 12a2, negative connection line 12b2, and negative temperature connection solder joint 12c2 (i.e., the negative terminal of the temperature acquisition circuit 12) can also be disposed between the positive temperature acquisition solder joint 12a1, positive connection line 12b1, positive temperature connection solder joint 12c1 (i.e., the positive terminal of the temperature acquisition circuit 12) and the voltage acquisition circuit 13. The voltage acquisition circuit 13 is disposed in three directions in the peripheral area of ​​the temperature acquisition circuit 12.

[0044] In one embodiment, the voltage acquisition chip 30 further includes a protrusion 32 located in the window region 31. The protrusion 32 bends upward relative to the extension plane of the voltage acquisition chip 30 and then extends parallel to the extension plane of the voltage acquisition chip 30 toward the location of the surface mount thermistor 20. The protrusion 32 is used to protect the surface mount thermistor 20. An extension claw 33 bends downward relative to the extension plane of the voltage acquisition chip 30.

[0045] In this embodiment, multiple functions are integrated by three-dimensionally molding the voltage acquisition chip 30. The protrusion 32 bends upward and extends towards the surface mount thermistor 20, forming a protective cover above the surface mount thermistor. This not only provides a physical buffer space for the fragile surface mount thermistor without adding extra components, preventing external objects from directly impacting the surface mount thermistor during subsequent assembly, but also guides the encapsulating adhesive (such as...) during potting. Figure 4 The first encapsulating adhesive 51 shown is evenly applied to prevent it from overflowing into non-target areas. The downward-bending design of the extension claw 33 allows it to be inserted more smoothly into the fixing hole 11, facilitating automated assembly. At the same time, the downward-bending extension claw forms a hook-shaped contact pattern in the fixing hole, further enhancing the mechanical engagement and electrical conductivity with the hole wall and internal solder paste and copper material, ensuring stable transmission of voltage acquisition signals.

[0046] Since the surface-mount thermistor 20 is used to collect temperature data, while the voltage acquisition chip 30 is packaged on the PCB board surrounding the surface-mount thermistor, when the battery is charged and discharged at a high current, although the voltage acquisition chip 30 itself does not generate heat, the copper busbar or busbar connected to it may generate heat. The heat is conducted to the surface-mount thermistor through the copper foil on the PCB board, causing the temperature acquisition reading to be lagging or too high, and thus failing to accurately reflect the temperature of the battery cell itself.

[0047] In one embodiment, a thermal isolation groove or a cutout window is provided on the copper foil of the PCB board between the pads (positive and negative temperature acquisition solder joints 12a) of the surface mount thermistor 20 and the pads (pressure acquisition solder joints 13a) of the voltage acquisition piece 30. The thermal isolation groove is the exposed substrate area after the copper foil is removed, used to block the rapid conduction of heat through the copper foil, ensuring the accuracy and response speed of temperature acquisition.

[0048] In this embodiment, by physically blocking the heat conduction path of the copper foil, the surface-mount thermistor mainly senses the ambient temperature (cell temperature), reducing heat conduction interference from the metal parts at the voltage acquisition end and improving temperature control accuracy.

[0049] In one embodiment, such as Figure 2As shown, a partition region 15 is provided on the PCB board 10. The partition region 15 is located between the positive and negative temperature connection solder joints 12c, and is used to physically isolate the positive and negative electrodes of the positive and negative temperature connection solder joints 12c. The extension length of the partition region 15 is equal to the extension length of the positive and negative temperature connection solder joints 12c. A blocking ink 14 is also provided on the PCB board 10. The blocking ink 14 is located between the positive and negative temperature acquisition solder joints 12a, and is used to electrically isolate the positive and negative electrodes of the positive and negative temperature acquisition solder joints 12a.

[0050] This solution constructs a double short-circuit barrier by setting up an isolation area 15 and blocking ink 14, achieving insulation of the temperature acquisition circuit: 1) The isolation area 15 is located between the positive and negative temperature connection solder joints 12c, and the positive and negative solder joints are completely separated by physical hollowing or slotting. This physical isolation ensures that even under conditions of high humidity, high voltage, or impurity contamination leading to a decrease in surface insulation resistance, a leakage path cannot be formed between the positive and negative electrodes through the PCB substrate surface, eliminating the risk of short circuit. Its extension length is equal to the solder joint length, ensuring thorough isolation. 2) The blocking ink 14 is located between the positive and negative temperature acquisition solder joints 12a, serving as an electrical isolation layer, effectively preventing short circuits caused by ion migration or moisture erosion between adjacent solder joints when the encapsulating adhesive is not fully covered or has aged and cracked. The double isolation design significantly improves the electrical safety and long-term reliability of the sensor under harsh operating conditions. In the above embodiment, the integrated sheet temperature and pressure sensor 100 is a robust integrated sheet temperature and pressure sensor that can effectively resist encapsulating adhesive peeling and adapt to harsh operating conditions.

