TWI514433B - Surface mount fuse and a structure with surface mount fuse - Google Patents

Description

Surface with a fuse and a structure with a surface attached to the fuse

The present invention relates to a surface-attached fuse and a structure having a surface-attached fuse, and particularly relates to a fuse of high durability, because a non-conductive member composed of a ceramic material having high mechanical strength and a ceramic tube are used, and the ceramic tube is used. The ceramic tube can be stably used at a high voltage by bonding the welding ring to the sealing electrode and improving the time delay characteristics and the production method.

Fuses are typically placed in electronic devices such as televisions, computers, card radios, small electronic devices, and similar electronic devices. When an overvoltage is applied to it, the fuse will melt and block the power transfer, preventing the circuit and electronic components from being damaged by overvoltage.

Under normal conditions, even if the maximum rated voltage is applied to the fuse, the fuse is not allowed to generate a large amount of heat and should not be blown out. The fuse will only be blown out under abnormal conditions. The fuse needs to have excellent time delay characteristics. When the transient high voltage of the surge voltage passes through it, it is protected from being blown.

Figure 10 is a side view of a conventional fuse. Referring to Figure 10, the Korean Patent Application Publication No. 1992-0007019 (published on April 28, 1992) The patent discloses a fuse which is manufactured by inserting a temporary sleeve 6 having a bent portion 7 at one end, and interlocking with a glass creeper 8 at one end using a glass tube 1 having a filament 2 in the center; Returning the temporary sleeve 6, aligning the filament 2 in the glass tube 1, and moving the filament 2' in the glass tube 1 to temporarily align the filament 2 in the glass tube 1 to form a diagonal; the metal having the inner lead 4 The cap 3 is disposed at both ends of the glass tube 1, and the metal cap 3 is welded to the ends of the temporarily aligned filaments 2 by using the soldering iron 9 in the glass tube 1, forming a diagonal line.

However, this conventional fuse uses a glass tube, and the glass tube is joined by soldering, so the durability is low. In addition, since the inner leads are inserted in the glass tube, the filament length is limited. Therefore, conventional filaments do not provide sufficient time delay for high voltage operation.

Therefore, in view of the above problems, the present invention provides a fuse having a surface-attached fuse having the use of a ceramic material having a preferable mechanical strength to form a non-conductive member and a solder ring for bonding the ceramic tube and each of the sealing electrodes. For better durability, the present invention also provides a method of manufacturing the surface-attached fuse.

The present invention provides a fuse. Since the fusible element wound on the outer surface of the non-conductive element has a sufficient length and a sufficient number of turns, the time delay characteristic can be improved, so that the surface can be stably operated at a high voltage against the fuse, and the present invention also provides The surface is attached to the manufacturing method of the fuse.

The present invention provides a fuse capable of improving the wetting characteristics and joint strength of a weld ring, which is achieved by forming a plating layer on a welded joint, and the present invention also provides a method of manufacturing the fuse.

The present invention provides a fuse, the fuse includes a ceramic tube; a pair of sealing electrodes are disposed at both ends of the ceramic tube; the fuse unit is disposed in the ceramic tube, electrically connected to the sealing electrode, and includes a non-conductive element, disposed in the non-conductive a terminal electrode at both ends of the conductive member and a fusible element electrically connected to the terminal electrode; and a plurality of solder rings disposed between the ceramic tube and each of the sealing electrodes. The ceramic tube is joined to the sealing electrode by a molten welding ring.

The non-conductive element may be cylindrical and composed of a ceramic material, and the fusible element is wound around the outer surface of the non-conductive element.

The weld ring may include an alloy containing copper (Cu), silver (Ag), and zinc (Zn).

Each of the sealing electrodes includes a contact portion that protrudes toward the inside of the ceramic tube and is inserted into the ceramic tube and is in contact with the fuse unit; and the face portion is joined to the welding ring.

The outer surface of the weld ring is disposed at a height equal to the outer surface of the ceramic tube, and the inner surface of the weld ring is disposed to extend toward the inside of the ceramic tube to be more internal than the inner edge of the ceramic tube.

The weld ring includes an outer portion that is joined to one end of the ceramic tube and an inner portion that is joined to one end of the fuse unit.

The surface-attached fuse further includes a plurality of soldering elements that melt between the contact portion and each of the terminal electrodes and bond the contact portion and the terminal electrode together.

