Lead frame structure capable of realizing flexible packaging of multifunctional chip of electronic cigarette sensor

Abstract

A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor comprises a packaging support, an upper cover, a lower cover, a protective net, a micro-electro-mechanical sensor and an ASIC chip, and adopts a device-level packaging technology which is a packaging support + main chip + outer cover mode; according to the electronic cigarette packaging structure, multifunctional output can be achieved, the number is increased according to the requirements of customers, pins can be flexibly used, and with the diversification of the requirements of electronic cigarettes, chips except an ASIC (Application Specific Integrated Circuit), such as an MCU chip, an OVP charging protection chip and a charging chip, can be mounted in a packaging cavity; due to the fact that the packaging support of the structure has the advantages that the number of the bonding pads is large, the internal chip is flexibly mounted, and the like, the electronic cigarette sensor can reflect the characteristics of diversification and intellectualization in design, and the electronic cigarette sensor conforms to the development of the future trend of electronic cigarettes.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic cigarette sensors, in particular to a lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor. Background Art

[0002] An electronic cigarette sensor is a device driven by a battery + an internal ASIC chip. It can convert the e-liquid into smoke through a heating wire, so that smokers can feel the smoke being inhaled. With the continuous development of technology and people's increasing attention to health, electronic cigarette sensors will become more and more popular, and their prospects are also very broad.

[0003] First, the use of electronic cigarette sensors is becoming more and more widespread. This has led to the continuous expansion of the electronic cigarette sensor market, and it will continue to grow in the future. Secondly, with the development of technology, the performance of electronic cigarette sensors is also constantly improving. In the current electronic cigarette market, electronic cigarette sensors will be more intelligent and diversified, and can better meet the needs of smokers. For example, some companies are developing electronic cigarette sensors with Bluetooth connection functions. Smokers can use them to track health data or receive instructions from smartphones to customize steam quality. Electronic cigarettes have wireless charging, location positioning, fingerprint identity authentication, screen display and other functional requirements, pushing the electronic cigarette industry into a more intelligent and diversified development field.

[0004] The existing electronic cigarette sensors on the market are all electret structures. The electret electronic cigarette sensor is essentially an airflow sensor and an integrated airflow sensor solution, including a micro-electromechanical sensor and a corresponding ASIC control chip. Its structure includes a dust net, a shell, a plate, a gasket, a cavity, a diaphragm and a copper ring, an ASIC, a capacitor, a circuit board, and an LED indicator. From this structure, it can be seen that the structure of the electret electronic cigarette sensor on the market is complex. The pressure sensor with a "hamburger" structure is mainly divided into two parts: a shell + a PCBA circuit board. The shell components include: a waterproof net, a shell, a substrate, a gasket, a cavity, a diaphragm and copper ring components; multiple parts The components are assembled into the shell part; the components of the PCBA circuit board include: LED indicator lights, capacitors, ASIC chip components, which can all be mounted by SMT patching; the two parts are fixed into an electret electronic cigarette sensor by riveting the aluminum-magnesium alloy shell. The ASIC pin definition of the SOT / DNF packaging mode includes the switch pin SW, the negative pole of the power supply (GND), the lamp pin (LED), the input and output pin (I / O), and the positive pole of the battery (VDD). The switch pin SW: airflow switch sensing pin, the negative pole of the power supply (GND): connected to the negative pole of the battery; the lamp pin (LED): output high voltage external LED; input and output pin (I / O): 3.6V PWM constant voltage output when working, power input pin when charging; power positive pole (VDD): connected to the positive pole of the battery; traditional electret electronic cigarette sensors have fewer pins, and more functions need to be realized by external MCU modules, and cannot realize other more diversified functional outputs, which cannot meet the needs of existing clients for more diversified functional outputs and cannot meet market needs.

[0005] The above structure also has the following disadvantages:

[0006] 1. The traditional electret structure is complex and the assembly process is complicated;

[0007] 2. The electret has few functional pads, which cannot be flexibly packaged and defined, and has weak variability, which cannot meet the needs of existing clients for more diversified functional outputs, such as key unlocking, internal OVP fuse protection for charging modules, etc.

