KR20140060744A

KR20140060744A - Printed circuit board having a pad bonding structure

Info

Publication number: KR20140060744A
Application number: KR1020120127435A
Authority: KR
Inventors: 신동민
Original assignee: 삼성전기주식회사
Priority date: 2012-11-12
Filing date: 2012-11-12
Publication date: 2014-05-21

Abstract

Disclosed is a printed circuit board (PCB) including a pad bonding structure. The printed circuit board including a pad bonding structure comprises a flexible PCB which is extended to be formed on one side of a first element; a first pad which is formed on the upper part of the flexible PCB; and a SUS which is formed on the lower part of the flexible PCB to transmit heat from the outside to the first pad.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a printed circuit board having a pad bonding structure,

The present invention relates to a printed circuit board having a structure for bonding pads formed on each element to electrically connect the separated first element and the second element.

Most of the IT devices such as mobile phones and notebooks, which are recently manufactured and sold for the purpose of video call and photo shooting, are equipped with camera modules.

In general, a high-resolution camera module has auto focusing function to obtain a clear image regardless of the distance of the subject to be photographed.

In order to perform the auto focusing function, an actuator for moving the lens through a mechanical operation and an actuator driving unit for providing a driving signal for operating the actuator are provided. In order to transmit and receive signals between the actuator and the actuator, do.

FIG. 1 is a view showing an electrical connection process between an actuator and a PCB for driving an actuator according to the related art, and FIG. 2 is a view illustrating a defective shape generated when connecting an actuator and a PCB according to the related art.

As shown in FIG. 1, in order to perform an auto focusing function, an electronic device having a camera module includes a first pad 115 provided on the actuator 110 and a second pad 115 provided on the PCB 120 for controlling the operation of the actuator The second pad 125 should be electrically connected and a bonding material such as solder and a conductive bond is used for electrical connection between the first pad 115 and the second pad 125. [

However, such bonding process deteriorates the workability and leads to poor productivity. In addition, since the joining operation is not easy, quality problems such as connection failure occur or the bonding material applied is protruded to the outside, There is also a case where it is produced.

FIG. 2 illustrates a failure mode that occurs when the actuator and the PCB are connected.

In the pad bonding process according to the related art described with reference to FIG. 1, it is important to control the amount of solder during soldering, and if not correctly managed, failure of soldering or overcharge may occur.

Fig. 2 (a) is a view showing a failure type in which the solder is insufficient and is absorbed.

The solder is applied only to the pad 115 provided on one side of the actuator 110 or the pad 125 provided on one side of the PCB 120 if solder amount management is not properly performed in a very small space There are frequent cases in which no electrical connection is made between each other.

Fig. 2 (b) is a diagram showing a defective type of solder due to an excessively large amount of solder.

A solder resist (SR) may be formed around the pad 125 of the actuator 120 connected to the pad 115 provided at one side of the PCB 110. However, the height of the solder resist (SR) However, there are cases where solder resist is not formed.

Accordingly, when the solder is too much, the solder may be protruded outward or the solder may be over-exposed to cause a short circuit with the surrounding pads 115 and 125.

Thus, in joining the pads of the first element (e.g., PCB 120) with the pads of the second element (e.g., actuator 110) using a bonding material such as solder or a conductive bond, It is required to prevent the occurrence of defects due to shortage or overage.

Korean Patent Publication No. 2008-0112172

The present invention relates to a method of bonding a pad formed on one side of a first element and a pad formed on a side of a second element by using a bonding material (for example, solder, conductive bond, etc.) And a pad bonding structure for preventing a defect caused by the pad bonding structure from being generated.

The present invention is to provide a printed circuit board having a pad bonding structure that allows a bonding process through pads of each element to be performed automatically in a packaging process without manually proceeding.

Other objects of the present invention will become readily apparent from the following description.

According to an aspect of the present invention, there is provided a printed circuit board having a pad bonding structure, comprising: a flexible PCB extended from one side of a first element; A first pad formed on the flexible PCB; And a pad (SUS) formed on a lower portion of the flexible PCB to transmit heat applied from the outside to the first pad.

Wherein a bonding material is disposed on the whole or a part of the upper portion of the first pad, a second pad formed on the second element is disposed on the upper portion of the first pad, heat input from the heating block contacting the cushion is transferred to the first pad So that the first pad and the second pad are electrically connected to each other through the bonding material.