The surface-attached fuse further includes a plating layer containing nickel (Ni) or titanium (Ti), and the plating layer is formed on at least one of the contact portion, the face portion and the terminal electrode, and is melted by a welding ring or a soldering member. Improve joint strength.

The invention provides a structure with a surface attached to a fuse, and a package The substrate is disposed on the substrate, and the surface is attached to the solder ball by a fuse, wherein the surface of the fuse comprises a ceramic tube; a pair of sealing electrodes are disposed at both ends of the ceramic tube; and the fuse unit is disposed in the ceramic tube Electrically connected to the sealing electrode, and comprising a non-conductive element, a terminal electrode disposed at both ends of the non-conductive element, and a fusible element electrically connected to the terminal electrode; and a plurality of welding rings disposed on the ceramic tube and each Seal between the electrodes. The ceramic tube is joined to the sealing electrode by a molten welding ring.

1‧‧‧ glass tube

2, 2'‧‧‧ filament

3‧‧‧Metal cap

4‧‧‧ lead

6‧‧‧ Temporary casing

7‧‧‧Bend

9‧‧‧Welding iron

100, 100a, 100b, 100c, 100d‧‧‧ fuses

110, 110a, 110b‧‧‧Fuse unit

111‧‧‧ Non-conductive components

115, 115a, 115b‧‧‧ fusible components

117, 117a‧‧‧ terminal electrode

120‧‧‧Ceramic tube

130, 130b, 135‧‧‧ sealing electrode

131‧‧‧Connected to the face

133, 133a‧‧Contacts

150‧‧‧welding ring

150a, 150b, 150c‧‧‧ welding rings

151‧‧‧ outer surface

152‧‧‧ inner surface

153‧‧‧External

154‧‧‧ Internal

155‧‧‧welding ring

160‧‧‧ welding elements

180, 181, 183, 185 ‧ ‧ plating

C‧‧‧室

G‧‧‧ gap

Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings in which: FIGS. 1A through 1C are side views of a fuse unit of the present invention; and FIG. 2 is a surface mount disclosed in the first embodiment of the present invention. Side view of the fuse; Fig. 3 is an exploded side view of the surface-attached fuse disclosed in the first embodiment of the present invention; and Fig. 4 is a side view of the surface of the fuse according to the second embodiment of the present invention; 4 is a side view of the surface of the fuse according to the third embodiment of the present invention; FIG. 6 is a side view of the fifth embodiment of the present invention; FIG. 7A and FIG. 7B are a fifth embodiment of the present invention; FIG. 8A to FIG. 8F are side views of an embodiment of the present invention, illustrating a method of manufacturing a surface-attached fuse; and FIG. 9 is a surface-mounted fuse of the present invention disposed on a substrate a side view of the surface; Figure 10 is a side view of a conventional fuse structure.

The invention will be described below in conjunction with the drawings.

When the detailed description of the related art can avoid unnecessary confusion of the subject matter of the present invention, the description thereof will be omitted. In addition, the following terms, the definition of which takes into account the functions of the present invention, may vary depending on the user's intention or judicial precedent. Therefore, the meaning of each term should be interpreted based on the entire disclosure of this specification.

1A to 1C are side views of the fuse unit of the present invention. Fig. 2 is a side view showing the surface of the fuse according to the first embodiment of the present invention. Fig. 3 is an exploded side view showing the surface-attached fuse of the first embodiment of the present invention.

As shown in FIGS. 1A through 3, the surface-attachment fuse 100 disclosed herein generally includes a ceramic tube 120, a sealing electrode 130, a fuse unit 110, and a solder ring 150.

For example, the surface-attached fuse 100 of the present invention includes a ceramic tube 120 filled with an inert gas; a pair of sealing electrodes 130, the sealing electrode 130 is disposed at both ends of the ceramic tube 120; and the fuse unit 110, the fuse unit 110 is disposed at The ceramic tube 120 is electrically connected to the sealing electrode 130 and includes a fusible element 115; and a welding ring 150 sealed between the ceramic tube 120 and each of the sealing electrodes 130.

Referring to FIG. 1A, the fuse unit 110 of the present invention includes a non-conductive element 111; a terminal electrode 117, the terminal electrode 117 is disposed at both ends of the non-conductive element 111; and a fusible element 115, a fusible element 115 and a terminal electrode 117 Electrical connection.

The non-conductive element 111 may be cylindrical and may be constructed of a ceramic material such as aluminum. Further, the fusible element 115 is disposed on the outer surface of the non-conductive element 111.

