Novel surface-mounted temperature sensor

Abstract

The utility model discloses a novel surface-mounted temperature sensor. Comprising a thermistor and further comprises a plastic package body, a frame base island and four frame pins located on the two sides of the frame base island are arranged in the plastic package body, and the frame pins on the two sides extend out of the edges of the two sides of the plastic package body respectively; the thermistor is located in the plastic package body and comprises thermal sensitive ceramic, metal electrodes are arranged at the top and the bottom of the thermal sensitive ceramic respectively, the metal electrode at the top of the thermistor is connected with the frame pins on the two sides through two wires respectively, and the metal electrode at the bottom of the thermistor is connected with the base island plane at the top of the frame base island. And the base island plane is respectively connected with the other frame pins on the two sides through two wires. The temperature sensor has the advantages of strong vibration resistance, long-term reliability and sensitive temperature sensing.

Description

Technical Field

[0001] The utility model relates to a thermistor element, in particular to a novel patch type temperature sensor. Background Art

[0002] Temperature sensors are widely used, and their resistance value changes significantly with temperature, so the temperature can be detected by detecting the resistor. However, existing SMD temperature sensors have the following problems: 1. The SMD resistor is not firmly bonded to the printed circuit board; 2. There is only a very thin protective film on the outside, which has poor ability to prevent mechanical damage; 3. The temperature fluctuates greatly and the measurement accuracy is poor. Utility Model Content

[0003] In view of the above problems, the utility model provides a novel patch type temperature sensor.

[0004] The technical solution of the utility model is: a novel chip temperature sensor, including a thermistor and a plastic package, wherein the plastic package is provided with a frame base island and four frame pins located on both sides of the frame base island, and the frame pins on both sides extend out of the edges of both sides of the plastic package respectively;

[0005] The thermistor is located in the plastic package and includes a thermistor ceramic, and the top and bottom of the thermistor ceramic are respectively provided with metal electrodes.

[0006] The top metal electrode of the thermistor is connected to one frame pin on each side through two wires, and the bottom metal electrode is connected to the base island plane at the top of the frame base island, and the base island plane is connected to the remaining frame pins on both sides through two wires.

[0007] It also includes an aluminum plate, through which the bottom metal electrode of the thermistor is connected to the base island plane, and the aluminum plate on the base island plane is respectively connected to the remaining frame pins on both sides through two wires.

[0008] The surface of the thermistor is provided with colloid.

[0009] The bottom of the frame base island exposes the plastic package.

[0010] Connecting ribs are respectively arranged at two ends of the frame base island, and the connecting ribs extend out of the plastic packaging body.

[0011] A base island silver-plated area is provided on the base island plane.

[0012] The frame pins are provided with glue locking holes.

[0013] The frame pins are provided with pin silver-plated areas.

[0014] In operation, the utility model places the chip thermistor on the frame and uses plastic packaging to make it. There are 8 frame pins on both sides, and the bonding force with the printed circuit board is greatly enhanced, which can be suitable for application scenarios with long-term vibration. The frame base island directly contacts the printed circuit board, and the thermistor can quickly reach the specified temperature through heat conduction. The outside is protected by the plastic package, which has a strong ability to prevent mechanical damage, and the plastic package has poor thermal conductivity, which prevents the temperature of the thermistor from being disturbed by the air flow above, and has high measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0016] Figure 2 This is a schematic diagram of the back structure of the utility model;

[0017] Figure 3 This is a cross-sectional schematic diagram of the thermistor of the utility model;

[0018] Figure 4 This is a schematic diagram of the framework structure of the utility model;

[0019] Figure 5 This is a schematic diagram of the back structure of the frame of the utility model;

[0020] Figure 6 This is a schematic diagram of the internal structure of Embodiment 1 of the present utility model;

[0021] Figure 7 This is a schematic diagram of the internal structure of Embodiment 2 of the present utility model;

[0022] Figure 8 This is a partial structural diagram of Embodiment 3 of the present utility model;

[0023] In the figure: 1, plastic sealing body; 101, plastic sealing body bevel; 102, plastic sealing body top glue hole;

[0024] 2. Thermistor; 201. Thermistor ceramic; 202. Metal electrode;

[0025] 3. Frame base island; 301. Base island plane; 302. Connecting ribs; 303. Indentation; 304. Base island silver-plated area; 305. Edge pressing; 306. Anti-overflow groove;

[0026] 4. Frame pin; 401. Glue lock hole; 402. Pin silver-plated area;

[0027] 5. Wire; 501. One soldering point; 502. Two soldering points; 6. Aluminum plate; 7. Colloid. DETAILED DESCRIPTION

[0028] The utility model Figure 1-5As shown, the novel surface mount temperature sensor includes a plastic package 1, a thermistor 2, a frame base island 3, a frame pin 4, a wire 5, an aluminum plate 6, and a colloid 7.

[0029] The frame base island 3 and the frame pin 4 are formed by cutting off the same frame as a whole. The frame is made of copper alloy, for example.

[0030] The plastic package is exposed at the bottom of the frame base island 3. The connecting rib 302 connects the frame base island to the outside. The indentation 303 is located near the connecting rib 302 on the base island plane 301, which is used to enhance the bonding force between the frame and the plastic package to prevent the connecting rib 302 from affecting the inside when it is cut off from the overall frame. The base island silver-plated area 304 is located on the base island plane 301 to ensure that a welding point 501 of the wire 5 is well bonded to the base island plane 301. There is a pressing edge 305 (a pressing edge groove is formed by extrusion) on the back of the base island plane 301, which is used to enhance the bonding force between the base island plane 301 and the plastic package 1, thereby enhancing product reliability.