[0008] 3. The internal impedance of the electret is relatively large, which affects the transmission of capacitance and electrical signals;

[0009] 4. The internal structure is compact, and the internal space of the electret is compact, so too many other functional chips cannot be placed;

[0010] 5. The ASIC chip in SOT / DNF package has few functional pins and limited functional output, which is not suitable for diversified functional output;

[0011] 6. More functional outputs need to be realized with an external MCU module, which greatly increases the cost of e-cigarettes because of the need to add MCU, MOS tube, charging management chip, and other peripheral circuits. Utility Model Content

[0012] 1. Technical issues to be solved

[0013] The main purpose of the utility model is to provide a lead frame structure that can realize flexible packaging of a multifunctional chip of an electronic cigarette sensor, which can effectively solve the problems in the background technology.

[0014] (II) Technical solution

[0015] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor, comprising a packaging bracket, an upper cover, a lower cover, a protective net, a micro-electromechanical sensor and an ASIC chip, wherein the packaging bracket is provided with a cavity with an upper opening, a high step is provided on one side of the bottom wall of the cavity, an air guide channel penetrating the high step and the bottom wall of the packaging bracket is provided on the high step, the micro-electromechanical sensor is also provided on the high step, a low step is provided in the cavity away from the high step, the ASIC chip is fixed on the low step, an upper cover adapted to the cavity is provided above the packaging bracket, the upper cover is provided with an air intake hole, a lower cover adapted to the air guide channel is provided below the packaging bracket, the lower cover is provided with an air inlet hole, a protective net is provided on the upper cover and the lower cover, the micro-electromechanical sensor is a capacitive sensor, a built-in LED lamp is also provided in the cavity, an external LED lamp is embedded below the packaging bracket, and the external LED lamp is connected to the built-in LED lamp and the ASIC chip.

[0016] In order to ensure consistency and strength, the utility model has the following improvements: the package bracket forms a large number of epitaxial pads, which can be packaged and used flexibly.

[0017] The utility model is improved in that a plurality of multifunctional chips can be flexibly mounted in the cavity of the packaging bracket.

[0018] The utility model has the following improvements: the bottom pad of the package bracket includes an epitaxial pad and an internally generated pad; the epitaxial pad can be used to weld external wires and can also be used to mount chips.

[0019] The invention has the advantage that the width of the external wiring pad that can be welded is greater than 0.6 mm.

[0020] The novel improvement of the present invention is that the micro-electromechanical sensor and the ASIC chip are respectively fixed at the high step and the low step in the packaging cavity by means of a fixing colloid.

[0021] The novel improvement of the present invention is that the micro-electromechanical sensor, the ASIC chip and the packaging bracket are connected by using a bonding wire circuit.

[0022] The invention has the advantages that the ASIC chip and the surrounding gold wires are sealed with heat-conducting encapsulating glue.

[0023] (III) Beneficial effects

[0024] Compared with the prior art, the utility model provides a lead frame structure that can achieve flexible packaging of the multifunctional chip of the electronic cigarette sensor, which has the following beneficial effects:

[0025] 1. Compared with the traditional electret structure, the packaging structure is simpler and has fewer assembly steps;

[0026] 2. As functions increase according to customer needs, the number of pins also continues to rise. With the diversification of e-cigarette needs, the ASIC chip in the package cavity can meet multi-function output and meet the needs of existing clients for more diversified function output, such as key unlocking, screen, positioning, built-in MCU module and other functions;

[0027] 3. Compared with electret, the internal impedance of this structure is small, and the bottom of ASIC and the bottom of the package bracket are connected by metal, resulting in strong heat dissipation performance, improved power output, and solving the difficulty of low power of traditional packaging;

[0028] 4. The internal structure of the package cavity is spacious and has a large number of pads. The package cavity can be mounted with chips other than ASIC, and can also be mounted with other chips such as MCU, OVP charging protection chip, charging chip, with many functional pads, which can be flexibly packaged and defined, and can hold multiple multifunctional chips, and the pads can be flexibly defined;

[0029] 5. Compared with the electret sensor, this flexible packaging mode allows the ASIC itself to achieve multi-functional output, which can reduce the additional costs brought by the MCU, MOS tube, charging management chip, and other peripheral circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the cross section of the structure of the utility model;

[0031] Figure 2 This is a bottom view schematic diagram of the external wiring of the utility model structure;

[0032] Figure 3 This is a top view of the utility model structure with the upper cover opened;

[0033] Figure 4 It is a side view schematic diagram of the structure of the utility model;

[0034] Figure 5 This is a top view schematic diagram of the external wiring of the structure of the utility model;

[0035] Figure 6 This is a top view schematic diagram of the external wiring using a new structure.