The terminal electrode 117 may be made of a copper alloy and disposed at both ends of the non-conductive element 111 to electrically connect the sealing electrode 130 and the fuse unit 110.

The fusible element 115 is spirally wound around the outer surface of the non-conductive element 111. Since the length of the fusible element 115 is longer than the lengths of the fusible elements 115a and 115b of FIGS. 1B and 1C, the time delay characteristic of the protective surface against the fuse 100 being not blown by the surge voltage is improved. Therefore, the surface of the fuse 100 can be stably operated at a high voltage of, for example, 250 volts (or higher).

When an overcurrent is applied to the fusible element 115, the fusible element 115 is blown (opened). In addition, for example, the fusible element 115 may be made of copper (Cu), silver (Ag), copper-silver alloy, nickel-copper alloy, nickel-iron alloy, copper surface silver plating, iron, chromium (Cr), and the main component is nickel. iron alloy.

Further, referring to FIG. 1B, the fuse unit 110a of the present invention includes a hollow cylindrical non-conductive element 111; a terminal electrode 117 having end electrodes 117 disposed at both ends of the non-conductive element 111; and a fusible element 115a, fusible The element 115a is electrically connected to the terminal electrode 117 and passes through the non-conductive element 111.

Further, referring to FIG. 1C, the fuse unit 110b of the present invention includes a non-conductive element 111; a terminal electrode 117 having a terminal electrode 117 disposed at both ends of the non-conductive element 111; and a fusible element 115b having a length along the length of the fusible element 115b The direction is disposed on the outer surface of the non-conductive element 111 to be electrically connected to the terminal electrode 117.

Therefore, the fuse unit 110, 110a and 110b disclosed in the present invention It can be formed in a variety of shapes depending on the purpose and specificity of the product.

The ceramic tube 120 disclosed in the present invention has a cylindrical outer shape and is composed of a ceramic material. The cylindrical ceramic tube 120 has a sealing electrode 130 at both ends and is sealed by a sealing electrode 130. Further, both ends of the ceramic tube 120 are assembled through the solder joint and the sealing electrode 130.

As described above, the sealing electrode 130 is disposed at both ends of the ceramic tube 120.

Further, for example, the sealing electrode 130 may be composed of a copper alloy.

For example, each of the sealing electrodes 130 may include a contact portion 133 that protrudes toward the inside of the ceramic tube 120 and is inserted into the ceramic tube 120 and is in contact with the fuse unit 110 and the joint portion 131 joined to the welding ring 150.

Since the contact portion 133 of the sealing electrode 130 protrudes inward, the sealing electrode 130 can be efficiently assembled to the welding ring 150 or the ceramic tube 120. Since the fuse unit 110 in the ceramic tube 120 is pressed during the soldering process, the electrical connection between the sealing electrode 130 and the contact portion 133 is improved.

The welding ring 150 of the present invention melts between the ceramic tube 120 and each of the sealing electrodes 130 as a filler metal, and the sealing electrode 130 serves as a body metal connecting the ceramic tube 120 and the sealing electrode 130 during soldering.

For example, the weld ring 150 may be composed of an alloy including copper (Cu), silver (Ag), and zinc (Zn).

Further, the soldering process is performed at a temperature higher than the melting point of the solder ring 150, as a filler metal, and is performed at a temperature lower than the melting point of the ceramic tube 120 and the sealing electrode 130 as a bulk metal.

The wetting characteristics used to indicate the affinity between the filler metal and the bulk metal are important factors influencing the solder joint. In other words, when the ceramic tube 120 and dense When the welded ring between the sealing electrodes 130 has poor wettability, the joint between them cannot be formed. Therefore, the present invention uses a ceramic material having excellent wetting characteristics and a filler metal to form the ceramic tube 120 accommodating the fuse unit 110, instead of using a glass material and a filler metal having poor wettability to form a ceramic tube.

In addition, since the welding ring 150 is wicked when it is melted on the surfaces of the ceramic tube 120 and the sealing electrode 130, the welded joint using the welding ring 150 has a good bonding strength and excellent shock resistance characteristics (such as vibration or other physics). phenomenon).

At the same time, the outer surface 151 of the weld ring 150 is disposed at the same height as the outer surface of the ceramic tube 120, and the inner surface 152 of the weld ring 150 is disposed to extend inside the ceramic tube 120 to a position more inside than the inner edge of the ceramic tube 120. .