[0031] The glue locking hole 401 is located on the frame pin 4 to enhance the bonding force between the frame pin and the plastic package 1 and prevent the pin from being pulled off the plastic package during the molding process. The pin silver-plated area 402 is located on the frame pin 4 to ensure that the two solder joints 502 of the wire 5 are well bonded to the frame pin 4.

[0032] The thermistor 2 includes a thermistor ceramic 201 and a metal electrode 202. The thermistor ceramic is made of a mixture of multiple metal oxides and has a negative temperature characteristic. The metal electrode 202 is at the top and bottom of the thermistor ceramic 201 and is used to connect to the outside to reduce the contact resistance. The wire 5 is used to connect the thermistor 2 to the frame pin 4 and is led to the outside through the pin 4.

[0033] like Figure 6 As shown, in Example 1, the thermistor 2 is fixed to the base island plane 301 by conductive glue, two wires 5 connect the top metal electrode 202 of the thermistor 2 to the pin, and two wires 5 connect the bottom metal electrode 202 of the thermistor 2 to the pin through the base island plane 301.

[0034] like Figure 7 As shown, in Example 2, the aluminum plate 6 is fixed to the base island plane 301 by insulating glue, the thermistor 2 is fixed to the aluminum plate 6 by conductive glue, two wires 5 connect the top metal electrode 202 of the thermistor 2 to the pin, and two wires 5 connect the bottom metal electrode 202 of the thermistor 2 to the pin through the aluminum plate 6. The aluminum plate is used because it has good conductivity.

[0035] At the same time, a layer of aluminum plate is added in the middle to connect the base island through insulating glue, so as to provide insulation to prevent the influence on other devices in the circuit and the influence of other devices on the thermistor.

[0036] like Figure 8As shown, in Example 3, based on Example 1 or 2, a layer of jelly-like colloid 7 is covered on the surface of the thermistor 2 to wrap and protect the solder joints of the thermistor 2 and the wire 5 to prevent them from being damaged and failing under temperature shock. The colloid is, for example, polydimethylsiloxane adhesive, or other colloids that can protect the thermistor, have good fluidity and can be cured.

[0037] The plastic package body 1 encapsulates and protects all other parts. The bottom of the frame base island is exposed for connecting the printed circuit board, and the heat of the circuit board is quickly transferred to the thermistor 2. The anti-overflow groove 306 is located at the bottom of the frame base island to prevent the plastic package body 1 from overflowing and covering the bottom during the plastic packaging process. The exposed surface of the plastic package body 1 is electroplated with tin for welding. The frame pin 4 has the shape of a seagull foot and has a good bonding force with the printed circuit board. The plastic package body bevel 101 and the plastic package body top glue hole 102 are used to facilitate the plastic package body 1 to be separated from the mold after curing. The plastic package body top glue hole 102 can also be printed on the plastic package body to facilitate product traceability.

[0038] Regarding the contents disclosed in this case, there are a few points that need to be explained:

[0039] (1) The drawings of the embodiments disclosed in this case only involve the structures involved in the embodiments disclosed in this case. Other structures can refer to the general design;

[0040] (2) In the absence of conflict, the embodiments and features of the embodiments disclosed in this case may be combined with each other to obtain new embodiments;

[0041] The above are only specific implementation methods disclosed in this case, but the protection scope of the present disclosure is not limited thereto. The protection scope disclosed in this case should be based on the protection scope of the claims.

Claims

1. A novel chip temperature sensor, including a thermistor, characterized in that: It also includes a plastic package body, wherein a frame base island and four frame pins located on both sides of the frame base island are provided in the plastic package body, and the frame pins on both sides extend out of the edges of both sides of the plastic package body respectively; The thermistor is located in the plastic package and includes a thermistor ceramic, and the top and bottom of the thermistor ceramic are respectively provided with metal electrodes. The top metal electrode of the thermistor is connected to one frame pin on each side through two wires, and the bottom metal electrode is connected to the base island plane at the top of the frame base island, and the base island plane is connected to the remaining frame pins on both sides through two wires.

2. The novel patch temperature sensor according to claim 1 is characterized in that: It also includes an aluminum plate, through which the bottom metal electrode of the thermistor is connected to the base island plane, and the aluminum plate on the base island plane is respectively connected to the remaining frame pins on both sides through two wires.

3. The novel patch temperature sensor according to claim 1 or 2, characterized in that: The surface of the thermistor is provided with colloid.

4. The novel patch temperature sensor according to claim 1 is characterized in that: The bottom of the frame base island exposes the plastic package; Connecting ribs are respectively arranged at two ends of the frame base island, and the connecting ribs extend out of the plastic packaging body.

5. The novel patch temperature sensor according to claim 1 is characterized in that: A base island silver-plated area is provided on the base island plane.

6. The novel patch temperature sensor according to claim 1 is characterized in that: The frame pins are provided with glue locking holes.

7. The novel patch temperature sensor according to claim 1 is characterized in that: The frame pins are provided with pin silver-plated areas.

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