[0051] In one embodiment, such as Figure 5 As shown, the sheet-type integrated temperature and pressure sensor 100 further includes: a first encapsulating adhesive 51, a second encapsulating adhesive 52, and a third encapsulating adhesive 53. The first encapsulating adhesive 51, the second encapsulating adhesive 52, and the third encapsulating adhesive 53 can all be UV adhesives, or they can be different types of encapsulating adhesives.

[0052] The first encapsulant 51 is disposed on the PCB board 10 and is used to encapsulate the surface-mount thermistor 20 within the window area 31. The first encapsulant 51 can fill the gap between the extension claw 33 and the fixing hole 11 along the fixing hole 11, reinforcing the encapsulation of the voltage acquisition chip 30 and the PCB board 10. The first encapsulant 51 can be disposed only on the front side of the PCB board 10, or it can be disposed on both the front and back sides of the PCB board 10. The first encapsulant 51 disposed on the back side of the PCB board 10 needs to maintain a certain thickness and a shape parallel to the PCB board 10. The second encapsulant 52 is disposed on the PCB board 10 and is used to encapsulate the positive and negative temperature connection solder joints 12c and the pressure connection solder joints 13b in the voltage acquisition circuit 13. The second encapsulant 52 can be disposed as follows: Figure 5Multiple encapsulants are provided at intervals, meaning that each external lead and the circuit (such as positive and negative temperature connection solder joints 12c and / or pressure connection solder joints 13b) on the front side of the PCB board 10 are encapsulated with a single piece of encapsulant. The second encapsulant 52 can also be a single piece, encapsulating each external lead and its corresponding electrical connection on the front side of the PCB board 10. In this overall encapsulation, excess second encapsulant 52 can overflow through the partition area 15. The partition area 15 can completely separate the positive and negative temperature connection solder joints by physically cutting out or slotting, and can also achieve reinforced encapsulation between the PCB board 10, the temperature acquisition circuit 12, the voltage acquisition circuit 13, and the external lead 40. A third encapsulant 53 is provided on the PCB board 10 to encapsulate other circuit structures exposed on the PCB board 10. These other circuit structures include the positive and negative connection lines 12b and the pressure acquisition solder joints 13a. The third encapsulant 53 can also re-encapsulate the first encapsulant 51 and the second encapsulant 52.

[0053] In this embodiment, a three-layer, regional encapsulation structure is adopted to achieve functional zoning and stress decoupling: 1) The first encapsulating adhesive 51 is specifically used to encapsulate the surface-mount thermistor 20 within the window area 31. It is made of a material with good flowability and low stress, ensuring that the surface-mount thermistor operates under stress-free conditions, and that temperature measurement accuracy is not affected by encapsulation stress. 2) The second encapsulating adhesive 52 is specifically used to encapsulate the positive and negative temperature connection solder joints 12c and the pressure connection solder joints 13b. It is made of a high-strength, high-adhesion material, providing strong fixation for the solder joints that bear mechanical stress and electrical connections, preventing fatigue cracking of the solder joints during vibration or thermal cycling. 3) The third encapsulating adhesive 53 serves as the outermost layer of overall protection, covering the exposed positive and negative connection lines 12b and the pressure acquisition solder joint 13a. It can also re-encapsulate the first and second encapsulating adhesives 51 and 52, forming a seamless waterproof and dustproof barrier. This layered design avoids the contradiction of a single encapsulating adhesive being unable to simultaneously achieve low stress and high strength. Furthermore, when one layer fails, the other layers can still provide protection, significantly extending the overall lifespan of the sensor.

[0054] In one embodiment, such as Figure 5 As shown, the overall length of the PCB board 10 is L. The distance from the center of the positive and negative temperature connection solder joint 12c to the first edge of the PCB board 10 is L1, and the distance from the center of the positive and negative temperature connection solder joint 12c to the second edge of the PCB board 10 is L2. The first edge is the edge closest to the external lead 40, and satisfies: 12±0.3mm≤L≤16±0.3mm, and 3:7≤L1:L2≤5:5. The external lead 40 includes a temperature acquisition external lead 41 and a voltage acquisition external lead 42. The external lead 40 and the voltage acquisition piece 30 are respectively disposed at both ends of the length direction of the PCB board 10.