As described above, since the ceramic tube 120 is made of a ceramic material of a preferable mechanical strength, and the soldering ring 150 is used to join the ceramic tube 120 and each of the sealing electrodes 130, the surface of the present invention is preferably attached to the fuse 100 with better durability. The surface of the fuse 100 can be stably operated at a high voltage.

Fig. 4 is a side view showing the surface-attached fuse 100a of the second embodiment of the present invention.

Referring to Fig. 4, the surface-attachment fuse 100a of the present invention further includes a soldering member 160 which connects each of the contact portions 133 with each of the terminal electrodes 117.

For example, the soldering element 160 can be plate shaped and can be composed of an alloy including copper (Cu), silver (Ag), and zinc (Zn).

Like the weld ring 150, the welding element 160 melts between the contact portion 133 and the terminal electrode 117, and joins the contact portion 133 and the terminal electrode 117 to one Start.

Therefore, by the soldering member 160, the fuse unit 110 can be more firmly engaged with the sealing electrode 130, thereby improving the durability of the surface against the fuse 100a.

Fig. 5 is a side view of the surface-attached fuse 100b according to the third embodiment of the present invention.

Referring to Fig. 5, the welding ring 150a of the present invention, which is attached to the fuse 100b, is joined to both the ceramic tube 120 and the fuse unit 110.

In other words, the weld ring 150a includes an outer portion 153 that engages one end of the ceramic tube 120; and an inner portion 154 that engages one end of the fuse unit 110 (eg, the terminal electrode 117).

Therefore, the thickness of the weld ring 150a may be greater than or equal to the thickness of the contact portion 133a. This is because when the thickness of the weld ring 150a is larger than the thickness of the contact portion 133a, the weld ring 150a is joined to the ceramic tube 120 and the terminal electrode 117 after melting.

Further, compared with the weld ring 150 of Fig. 2, the inner portion 154 of the weld ring 150a extends toward the inner portion, and the width of the contact portion 133a is narrower than that of the contact portion 133 of Fig. 2.

Fig. 6 is a side view showing the surface-attached fuse 100c of the fourth embodiment of the present invention.

Referring to Figure 6, the surface-attached fuse 100c of the present invention further includes a plating layer 180 to improve the wetting characteristics between the solder ring 150 or the soldering member 160 and the body metal.

For example, plating layers 180 (181, 183, and 185) are formed The contact portion 133, the contact portion 131 and the terminal electrode 117 are overlaid to improve the bonding strength of the solder ring 150 or the soldering member 160 by the melting process.

Further, the plating layer 180 may include nickel (Ni) or titanium (Ti), and may be composed of a compound such as Ni3P.

7A and 7B are side views of the surface-attached fuse 100d of the fifth embodiment of the present invention.

Referring to Figs. 7A and 7B, each of the sealing electrodes 130b of the present invention has a flat plate shape without protruding contact portions, and this feature is different from the sealing electrodes shown in Figs. 1 to 6 .

Further, the welding ring 150b has a flat plate shape so that it can be simultaneously joined to one end of the ceramic tube 120 and the terminal electrode 117 (Fig. 7A).

Further, the welding ring 150c has a hollow ring shape such that the sealing electrode 130b is in direct contact with the terminal electrode 117 (Fig. 7B).

A method of manufacturing a surface-attached fuse disclosed in the present invention will be described in detail below.

8A to 8F are side views showing an embodiment of the present invention, which illustrates a method of manufacturing the surface-attached fuse 100.

As described above, the surface-attachment fuse 100 formed by the manufacturing method of the present invention includes a ceramic tube 120 in which the fuse unit 110 is disposed, and the first sealing electrode 130 and the second sealing electrode 135 are respectively inserted into both ends of the ceramic tube 120. The fuse unit 110 is connected, and the first solder ring 150 and the second solder ring 155 are connected to the ceramic tube 120 and the first and second sealing electrodes 130 and 135, respectively.

First, referring to FIG. 8A, in step S1, a first seal is formed. Electrode 130. The first sealing electrode 130 includes a contact portion 133 that protrudes toward the inside of the ceramic tube 120 and is inserted into the ceramic tube 120 and engaged with the fuse unit 110; and the surface portion 131 that is joined to the welding ring 150.

Therefore, referring to FIG. 8B, in step S2, the first solder ring 150 and the ceramic tube 120 are sequentially stacked over the first sealing electrode 130.

