DE3603912A1 - Electronic network module and a method for producing the same - Google Patents

Abstract

According to the present invention, a moistureproof network module is formed from a plurality of electronic elements (2, 3), which are fitted on a substrate (1) having preformed electrodes (4) and from a plurality of conductor connections (5) which are connected to the electrodes (4). A moistureproof protective layer (7) is applied in such a manner that it covers or coats at least one electrode region of each electronic element (2, 3) so that the element (2, 3) cannot be short-circuited by moisture. The substrate (1) is fitted into a mould and is sealed, or is enclosed in a sealing manner, all round by injection moulding molten thermoplastic synthetic material into the moulding cavity around the substrate (1). In consequence, an electronic network module is created which can be sealed quickly by the outer seal (8) which is formed from thermoplastic synthetic material. <IMAGE>

Description

Electronic network component and method of manufacture

The same The present invention relates to an electronic one Network building block that is created by assembling a plurality of electronic elements, such as resistive elements and capacitors, on a substrate as well as through Isolating and sealing the substrate and electronic elements with one Plastic material is formed. The present invention also relates to a method for producing such a building block.

An electronic network component is a Composite device composed of a plurality of electronic elements such as resistance elements and capacitors integrated on a substrate. A network building block which is only made up of resistor elements is called a network resistor module and a network building block, which consists of a combination of resistance elements and capacitor elements is known as an RC network. The need for these network building blocks by integrating the mounting density can increase is with advances in integrated electronic circuits (IC's) and the miniaturization of electronic devices have risen sharply.

6 shows a sectional view of an already designed RC network, which is described as an example of an electronic network component. That Reference numeral 1 denotes a substrate, 2 a resistive layer, 3 a plate-shaped one Capacitor, 4 an electrode, 5 a conductor connection, and the reference number 6 denotes an outer seal.

In Fig. 6, the electrodes 4 are -on in a predetermined pattern printed on the substrate 1, which is made of an insulating material such as ceramic material or phenolic resin, and a plurality of resistance layers 2 and plate-shaped capacitors 3 are connected to each electrode 4.

Each resistive layer 2 is formed on the substrate 1 by thick film manufacturing techniques or thin film fabrication techniques, and then so trimmed respectively.

matched that it has a predetermined resistance.

Each plate-shaped capacitor 3 is on the substrate 1 through Soldering or the like mounted. The conductor connection 5 made of metal is attached to the end portion of each electrode 4 by soldering, and the substrate 1, the Resistance layers 2, the plate-shaped capacitors 3, the electrodes 4 and the conductor connections 5 are through the outer seal made of plastic material 6 sealed or enclosed in a sealed manner, with the exception of one protruding and outwardly leading part of each conductor connection 5. The outer seal 6 is provided for the purpose of protecting the resistive layers 2, the plate-shaped capacitors 3 and the electrodes a to protect and prevent penetration to prevent water or the like from getting inside. For this purpose, a thermosetting Plastic with a good sealing effect with respect to the conductor connections 5 as a material used for the seal or sealing cover 6. The outer seal 6 is formed by a known method such as powder coating, which is a process in which a heated substrate is inserted into a thermosetting plastic is put in powder form and is exposed to the heat of the heated substrate, molten plastic is then allowed to solidify, or else the outer seal 6 is formed by molding, which is a process in which a molten thermosetting plastic solidifies in a mold is left.

This sealing process creates an RC network with a high resistance generated against moisture.

However, the already designed module described above has the disadvantage that due to the use of a thermosetting plastic, the an essential material for preventing moisture from entering the Inside of the outer seal is, but its shaping takes a lot of time takes, the manufacturing cost is high.

It is possible to reduce the manufacturing cost by that you create a seal by means of a thermoplastic material, the one has short molding cycle, but thermoplastics generally have a poorer sealing effect with respect to metal, and when using a thermoplastic Plastic for the outer seal 6 there is a tendency that between the outer Seal 6 and the conductor connections 5 creates a gap, with the result that Water and the like can penetrate into the interior, causing short circuits between the electrodes 4 of the resistance layers 2 and the plate-shaped capacitors 3 as well as deterioration in circuit characteristics. this leads to especially problems if the resistance elements are not is platelet-shaped parts, and the resistance elements instead by film-making techniques are formed as a hybrid component on the substrate 1, the harmful influence of water or the like is so great that the resistance set by trimming is reduced.

It is an object of the present invention to provide one electronic network component, the outer seal of which is made of a thermoplastic Plastic is formed so that this module can be produced at low cost and at the same time an effective and inexpensive barrier against moisture creates.

A solution to this problem results from the characteristic of the claim 1.

The present invention provides an electronic network module, in which the above-described disadvantages of already conceived proposals are overcome and which has a moisture-proof protective layer, the at least one Covering the electrode area of each electronic element on the substrate, so that the elements cannot be short-circuited by moisture.

Preferred developments of the invention emerge from the subclaims.

The invention and further developments are described below based on partially schematic views of several preferred exemplary embodiments explained in more detail.