[0055] In this embodiment, by precisely limiting the overall length L of the PCB board 10 and the ratio L1:L2 of the distance from the center of the connecting solder joint to the edge, the mechanical performance of the sensor is optimized: 1) Limiting L to the range of 12±0.3mm to 16±0.3mm ensures that there is sufficient space on the surface of the PCB board 10 to arrange the temperature acquisition circuit 12 and the voltage acquisition circuit 13, while avoiding the PCB board 10 being too long, which would easily bend and break during packaging and use, or the PCB board 10 being too short, which would lead to crowded component layout and poor heat dissipation. 2) Limiting L1:L2 to the range of 3:7 to 5:5 ensures that the stress concentration point of the positive and negative temperature connecting solder joint 12c is in the mechanical balance position of the PCB board. Since the external lead 40 is located at the first edge, the center of the connection solder joint is designed to be close to the middle or slightly off the lead side, so that the tensile force on the lead can be distributed more evenly on the entire PCB board 10, avoiding stress concentration at the root of the solder joint, which would cause the solder pad to lift or fall off. At the same time, it ensures that the voltage acquisition chip 30 is located at the other end, achieving dynamic balance of forces at both ends.

[0056] In one embodiment, such as Figure 6 As shown Figure 1 The illustrated embodiment provides a top view of the packaged back of the integrated thermobaric sensor. This top view shows three extending claws 33 protruding from the mounting holes 11 and encapsulated with encapsulating adhesive. The top view also shows a partition area 15 on the PCB board 10, which prevents electrical connection between the two positive and negative temperature connection solder joints 12c. The top view also shows the underlying silkscreen 61, used to mark information such as the product model and manufacturing date of the integrated thermobaric sensor 100.

[0057] This application also provides a method for fabricating a sheet-like integrated temperature and pressure sensor, applicable to the sheet-like integrated temperature and pressure sensor as described in any of the above embodiments. The method for fabricating the sheet-like integrated temperature and pressure sensor includes the following steps: S1, a PCB board 10 is provided. The PCB board 10 has a mounting hole 11, a temperature acquisition circuit 12 and a voltage acquisition circuit 13 pre-set on it. The mounting hole 11 is set on the path of the voltage acquisition circuit 13 and the inner sidewall of the mounting hole 11 is covered with copper material.

[0058] S2 provides a voltage acquisition chip 30, which has a window area 31 and an extension claw 33.

[0059] S3, solder paste is provided in the fixing hole 11, and the extension claw 33 is inserted into the fixing hole 11 to fix the voltage acquisition chip 30 to the front side of the PCB board 10 by soldering.

[0060] S4 provides a surface-mount thermistor 20, which is placed in the window area 31 and electrically connected to the temperature acquisition circuit 12.

[0061] S5, the voltage acquisition chip 30 and the surface mount thermistor 20 are encapsulated on the PCB board 10 using encapsulating adhesive.

[0062] The fabrication method of the integrated temperature and pressure sensor 100 provided in this embodiment solves the problem of difficult nickel sheet welding and improves connection reliability through an "in-hole welding" process: copper material is wrapped around the inner wall of the fixing hole 11, providing a solderable metal surface for solder paste welding. Solder paste is placed in the fixing hole 11, and then the extension claw 33 is inserted, realizing a three-dimensional welding structure of "copper material + solder paste + nickel sheet". Compared with traditional surface mount welding, this structure has a larger welding area and forms a ring-shaped solder joint, significantly improving mechanical strength. This process completes the mechanical fixing and electrical conduction of the voltage acquisition chip 30 simultaneously through a single welding process, simplifying the production process. At the same time, the welding fixation provides a firm pre-position for subsequent encapsulation, ensuring that the nickel sheet will not shift when the encapsulation adhesive is applied, thereby ensuring consistency and yield.

[0063] In one embodiment, after step S2, the method further includes: pre-forming the extension claw 33 and the protrusion 32 of the voltage acquisition piece 30, so that the extension claw 33 is bent downward relative to the extension plane of the voltage acquisition piece 30, and the protrusion 32 is bent upward relative to the extension plane of the voltage acquisition piece 30 and then extends along the extension plane of the voltage acquisition piece 30 to the location of the surface mount thermistor 20.

