CN200990508Y - Overcurrent and overvoltage protection integrated block device - Google Patents

Abstract

The over-current and over-voltage protection integrated circuit device of the present invention includes an over-current protection (OCP) device and an over-voltage protection (OVP) device. One end of the OCP element is electrically connected with a first contact, and the other end of the OCP element is electrically connected with a second contact. One end of the OVP element is electrically connected with a third joint, the other end of the OVP element is electrically connected with the second joint, and the second joint is a common joint. The OCP element and the OVP element are modularly integrated into an integrated block form, the first, the second and the third contacts are externally connected with a circuit to be protected, so that the OCP element is connected in series with the circuit to be protected, and the OVP element is connected in parallel with the circuit to be protected.

Description

Overcurrent and overvoltage protection integrated block device

technical field

The utility model relates to an over-current and over-temperature protection device, in particular to a modular over-current and over-voltage protection integrated block device.

Background technique

Telecommunications systems have now become an integral part of human daily life, such as telephones, networks, and wireless communications, all of which transmit signals through telecommunication systems. Most of the telecommunication systems contain conductors such as metals for signal transmission, so it is often possible to be struck by lightning. In addition to the high current generated by lightning strikes, its high voltage is often the main cause of damage to telecommunication systems. Therefore, protection devices used in communication environments must have dual characteristics of over-current protection (Over-Current Protection; OCP) and over-voltage protection (Over-Voltage Protection; OVP).

The resistance value of a conventional positive temperature coefficient (Positive Temperature Coefficient; PTC) element responds quite sensitively to temperature changes. When the PTC element is in normal use, its resistance can maintain a very low value so that the circuit can operate normally. However, when the temperature rises to a critical temperature due to an over-current or over-temperature phenomenon, its resistance value will instantly jump to a high-resistance state (for example, above 10 ⁴ ohms), and the excessive current will be counteracted in reverse to achieve purpose of protecting batteries or circuit components.

Generally speaking, PTC components can be roughly divided into two types: polymer PTC (Polymeric PTC; PPTC) and ceramic (Ceramic PTC; CPTC). Both PPTC and CPTC have superior high current resistance characteristics, and are often used as OCP components.

In addition, varistors and gas discharge tubes are usually in a high-resistance state, but when an overvoltage occurs, they can be converted into a low-resistance state in an instant, and then grounded, so they can withstand high voltage And used as OVP element.

Therefore, the combination of OCP and OVP elements has become the main implementation aspect of protection devices currently used in communication equipment. Traditionally, OCP and OVP components are independent components, which must be connected by multiple hardware parts and covered with plastic parts for fixing and insulation protection. In addition, it can be connected with a light emitting diode (LED) in series, as an indication of signal output under abnormal conditions such as over-current or over-voltage. Although the protection device manufactured by this traditional method has a simple structure and low cost, its assembly is very labor-intensive and has a large volume after assembly, which is not suitable for the current miniaturized electronic devices.

In addition, the current overcurrent and overvoltage protection components are directly made into analog power ICs by using semiconductor technology. However, the manufacturing process is complicated and the cost is high, which is not conducive to being widely used in general consumer electronic products.

Contents of the invention

The utility model provides an overcurrent and overvoltage protection integrated block device, which integrates and modularizes the original independent OCP elements and OVP elements, has the advantages of high power resistance, simple manufacturing process, low cost and small volume, and is very convenient. use, while suitable for communication device applications.

The overcurrent and overvoltage protection integrated block device of the utility model includes an OCP element and an OVP element. One end of the OCP element is electrically connected to a first contact, and the other end is electrically connected to a second contact. One end of the OVP element is electrically connected to a third contact, and the other end is electrically connected to the second contact, and the second contact is a common point. The OCP element and the OVP element are modularly integrated into an integrated block form, and the first, second and third contacts are externally connected to the circuit to be protected, so that the OCP element is connected in series to the circuit to be protected, and the OVP The element is connected in parallel with the circuit to be protected.

Preferably, the OCP element and the OVP element can be formed in the integrated block in the form of a semiconductor package (such as TO-220 or TO-263). 1. Second and third contacts.

In addition, the OCP and OVP components can also be in the form of surface mount (SMD) or chip (chip), using bonding pads and wire bonding to connect the OCP components and OVP components to the contacts.

Compared with traditional ones, the overcurrent and overvoltage protection integrated block device of the utility model has the advantages of high power resistance, simple manufacturing process, low cost and small volume. Modularization of the OCP and OVP components can greatly save traditional assembly time and facilitate practical applications.

Description of drawings

Fig. 1 (a)～1 (c) is the circuit schematic diagram of the overcurrent and overvoltage protection integrated block device of the present utility model;

Fig. 2 and Fig. 3 exemplify the overcurrent and overvoltage protection integrated block device of the utility model utilizing package form; And

4 to 7(c) show overcurrent and overvoltage protection integrated block devices of other embodiments of the present invention.