[0036] In the figure: 1. Packaging bracket; 2. Upper cover; 3. Lower cover; 4. MEMS sensor; 5. ASIC chip; 6. Protective net; 7. Bonding wire; 8. Thermal encapsulation glue; 9. High step; 10. Low step; 11. Built-in LED light; 12. External LED light; 13. Solder pad; 14. Air intake hole; 15. Air intake hole. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0038] See also Figure 1-6 A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor, comprising a packaging bracket 1, an upper cover 2, a lower cover 3, a protective net 6, a micro-electromechanical sensor 4 and an ASIC chip 5. The packaging bracket 1 is provided with a cavity with an upper opening, a high step 9 is provided on one side of the bottom wall of the cavity, an air guide channel penetrating the high step 9 and the bottom wall of the packaging bracket 1 is provided on the high step 9, the micro-electromechanical sensor 4 is also provided on the high step 9, a low step 10 is provided in the cavity away from the high step 9, and the ASIC chip 5 is fixed on the low step An upper cover 2 adapted to the cavity is arranged above the packaging bracket 1, and the upper cover 2 is provided with an air intake hole 14, and a lower cover 3 adapted to the air guide channel is arranged below the packaging bracket 1, and the lower cover 3 is provided with an air inlet hole 15, and a protective net 6 is arranged on the upper cover 2 and the lower cover 3, the micro-electromechanical sensor is a capacitive sensor, and a built-in LED lamp 11 is also arranged in the cavity, and an external LED lamp 12 is embedded below the packaging bracket 1, and the external LED lamp 12 is connected to the built-in LED lamp 11 and the ASIC chip 5.

[0039] The silicon-based chips in the present invention, such as micro-electromechanical sensors and ASIC chips 5, all adopt MEMS device-level packaging technology. MEMS packaged sensors have the characteristics of small size, light weight, low cost, low power consumption, high reliability, suitable for mass production, easy integration and intelligent realization.

[0040] The MEMS sensor of electronic cigarette is a capacitive sensor, and its working principle is as follows: one diaphragm pole of the capacitor can sense the change of air pressure and play the role of air pressure signal intake. In the MEMS sensor, this pole is composed of a diaphragm with silicon crystal as the pad, and forms a variable capacitor space with changeable inter-pole distance with the other pole. When there is air pressure, the diaphragm is deformed, and the deformation size is determined by the inhalation pressure when smoking. When the capacitance reaches a certain value, the ASIC receives the capacitance change signal, and thus works normally, starts the heating wire, and starts the LED lighting effect. Its basic working principle is as described above.

[0041] The lead frame structure adopts device-level packaging technology, which is a packaging bracket + main chip + outer cover mode;

[0042] Package bracket: The metal is formed by stamping to form the basic frame of the bracket, and then processed by a stretching process to form the metal frame structure of the package bracket. An electrolyte is used on the metal surface to coat the surface with a layer of metal that protects the raw material metal of the bracket and a weldable coating. The coating can be a weldable protective layer such as gold, silver, nickel-palladium-gold, OSP, etc. In this design, the bottom pads of the package bracket include 9 epitaxial pads and 2 internal generated pads. Among the 9 epitaxial pads, 8 can be used as pads for welding external wires. Except for the second pad, the minimum width of the weldable external wire pad must be above 0.6mm.

[0043] Main chip: MEMS sensor + ASIC solution. The MEMS sensor is fixed to the high step on the right side of the package bracket using colloid. The ASIC chip is in contact with the metal pad at the bottom of the package bracket using thermal conductive glue. The circuits between the MEMS and ASIC chips are connected using bonding wires. The circuits between the ASIC chip and the pads are connected using bonding wires.

[0044] Outer cover: The outer cover includes an upper cover and a lower cover. The upper cover is provided with air guide holes and a protective net coated with a nano-film is attached inside. It is attached to the top of the packaging bracket with colloid. The lower cover is provided with air guide holes and a protective net coated with a nano-film is attached inside. It is attached to the bottom of the packaging bracket with colloid.