[0064] In this embodiment, before mounting the voltage acquisition chip 30 onto the PCB board 10, the extension claw 33 and the protrusion 32 are pre-formed, achieving process optimization of "contour assembly". The extension claw 33 is pre-bent downwards to perfectly match its shape and angle with the fixing hole 11, ensuring successful alignment in the subsequent insertion process. This avoids assembly difficulties and damage risks associated with bending operations in confined spaces, improving assembly efficiency and yield. The protrusion 32 is pre-bent upwards and extended horizontally, allowing precise control of its final position and height relative to the surface-mount thermistor 20. This ensures the protrusion 32 hovers precisely above the surface-mount thermistor, providing protection without squeezing or touching it due to insufficient bending precision. This pre-forming process guarantees the accuracy and consistency of the protective structure.

[0065] In one embodiment, step S5 specifically includes: S51, apply the first encapsulant 51 to encapsulate the surface mount thermistor 20 within the windowed area 31. The first encapsulant 51 can be a silicone potting compound or a low-stress epoxy resin potting compound to protect the surface mount thermistor 20. The first encapsulant 51 has good flowability, high thermal conductivity, and low stress.

[0066] S52, apply the second encapsulating adhesive 52 to encapsulate the positive and negative temperature connection solder joints 12c in the temperature acquisition circuit 12 and the pressure connection solder joints 13b in the voltage acquisition circuit 13. The second encapsulating adhesive 52 can be an epoxy resin potting compound, used to fix the solder joints including the positive and negative temperature connection solder joints 12c and the pressure connection solder joints 13b. The second encapsulating adhesive 52 has high adhesion, high strength, and high heat resistance.

[0067] S53, apply the third encapsulant 53 to encapsulate other circuit structures exposed on the PCB board 10. The third encapsulant 53 can be a silicone potting compound, used to achieve overall protection of structural components on the PCB board 10. The third encapsulant 53 is not prone to yellowing and is suitable as a final protective layer. It has excellent waterproof and dustproof functions and is repairable.

[0068] In this embodiment, a three-layer encapsulation process is employed to achieve precise control over encapsulation quality: 1) First, a first encapsulation adhesive 51, such as silicone potting compound or low-stress epoxy resin potting compound, is applied to encapsulate the surface-mount thermistor 20. Utilizing its good flowability, high thermal conductivity, and low stress, this ensures the surface-mount thermistor is stress-free and efficiently conducts heat, while the adhesive fully fills the tiny gaps in the window area 31. 2) After the first encapsulation adhesive 51 has initially cured, a second encapsulation adhesive 52, such as epoxy resin potting compound, is applied to encapsulate the solder joints. Utilizing its high adhesion, high strength, and high heat resistance, this firmly fixes the solder joints that bear mechanical stress, while preventing performance degradation due to mixing with the first layer of adhesive. 3) Finally, a third encapsulation adhesive 53, such as silicone potting compound, is applied for overall protection. Utilizing its resistance to yellowing, waterproofing, dustproofing, and repairability, a continuous and dense protective film is formed, covering all exposed circuitry and re-encapsulating the first two layers of adhesive, eliminating any gaps that may exist at the interlayer interfaces. This step-by-step encapsulation process, which starts with localized encapsulation and then proceeds to the overall encapsulation, avoids problems such as bubbles, delamination, and stress concentration that may occur with a single large-volume encapsulation. It ensures that each layer of encapsulating adhesive can perform at its best, ultimately forming a highly reliable and long-life composite encapsulation.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A chip-shaped integrated temperature and pressure sensor, comprising: PCB board (10); A surface-mount thermistor (20) is disposed on the front side of the PCB board (10); A voltage acquisition chip (30) is disposed on the front side of the PCB board (10); the voltage acquisition chip (30) has a window area (31), and the surface mount thermistor (20) is disposed on the PCB board (10) within the window area (31); The temperature acquisition circuit (12) used to transmit the data collected by the surface-mount thermistor (20) is not in contact with the voltage acquisition chip (30); The voltage acquisition chip (30) also includes: an extension claw (33); The PCB board (10) further includes: a fixing hole (11); the extension claw (33) extends into the fixing hole (11) to fix and encapsulate the voltage acquisition chip (30) on the PCB board (10).

2. The integrated temperature and pressure sensor according to claim 1, characterized in that, The window opening area (31) is a wraparound window or a three-sided enclosed window.