Detailed ways

Referring to Fig. 1 (a), it is the circuit diagram of overcurrent and overvoltage protection device of the present utility model, and it comprises an OCP element 11 and-OVP element 12, and described OCP element 11 forms series connection with the circuit to be protected, and The OVP element 12 is connected in parallel with the circuit to be protected. The contacts are respectively denoted by A, B, and C, and the contact C is connected in parallel with the OCP element 11 and the OVP element 12, and is a common point.

The OCP element 11 can be a PPTC element 11 ′, and the OVP element 12 can be a Zener diode, as shown in FIG. 1( b ). In addition, the OCP element 11 can also be a fuse 11 ″, as shown in FIG. 1( c ).

Figures 2 and 3 show overcurrent and overvoltage protection devices fabricated using off-the-shelf packaging technology. The overcurrent and overvoltage protection device illustrated in FIG. 2 applies TO-220 standard semiconductor packaging technology. An OVP element 22 and -OCP element 24 are packaged in TO-220 mode, and are electrically connected to the common contact C, and are respectively connected to the welding pad 26 on the pin 21 with the welding wire 25, forming an overcurrent and overcurrent. Voltage protection device 20. As shown in FIG. 2, the contacts A, B, and C on the pin 21 correspond to the contacts A, B, and C of FIG. 1(a), so they can be used after proper connection.

FIG. 3 illustrates an overcurrent and overvoltage protection device according to a second embodiment of the present invention, which uses TO-263 semiconductor packaging technology. An OVP element 32 and an OCP element 34 are packaged in TO-263, and are electrically connected to the common contact point C, and are respectively connected to the welding pad 36 on the pin 31 with a welding wire 35 to form an overcurrent and Overvoltage protection device 30. As shown in FIG. 3 , the contacts A, B, and C on the pin 31 correspond to the contacts A, B, and C of FIG. 1( a ), so they can be used after proper connection.

Fig. 4 illustrates the overcurrent and overvoltage protection device made by the surface mount (SMD) technology of the present invention, which is a top view of an overcurrent and overvoltage protection device 40, and the electrodes are arranged on the left and right sides. The -OCP element 47 and -OVP element 48 are disposed on a substrate 41 , and one end is connected to the pad 42 , and the other end is connected to the pad 43 and 44 respectively. The substrate 41 can be a PCB board (glass fiber board), a ceramic board (such as an alumina board) or a plastic board. The welding pads 43 and 44 are electrically connected to the conductive vias on the left side through the conductive channel 45, corresponding to the positions A and B in FIG. The conductive via hole on the side corresponds to the contact point C in Figure 1(a). The conductive vias A, B and C may be in the form of full round holes or semicircular holes.

Referring to FIG. 5, it is a top view of an overcurrent and overvoltage protection device 50, which is in the form of a chip, that is, the electrodes are arranged on the upper and lower sides. An OCP element 57 and an OVP element 58 are disposed on the bonding pad 52 on the surface of a substrate 51 and connected to the bonding pad 53 through the bonding wire 54 . The pads 53 are electrically connected to the conductive vias on the left by the conductive channels 55 , corresponding to the contacts A and B in FIG. 1( a ). The pad 52 is connected to the conductive via hole on the right through the conductive channel 56 , which corresponds to the contact point C in FIG. 1( a ). The conductive vias A, B and C may be in the form of full round holes or semicircular holes.

Referring to Fig. 6 (a) ~ 6 (c), it shows the overcurrent and overvoltage protection integrated block device 60 of another embodiment, wherein Fig. 6 (b) is the top view of Fig. 6 (a), Fig. 6 (c ) is a schematic circuit diagram of the overcurrent and overvoltage protection integrated block device 60. The upper and lower sides of an OVP element 62 (such as a piezoresistor MOV) are respectively connected to the left and right electrodes 66 and 67 through the conductive layer 63 to form a conductive path connecting the OVP element 62 in series at points B and C. A conductive via 64 runs through the OVP element 62 , and is surrounded by an insulating layer 65 to be electrically insulated from the OVP element 62 . An OCP element (such as a PPTC element) 61 is connected across the left electrode 66 and an intermediate electrode 68 above the conductive via 64 to form a series connection of the OCP element 61 at points A and C. Conductive pathway. In this way, the OVP element 62 and the OCP element 61 are connected in parallel, and point C is a common point.

Referring to Fig. 7 (a) ~ 7 (c), it shows the overcurrent and overvoltage protection integrated block device 70 of another embodiment, wherein Fig. 7 (b) is the top view of Fig. 7 (a), Fig. 7 (c ) is a schematic circuit diagram of the overcurrent and overvoltage protection integrated block device 70. - The upper and lower sides of the OCP element 72 (such as a PPTC element) are respectively connected to the left and right electrodes 76 and 77 through the conductive layer 73 to form a conductive path connecting the OCP element 72 in series between points A and C. A conductive via 74 runs through the OCP element 72 , and is surrounded by an insulating layer 75 to be electrically isolated from the OCP element 72 . An OVP element (such as a varistor MOV or Zener diode) 71 is connected across the left electrode 76 and an intermediate electrode 78 above the conductive via 74 to form a series connection of the OVP element 71 Conductive paths at points B and C. In this way, the OCP element 72 and the OVP element 71 are connected in parallel, and the point C is its common point. Surfaces of the insulating layer 75 located on the upper and lower sides of the OCP element 72 are respectively covered with a solder mask (solder mask) 79 .