The first element may be a PCB constituting a camera module, and the second element may be an actuator constituting the camera module.

The bonding material may be at least one of a solder and a conductive bond.

Other aspects, features, and advantages will become apparent from the following drawings, claims, and detailed description of the invention.

According to the embodiment of the present invention, when the pad formed on one side of the first element and the pad formed on the one side of the second element are electrically connected by using a bonding material (for example, solder, conductive bond or the like) It is possible to prevent the occurrence of defects due to insufficient or excesses.

In addition, there is also an effect that the bonding process through the pads of each element can be performed automatically in the packaging process without proceeding manually.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an electrical connection process between an actuator and a PCB for driving an actuator according to a related art; FIG.
FIG. 2 is a view illustrating a defective shape generated when a conventional PCB is connected to an actuator. FIG.
3 illustrates a printed circuit board having a pad bonding structure according to an embodiment of the present invention.
4A and 4B illustrate a pad bonding process according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

The present invention also relates to a printed circuit board having a pad bonding structure for connecting pads provided on each of two or more elements to electrically connect to each other. Hereinafter, for convenience of explanation, And a camera module having an actuator as a second element will be described as an example. However, it is apparent that the printed circuit board having the pad bonding structure according to the present invention is not limitedly applied to the camera module.

FIG. 3 is a view illustrating a printed circuit board having a pad bonding structure according to an embodiment of the present invention, and FIG. 4 is a view illustrating a pad bonding process according to an embodiment of the present invention.

3, a flexible PCB (FPCB) 320 is formed on one side of the PCB 310, and a pad 115 formed on one side of the actuator 110 is electrically connected to the flexible PCB 320, The pad 330 is formed to be connected to the pad 330. FIG.

A lower portion of the flexible PCB 320 is formed with a SUS 340 for transferring heat to the pad 330 formed on the upper portion.

3, the PCB 310, on which the sensor S (for example, an image sensor) is mounted, is formed of a Rigid or RF PCB, The cushion 340 is attached to the lower surface of the flexible PCB 320 designed to have a two-layer structure so that heat is applied to the cushion 340 through the heating block 420 during the packaging process, Is soldered to the pad 115 of the actuator 110 arranged to be in natural contact in the packaging process.

4A and 4B, a process of bonding the pads 330 formed on the upper part of the flexible PCB 320 and the pads 115 formed on one side of the actuator 110 for electrical connection will be described.

4A, a soldering portion of a three-layer structure of the sash 340, the flexible PCB 320, and the pad 330 may be provided with a part or all of the exposed surface of the pad 330 in the SMT (surface mounting technology) (That is, placing the solder 410).

4B, the heating block 420 is brought into contact with the lower end of the sUSH 340 and the heat supplied by the heating block 420 flows through the sUSH 340 to the upper pad 330, The solder 410 is melted and bonded (soldered) to the pad 115 of the actuator 110 positioned to be in contact with the upper portion.

Here, the heating block 420 acts to apply heat to the saus 340, and the solder 410 and the pad 115 of the actuator 110 are stably conducted by the applied heat.

Conventionally, only one surface can be soldered. However, when a printed circuit board having the pad bonding structure according to the present embodiment is used, soldering can be performed automatically by double-sided soldering.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims And changes may be made without departing from the spirit and scope of the invention.

110: Actuator
115, 125, 330: pad
120, 310: PCB
320: Flexible PCB
340: SUS (SUS)
410: Solder
420: Heating block

Claims

A printed circuit board having a pad bonding structure,
A flexible PCB extending from one side of the first element;
A first pad formed on the flexible PCB; And
And a pad (SUS) formed on a lower portion of the flexible PCB to transmit heat applied from the outside to the first pad.

The method according to claim 1,
A bonding material is disposed on all or a part of the upper portion of the first pad, a second pad formed on the second element is disposed on the upper portion of the first pad,
And heat input from the heating block contacted with the scee is transferred to the first pad and is bonded to each other so that the first pad and the second pad are electrically connected through the bonding material. .

3. The method of claim 2,
Wherein the first element is a PCB constituting a camera module, and the second element is an actuator constituting the camera module.

3. The method of claim 2,
Wherein the bonding material is at least one of a solder and a conductive bond.