3. The integrated temperature and pressure sensor according to claim 1, characterized in that, The window area (31) is a three-sided enclosed window; The temperature acquisition circuit (12) includes positive and negative temperature acquisition solder joints (12a), positive and negative connecting lines (12b), and positive and negative temperature connection solder joints (12c). The positive and negative temperature acquisition solder joint (12a) is located within the window area (31); The positive and negative connecting lines (12b) extend from the window area (31); The positive and negative temperature connection solder joints (12c) are located outside the window area (31).

4. The integrated temperature and pressure sensor according to claim 3, characterized in that, The voltage acquisition chip (30) further includes a protrusion (32) located in the window area (31); the protrusion (32) bends upward relative to the extension plane of the voltage acquisition chip (30) and extends parallel to the extension plane of the voltage acquisition chip (30) toward the location of the surface mount thermistor (20); the protrusion (32) is used to protect the surface mount thermistor (20). The extension claw (33) bends downward relative to the extension plane of the voltage acquisition piece (30).

5. The integrated temperature and pressure sensor according to claim 3, characterized in that, The PCB board (10) is provided with a partition area (15), which is located between the positive and negative temperature connection solder joints (12c) and is used to physically isolate the positive and negative poles of the positive and negative temperature connection solder joints (12c); the extension length of the partition area (15) is equal to the extension length of the positive and negative temperature connection solder joints (12c).

6. The integrated temperature and pressure sensor according to claim 5, characterized in that, The integrated thermo-baric sensor (100) also includes: The first encapsulating adhesive (51) is disposed on the PCB board (10) for encapsulating the surface mount thermistor (20) within the window area (31); The second encapsulating adhesive (52) is disposed on the PCB board (10) and is used to encapsulate the positive and negative temperature connection solder joints (12c) and the pressure connection solder joints (13b) in the voltage acquisition circuit (13); The third encapsulating adhesive (53) is disposed on the PCB board (10) and is used to encapsulate other circuit structures exposed on the PCB board (10).

7. The integrated temperature and pressure sensor according to claim 3, characterized in that, The overall length of the PCB board (10) is L, the distance from the center of the positive and negative temperature connection solder joint (12c) to the first edge of the PCB board (10) is L1, and the distance from the center of the positive and negative temperature connection solder joint (12c) to the second edge of the PCB board (10) is L2. The first edge is the edge close to the external lead and satisfies: 12±0.3mm≤L≤16±0.3mm, and 3:7≤L1:L2≤5:

5.

8. A packaging method for a chip-shaped integrated temperature and pressure sensor, applied to the chip-shaped integrated temperature and pressure sensor as described in any one of claims 1-7, characterized in that, Includes the following steps: S1, a PCB board (10) is provided, the PCB board (10) is provided with a fixing hole (11), a temperature acquisition circuit (12) and a voltage acquisition circuit (13), the fixing hole (11) is located on the path of the voltage acquisition circuit (13), and the inner wall of the fixing hole (11) is covered with copper material; S2, a voltage acquisition chip (30) is provided, the voltage acquisition chip (30) having a window area (31) and an extension claw (33); S3, Solder paste is provided in the fixing hole (11), and the extension claw (33) is inserted into the fixing hole (11) to fix the voltage acquisition piece (30) to the front side of the PCB board (10) by soldering; S4, a surface mount thermistor (20) is provided and the surface mount thermistor (20) is placed in the window area (31) and electrically connected to the temperature acquisition circuit (12); S5, the voltage acquisition chip (30) and the surface mount thermistor (20) are encapsulated on the PCB board (10) using encapsulating adhesive.

9. The packaging method for the integrated temperature and pressure sensor according to claim 8, characterized in that, The process following step S2 also includes: The extension claw (33) and protrusion (32) of the voltage acquisition piece (30) are pre-formed, so that the extension claw (33) bends downward relative to the extension plane of the voltage acquisition piece (30), and the protrusion (32) bends upward relative to the extension plane of the voltage acquisition piece (30) and extends along the extension plane of the voltage acquisition piece (30) to the location of the surface mount thermistor (20).

10. The packaging method for the integrated temperature and pressure sensor according to claim 8, characterized in that, Step S5 specifically includes: S51, apply the first encapsulating adhesive (51) to encapsulate the surface mount thermistor (20) within the window area (31); S52, apply a second encapsulating adhesive (52) to encapsulate the positive and negative temperature connection solder joints (12c) in the temperature acquisition circuit (12) and the pressure connection solder joints (13b) in the voltage acquisition circuit (13); S53, apply a third encapsulating adhesive (53) to encapsulate other circuit structures exposed on the PCB board (10).

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