Table 1 shows the performance comparison between the overcurrent and overvoltage protection integrated block device of the present invention and conventional ones.

Table I

Features The utility model   Analog IC form   Combining OCP and OVP components   Primary or Secondary Protection Primary/Secondary Primary/Secondary Secondary   Endurance power high Low high Reaction time quick quick Medium Process Simple complex Simple cost Cheap expensive Medium Component size Small Small big

It can be seen from Table 1 that the overcurrent and overvoltage protection integrated block device of the present invention has the advantages of high power resistance, fast response time, simple manufacturing process, low cost and small size compared with the traditional one, and is very suitable for application in communication devices .

The technical content and technical features of the present utility model have been disclosed above, but those skilled in the art may still make various replacements and modifications based on the teaching and disclosure of the present utility model without departing from the spirit of the present utility model. Therefore, the protection scope of the utility model should not be limited to the contents disclosed in the embodiments, but should include various replacements and modifications that do not depart from the utility model, and are covered by the appended claims.

Claims (15)

1. overcurrent and overvoltage protection integrated package device is characterized in that comprising:

One overcurrent protection (OCP) element, the one end is electrically connected one first contact, and the other end is electrically connected one second contact; And

One overvoltage protection (OVP) element, the one end is electrically connected one the 3rd contact, and the other end is electrically connected described second contact, and described second contact is the common point of described OCP element and OVP element;

Wherein said OCP element and OVP element are that modularization is integrated into an integrated package form, and the external circuit to be protected of described first, second and third contact make described OCP element connected in series in circuit to be protected, and described OVP element is parallel to circuit to be protected.

2. overcurrent as claimed in claim 1 and overvoltage protection integrated package device is characterized in that described OCP element and OVP element are to produce described integrated package form with packing forms.

3. overcurrent as claimed in claim 2 and overvoltage protection integrated package device is characterized in that comprising in addition three pins, respectively as described first, second and third contact.

4. overcurrent as claimed in claim 3 and overvoltage protection integrated package device is characterized in that described OCP element and OVP element connect in described three pins two pins as the first and the 3rd contact with bonding wire respectively.

5. overcurrent as claimed in claim 1 and overvoltage protection integrated package device is characterized in that it being surface adhering (SMD) form.

6. overcurrent as claimed in claim 1 and overvoltage protection integrated package device is characterized in that described OCP and OVP protection component are by a substrate supporting.

7. overcurrent as claimed in claim 6 and overvoltage protection integrated package device is characterized in that described substrate is a glass mat, a ceramic wafer or a plastic plate.

8. overcurrent as claimed in claim 1 and overvoltage protection integrated package device; it is characterized in that described OCP element one end is connected in one first weld pad; described OVP element one end is connected in one second weld pad; the other end of described OCP element and described OVP element is common to connect one the 3rd weld pad, and described first, second and third weld pad is electrically connected described first, the 3rd and second contact respectively.

9. overcurrent as claimed in claim 1 and overvoltage protection integrated package device; it is characterized in that described OCP element and described OVP element utilize bonding wire to connect one first weld pad and one second weld pad respectively; and described OCP element and described OVP element are arranged at one the 3rd weld pad surface jointly, and described first, second and third weld pad is electrically connected described first, the 3rd and second contact respectively.

10. overcurrent and overvoltage protection integrated package device as claimed in claim 8 or 9 is characterized in that described first, second and third contact is circular or semicircular conductive through hole.

11. overcurrent as claimed in claim 1 and overvoltage protection integrated package device; the upper and lower side that it is characterized in that described OVP element connects the left and right side electrode by conductive layer separately; run through a conductive through hole in the OVP element; coat an insulating barrier around the described conductive through hole and with described OVP element electric insulation, the cross-over connection of described OCP element is positioned at the target of described conductive through hole top in described left electrodes and.

12. overcurrent as claimed in claim 1 and overvoltage protection integrated package device; the upper and lower side that it is characterized in that described OCP element connects the left and right side electrode by conductive layer separately; run through a conductive through hole in the OCP element; coat an insulating barrier around the described conductive through hole and with described OCP element electric insulation, the cross-over connection of described OVP element is positioned at the target of described conductive through hole top in described left electrodes and.

13. overcurrent as claimed in claim 12 and overvoltage protection integrated package device is characterized in that described insulating barrier is positioned at described OCP element and is covered with solder mask in the surface of both sides up and down.

14. overcurrent as claimed in claim 1 and overvoltage protection integrated package device is characterized in that described OCP element adopts the high molecular positive temperature coefficient element.

15. overcurrent as claimed in claim 1 and overvoltage protection integrated package device is characterized in that described OVP element is Zener diode or piezo-resistance.

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