1 shows a sectional view of the internal structure of an exemplary embodiment an electronic network module according to the invention; Figures 2 (a) to 2 (e) are views to explain the manufacturing process for the embodiment shown in Fig. 1; Fig. 3 is a sectional view showing the internal structure of another embodiment an electronic network module according to the invention; Figures 4 (a) through 4 (e) are views to explain the manufacturing process for the embodiment shown in Fig. 3; Fig. 5 is a sectional view showing the internal structure of still another embodiment a network module according to the invention; and Fig. 6 is a sectional view of the interior Construction of an already designed electronic network module.

The embodiments of the present invention are now shown below Explained with reference to the accompanying drawings.

Fig. 1 is a sectional view showing the internal structure of an RC network according to an embodiment of the present invention. The reference number 7 denotes a moisture-proof protective layer and reference numeral 8 an outer one Sealing or sealing cover, and those parts that correspond to parts of the 6, have the same reference numerals. The resistive layers 2 and the electrodes 4 are in the respective desired patterns as shown in FIG the already designed module described above is the case on which printed substrate 1 formed of ceramic material or the like, and the plate-shaped Capacitors 3 and the conductor connections 5 are soldered to each electrode 4. After the resistor layers 2 have passed the predetermined trimming process have been subjected to the Resistive layers 2, the plate-shaped capacitors 3 and the electrodes 4 with the moisture-proof Protective layer 7 made of a plastic or the like that cures under UV light and also by the outer seal 8 made of a thermoplastic material sealed or enclosed in a sealed manner. As a result of this is self then when water or the like through the junctions between the outer Sealing 8 and the conductor connections 5 penetrates into the interior, ensures that the water or the like never short-circuit between the electrodes 4 of any resistance layer 2 and any plate-shaped capacitor 3 leads. This makes an RC network with good resistance to Created moisture.

The manufacturing method for the embodiment shown in FIG. 1 will now be explained with reference to Figs. 2 (a) to 2 (e).

First, the electrodes 4 are formed on the substrate 1, namely by printing a paste of silver palladium or the like on the substrate in a predetermined pattern, and a plurality of resistor layers 2 are made printed in such a way that they are arranged spanning electrode gaps are as shown in Fig. 2 (a).

After that, the substrate 1 is baked, and each resistor layer 2 becomes so qetrJitrrrL that it has a predetermined resistance, and A plate-shaped capacitor 3 is soldered in each of the further electrode gaps.

Then a plurality of conductor connections 5, which are connected to one with Transport holes provided, present in the form of a continuous strip Lead frames 9 are formed, attached to the substrate 1 and with the corresponding End portions of the electrodes 4 are soldered, as shown in Fig. 2 (b).

As shown in Fig. 2 (c), the substrate is poured into a molten, Plastic curing under UV light 10 submerged up to down to that by the line A-A (which the conductor connections 5 just above the Substrate 1 cuts) position indicated, and the plastic coating that cures under UV light is then cured by means of a UV lamp, creating the moisture-proof protective layer 7 is formed on the entire surface of the substrate 1 as shown in Fig. 2 (d) is.

The substrate 1 is then together with the lead frame 9 in the cavity a mold (not shown) and injected with a molten thermoplastic Sealed plastic in the cavity around the substrate 1 around.

Each conductor connection 5 is finally to the area where it connected to the lead frame 9, cut off, and thus an Rc network, through the outer seal 8 made of thermoplastic material in sealing Manner is completed as shown in Fig. 2 (e).

Thermoplastic plastic whose use as a material for the outer seal 8 considered difficult in the proposal already conceived can be used in the present embodiment because the electrode areas 4 of both the resistive layer 2 and the platelet-shaped Capacitor 3 are covered with the moisture-proof protective layer 7. as The result of this is that the molding cycle is shortened and molding in multiple forms or reusable forms, which reduces the costs per piece will.

Although in this embodiment the entire surface of the substrate 1 covered with the moisture-proof or moisture-proof protective layer 7 is, it is sufficient that at least that (common) electrode 4, the connected to each resistive layer 2 and each platelet-shaped capacitor 3 is, coated with the protective layer, as the purpose of moisture-proof Protective layer 7 consists in between the electrodes on both Ends of each resistance layer 2 and each plate-shaped capacitor 3 one To prevent short circuit.

Fig. 3 is a sectional view showing the internal structure of an RC network according to a further embodiment of the invention. The reference numeral 11 denotes a metal substrate and the reference numeral 12 a platelet-shaped resistor element, and those parts that correspond to parts of the embodiment shown in FIG correspond to have the same reference numerals.

In this embodiment, a metal substrate 11 is used, which is integrally formed with the conductor connections 5, and the platelet-shaped Resistance elements 12 and the plate-shaped capacitors 3 are predetermined Positions soldered to the substrate 11. The electrode areas 4 at both ends each plate-shaped resistance element 12 and each plate-shaped capacitor 3 are covered with the moisture-proof protective layer 7, creating the desired Circuit construction from a suitable combination of resistors and capacitors is achieved.

The rest of the structure is the same as that of the embodiment shown in FIG. The following is the manufacturing process for this embodiment in the appropriate order by reference to Figs. 4 (a) through 4 (e).