[0045] Compared with the traditional SOT / DFN packaged ASIC, this design of ASIC chip features more pins, the pin definitions include button pin (SEN), battery input pin (BAT), LED lighting effect pin (LED), charging pin (CHG), output I / 0 pin (AT), power negative pole (GND), burning pin (TEST), etc., which can realize multi-function output. According to the increase in customer requirements, the number of pins is also increasing. With the diversification of electronic cigarette demand, chips other than ASIC can be mounted in the packaging cavity, such as circuit reverse protection chip, OVP charging protection chip, charging chip, circuit reverse protection chip: chip with battery positive and negative pole reverse protection, input power positive and negative pole reverse protection; OVP charging protection chip: OV P is usually implemented using components such as protection diodes or voltage regulators. When the input voltage exceeds the set threshold, the protection diode or voltage regulator will shunt or consume the excessive voltage to protect the circuit from overvoltage; Charging chip: a chip that enables an ASIC that was originally non-chargeable to have a charging function, that is, an ASIC that originally packaged a disposable electronic cigarette, which had no charging function and now needs to be charged multiple times. Using this packaging mode, a charging chip is mounted in the cavity of the packaging bracket, so that the electronic cigarette sensor can be charged multiple times; due to the characteristics of the packaging bracket of this structure: a large number of pads, flexible internal mounting settings, etc., the electronic cigarette sensor can be designed to reflect the characteristics of diversity and intelligence, which is in line with the future development trend of electronic cigarettes.

[0046] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0047] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0048] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0049] Although the embodiments of the utility model have been shown and described, it is understood that a person of ordinary skill in the art can make various changes, modifications, substitutions and variations to these embodiments without departing from the principle and spirit of the utility model. The scope of the utility model is limited by the attached claims and their equivalents. The above embodiments only express several preferred implementations of the utility model, and the description is more specific and detailed. It should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as an exclusion of other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept of this article through the above teachings or the technology or knowledge of the relevant field, and it cannot be understood as a limitation on the scope of the utility model. It should be pointed out that a person of ordinary skill in the art can make several deformations and improvements without departing from the concept of the utility model. The changes and modifications made by the personnel in the field do not depart from the spirit and scope of the utility model, and these belong to the scope of protection of the attached claims of the utility model. Therefore, the scope of protection of the utility model patent shall be subject to the attached claims.

Claims

1. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor, characterized in that: The invention comprises a packaging support (1), an upper cover (2), a lower cover (3), a protective net (6), a micro-electromechanical sensor (4) and an ASIC chip (5); the packaging support (1) is provided with a cavity with an upper opening; a high step (9) is provided on one side of the bottom wall of the cavity; an air guide channel penetrating the high step (9) and the bottom wall of the packaging support (1) is provided on the high step (9); the micro-electromechanical sensor (4) is also provided on the high step (9); a low step (10) is provided in the cavity away from the high step (9); the ASIC chip (5) is fixed on the low step; a sealing member (10) is provided above the packaging support (1); An upper cover (2) adapted to the cavity is provided, the upper cover (2) is provided with an air intake hole (14), a lower cover (3) adapted to the air guide channel is provided below the packaging bracket (1), the lower cover (3) is provided with an air intake hole (15), a protective net (6) is provided on the upper cover (2) and the lower cover (3), the micro-electromechanical sensor (4) is a capacitive sensor, a built-in LED lamp (11) is also provided in the cavity, an external LED lamp (12) is embedded below the packaging bracket (1), and the external LED lamp (12) is connected to the built-in LED lamp and the ASIC chip (5).

2. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: The packaging bracket (1) has a large number of epitaxial pads, which can be packaged and used flexibly.

3. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: A plurality of multifunctional chips can be flexibly mounted in the cavity of the packaging bracket (1).

4. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: The bottom solder pad of the packaging bracket (1) comprises an epitaxial solder pad and an internally generated solder pad, and the epitaxial solder pad can be used to solder external wires or patches.

5. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 4, characterized in that: The width of the epitaxial pad is greater than 0.6 mm.

6. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: The micro-electromechanical sensor (4) and the ASIC chip (5) are respectively fixed at the high step (9) and the low step (10) in the packaging cavity by means of a fixing colloid.

7. A lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: The micro-electromechanical sensor (4), the ASIC chip (5), and the packaging bracket (1) are connected by using a bonding wire (7) circuit.

8. The lead frame structure capable of realizing flexible packaging of a multifunctional chip of an electronic cigarette sensor according to claim 1, characterized in that: The ASIC chip (5) and the surrounding bonding wires are sealed with a heat-conducting encapsulating adhesive (8).

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