The first solder ring 150 is disposed on the joint surface 131 of the first sealing electrode 130, and the ceramic tube 120 is disposed on the first solder ring 150.

Therefore, referring to FIG. 8C, in step S3, the fuse unit 110 is inserted into the ceramic tube 120.

The fuse unit 110 includes a non-conductive element 111; a first end electrode 117 and a second end electrode 117a, the first end electrode 117 and the second end electrode 117a are disposed at both ends of the non-conductive element 111; and the fusible element 115 The fuse element 115 is electrically connected to the first terminal electrode 117 and the second terminal electrode 117a.

The inserted fuse unit 110 has its first terminal electrode 117 disposed above the contact portion 133 of the first sealing electrode 130. A gap G or a space is formed between the inner surface of the first terminal electrode 117 and the non-conductive element 111. When the second sealing electrode 135 is joined (as will be described later), and through the welding process described in step S5, the pressure applied thereto causes the gap G or the space to disappear. The gap G or space may be naturally or artificially formed during the assembly of the fuse unit 110.

Then, referring to FIG. 8D, in step S4, the second solder ring 155 and the second sealing electrode 135 are sequentially stacked on the ceramic tube 120.

Before the solder joint is welded, the assembly surface is attached to the fuse 100 through steps S1 to S4.

Then, the surface that goes through steps S1 to S4 is covered with insurance. The wire 100 is disposed in the chamber C, and at step S5, the ceramic tube 120 and the first sealing electrode 130 and the second sealing electrode 135 are sealed by melting the first welding ring 150 and the second welding ring 155.

The step S5 can be carried out in the chamber C in which the inert gas is filled, and the sealed ceramic tube 120 is filled with an inert gas. In addition, the inert gas prevents oxidation of the fuse unit 110 and improves durability.

The surface is placed with the fuse 100 vertically placed into the chamber C standing longitudinally (Fig. 8E). The chamber C is heated to melt the first weld ring 150 and the second weld ring 155, thereby completing the joint (Fig. 8F).

The chamber C is heated to a temperature lower than the melting point of the first sealing electrode 130, the second sealing electrode 135 (the first and second sealing electrodes as the bulk metal) and the ceramic tube 120 to avoid dissociation of the bulk metal. The temperature of the heating can be adjusted in the range of 500 ° C to 850 ° C depending on the material of the first weld ring 150 and the second weld ring 155 . For example, when the composition of the first weld ring 150 and the second weld ring 155 is an alloy containing copper and silver (for example, Ag25Cu), the chamber C is heated to 800 ° C to 850 ° C. The fusible element 115 can be constructed of a material that does not blow after soldering, for example, a nickel-copper alloy or a nickel-iron alloy.

Further, when the first weld ring 150 and the second weld ring 155 are composed of an alloy containing silver, copper, zinc and tin, such as Ag ₅₆ CuZnSn, the soldering temperature is between 600 ° C and 650 ° C. Therefore, in addition to the nickel-copper alloy or the nickel-iron alloy, the fusible element 115 may be composed of copper, silver and a copper-silver alloy which are blown at 800 ° C to 850 ° C.

In other words, by reducing the soldering temperature of the first solder ring 150 and the second solder ring 155 from 800 ° C to 850 ° C to 600 ° C to 650 ° C The main elements of conventional fusible elements can also be used, such as copper, silver, copper-silver alloys and similar alloys. Therefore, there are many options for the constituent elements of the fuse. Further, at 800 ° C (or higher), the fusible element 115 is deteriorated by heat even if it is not blown. However, when the soldering process is carried out at a relatively low temperature of 600 ° C to 650 ° C, the efficiency and quality deterioration due to heat will be lowered.

Next, the heated first weld ring 150 and the second weld ring 155 are melted to join the surface of the body metal by capillary action in a sealed state, thereby reducing the thickness.

Fig. 9 is a side view showing the surface of the present invention in which the fuse 100 is placed on the surface of the substrate.

Referring to Fig. 9, the lead wires are not shown, and the sealing electrode 130 of the surface of the present invention is bonded to the solder ball by the sealing electrode 130 of the fuse 100. Thus, the fuse 100 can be a surface mount device (SMD).

As described above, the present invention discloses a method of manufacturing a surface-attached fuse, using a ceramic material having a better mechanical strength as a ceramic tube, and using a soldering ring to connect the ceramic tube and the sealing electrode, so that the bonding strength and durability of the surface against the fuse are as follows. Improved.