A frame body 13 having a predetermined configuration like this one shown in Fig. 4 (a) is first formed by making an in Flat piece of metal present in the form of a continuous strip successively exposing pressing or standing processes. The frame body 13 is formed from the substrate 11, which is made up of a plurality of interconnected lattice Electrodes 4 consists of the lead connections 5 and a lead frame area 14, in which a plurality of holes 14a are formed. the lowermost electrodes 4 on the substrate 11 and the lead frame area 14 are through the conductor connections 5 connected to one another.

Then, the plate-shaped resistance elements 12 and the plate-shaped Capacitors 3 are soldered to the electrodes 4, and from which the electrodes 4 together connecting areas, the unnecessary areas are cut away or punched away.

The substrate 11 is in the melted, curing under UV light Plastic 10 dipped down to the point indicated by line B-B (the which intersects the conductor connections 5 just above the electrode grid) in Fig. 4 (c) indicated position, and the plastic, which cures under UV light, is then by means of a UV lamp cured, whereby the moisture-proof protective layer 7 on the entire surface of the substrate 11 is formed as shown in Fig. 4 (d) is.

The substrate 11 is then together with the lead frame 14 in the Cavity of a mold (not shown) set and injected by a molten Thermoplastic plastic in the cavity around the substrate 11 is sealed.

Each conductor connection 5 is finally to the area where it connected to the lead frame 9, cut off, and thus an RC network, through the outer seal 8 made of thermoplastic material in sealing Manner is completed as shown in Fig. 4 (e).

In this embodiment one can thus on the step of Refrain from soldering the conductor connections 5 to the substrate 11, and the desired Circuit patterns can be obtained by drawing the relevant connection areas which cuts away electrodes, which are connected to one another in a grid form from the start or punch away.

Fig. 5 is a sectional view showing the internal structure of a network resistor according to an additional embodiment of the present invention. A majority of resistance layers 22, a plurality of electrodes 23 corresponding to these and a common electrode 24 are in the respective predetermined pattern formed on a substrate 23 made of ceramic material or the like. Conductor connections 25 are soldered to each electrode 23 and to the common electrode 24. After the resistor layers 22 have passed the predetermined trimming process have been subjected, the resistance layers 22, the plate-shaped Capacitors 23 and the common electrode 24 with a moisture-proof Protective layer 27 made of a plastic or the like that cures under UV light covered and also by an outer seal 28 made of a thermoplastic Plastic sealed or enclosed in a sealed manner.

Although in the above-described embodiments a Network resistance building block that only uses resistance elements, as well as a PC network using a combination of resistive elements and capacitors, have been explained as examples of electronic network components It is also possible to combine other electronic parts, such as a diode, with it.

From the above description it follows that according to the present invention short circuits between the electrodes of each electronic Elements can be prevented by the moisture-proof protective layer and moreover deterioration caused by penetration of water or the like or degeneration of the circuit characteristics is prevented. It is also more thermoplastic Plastic, which takes little time to form, as a material for the exterior Sealing or sealing cover can be used.

In this way, the present invention provides an electronic one Network component that can be manufactured more cheaply and is more resilient against moisture as already conceived proposals.

Claims (6)

Claims 1. Electronic component, characterized g e k e n n z e i c h n e t that a substrate (1) is provided on which a plurality of electronic Elements (2, 3) is attached, with electrodes (4) the electronic elements (2, 3) in a predetermined manner with each other with a plurality of conductor terminals (5) connect that a moisture-proof protective layer (7) at least one electrode (4) the electronic elements (2, 3) covered in a protective manner in such a way that prevents short-circuiting of the electronic elements (2, 3) due to moisture is that an outer seal (8) encloses the substrate (1), with a region each conductor connection (5) can protrude through this to the outside, and that the outer seal (8) consists of a thermoplastic material. 2. Electronic component according to claim 1, characterized in that that the moisture-proof layer (7) consists of a plastic that cures under UV light consists. 3. Electronic component according to claim 1 or 2, characterized in that that the moisture-proof layer (7) covers the entire surface of the substrate (1) covered. 4. A method for producing an electronic component with a moisture-proof layer, characterized by the following steps: applying a lead frame in the form of a continuous strip on the Substrate of the building block; coating the substrate as well as one in the vicinity of the substrate located area of the lead frame with a moisture-proof protective layer; Forming a thermoplastic outer seal around that coated with the protective layer Substrate around; and cutting the leadframe to form individual leads. 5. Method of manufacturing a moisture-proof electronic Network module, characterized by the following steps: Forming electrode areas as an integral part of one in the form of a continuous strip Lead frame; Attaching electronic elements to associated electrode areas; Cutting away unwanted areas of the leadframe between element attachment points to form a desired network; About pulling the formed network with a moisture-proof protective layer; Form a thermoplastic outer Sealing around the network covered with the protective layer; and cutting off of the lead frame to form individual connection leads. 6. The method according to claim 5, characterized in that the network coated by immersing it in a plastic that cures under UV light will.