Further, by winding the fusible element around the outer surface of the non-conductive element, the time delay characteristic can be improved, so that the surface can be stably operated at a high voltage with the fuse attached thereto.

Further, by lowering the temperature of the soldering process to a range of 600 ° C to 650 ° C, the fusible element is not blown even if a conventional material is used in the above temperature range.

As described above, the surface of the present invention is attached to a fuse A manufacturing method that manufactures a fuse having high durability and stable operation at 250 volts (or higher) through a soldering process.

As apparent from the above description, the present invention discloses a fuse and a method of manufacturing the same, which can be improved because a ceramic material having a better mechanical strength is used as the non-conductive member and a ceramic tube is used, and the ceramic tube and each sealing electrode are bonded using a welding ring. The durability of the fuse.

Further, the present invention discloses a fuse and a method of manufacturing the same, since the fusible element wound on the outer surface of the non-conductive member has a sufficient length and a sufficient number of turns, and the time delay characteristic can be improved, so that the fuse can be stably operated at a high voltage.

Further, the present invention discloses a fuse and a method of manufacturing the same, since the plating joint is provided with a plating layer, so that the wetting property and the joint strength can be further improved.

The preferred embodiments of the present invention have been disclosed in the foregoing description in conjunction with the accompanying drawings, and those of ordinary skill in the art should be able to be able to make a few changes without departing from the scope and spirit of the invention and the scope of the claims. , additions, deletions and replacements.

100‧‧‧Fuse

110‧‧‧Fuse unit

111‧‧‧ Non-conductive components

115‧‧‧ fusible components

117‧‧‧ terminal electrode

120‧‧‧Ceramic tube

130‧‧‧Seal electrode

150‧‧‧welding ring

Claims (7)

A surface-attached fuse includes: a ceramic tube; a pair of sealing electrodes disposed at both ends of the ceramic tube; a fuse unit disposed in the ceramic tube, electrically connected to the sealing electrodes, and including a non- a conductive element, a plurality of terminal electrodes disposed at opposite ends of the non-conductive element, and a fusible element electrically connected to the terminal electrodes; and a plurality of solder rings disposed on the ceramic tube and each of the sealed electrodes And wherein the ceramic tube is joined to the sealing electrodes by melting the welding ring, and wherein an outer surface of the welding ring is disposed at an upper level with an outer surface of the ceramic tube, and one of the welding rings The inner surface is disposed to extend toward the inside of the ceramic tube to be more internal than one of the inner edges of the ceramic tube. The surface-attached fuse according to claim 1, wherein the solder ring comprises an alloy containing copper (Cu), silver (Ag) and zinc (Zn). The surface-attached fuse according to claim 1, wherein each of the sealing electrodes includes a contact portion that protrudes toward the inside of the ceramic tube and is inserted into the ceramic tube to be in contact with the fuse unit; A face is joined to the weld ring. A surface-attachable fuse according to claim 1, wherein the weld ring includes an outer portion that is joined to one end of the ceramic tube and an inner portion that is joined to one end of the fuse unit. The surface-attached fuse according to claim 3, further comprising a plurality of welding elements, wherein the welding elements are at the contact portion and each of the ends The electrodes are melted and the contact portion and the terminal electrode are joined together. The surface-attached fuse according to claim 5, further comprising a plating layer containing nickel (Ni) or titanium (Ti), the plating layer being formed on the contact portion, the connecting portion and the terminal electrode On top of one, the joint strength is improved by the welding ring or the melting process of the welding element. A structure having a surface-attached fuse, comprising: a substrate; a solder ball disposed on the substrate; and a surface attached to the fuse, connected to the solder ball, wherein the surface of the fuse comprises: a ceramic tube; The sealing electrode is disposed at two ends of the ceramic tube; a fuse unit is disposed in the ceramic tube, electrically connected to the sealing electrodes, and includes a non-conductive element disposed at two ends of the non-conductive element a plurality of terminal electrodes, and a fusible element electrically connected to the terminal electrodes; and a plurality of welding rings disposed between the ceramic tube and each of the sealing electrodes, wherein the ceramic tube is melted by melting the welding ring Engaging with the sealing electrodes, and wherein an outer surface of the welding ring is disposed at an upper level with an outer surface of the ceramic tube, and an inner surface of the welding ring is disposed to extend toward the interior of the ceramic tube to One of the inner edges of the ceramic tube is more internal.