Patent Publication Number: US-2022225495-A1

Title: Control circuit board

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to a control circuit board. 
     Description of the Related Art 
     In a control circuit board on which, for example, an integrated circuit is implemented, a pad group for testing is sometimes provided additionally on the board such that an operation test of the integrated circuit can be performed simply using an externally provided analysis apparatus. 
       FIG. 4  is a view exemplifying arrangement of pads on an existing control circuit board  1 . The control circuit board  1  includes a board  2  and a plurality of electronic parts  3 ,  4 , and  5  provided on a main surface of the board  2 . A plurality of pads  6  are provided on the main surface of the board  2  in such a manner that they keep away from the positions of the plurality of electronic parts  3  to  5 . 
     However, according to the control circuit board  1  depicted in  FIG. 4 , since the plurality of pads  6  are placed in a decentralized manner, man-hours for fixing connection terminals for external attachment to the individual pads  6  are required. 
     BRIEF SUMMARY 
     According to an embodiment of the present disclosure, there is provided a control circuit board including a board including a first surface and a second surface, wherein the first surface and the second surface are on opposite sides of the board, an integrated circuit disposed on the first surface of the board, and a pad group disposed on the second surface of the board and electrically connected to the integrated circuit through a through-hole formed in the board. 
     Preferably, a protective film having insulation removably covers the pad group. 
     Preferably, the pad group includes a plurality of pads that extend in a first direction and are placed at equal distances along a second direction that is perpendicular to the first direction. 
     The integrated circuit may be a touch integrated circuit (IC) that has a communication interface for communicating with an external apparatus and that, in operation, may perform driving control of a touch sensor, and the pad group may be electrically connected to the communication interface through the through-hole formed in the board and enable the external apparatus to perform to perform an operation test of the touch IC through the communication interface. 
     With the present disclosure, an external attachment work of an analysis apparatus through a pad group to the control circuit board can be performed easily. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a front elevational view of a control circuit board according to an embodiment of the present disclosure; 
         FIG. 2  is a partial enlarged view depicting a rear surface of the control circuit board of  FIG. 1 ; 
         FIG. 3  is a view depicting a state in which a flat cable is connected to the control circuit board of  FIG. 2 ; and 
         FIG. 4  is a view exemplifying arrangement of pads on an existing control circuit board. 
     
    
    
     DETAILED DESCRIPTION 
     In the following, an embodiment of the present disclosure is described with reference to the accompanying drawings. In order to facilitate understandings of the description, like components in the drawings are denoted by like reference signs as far as possible and overlapping description of them is omitted herein. 
     Configuration 
       FIG. 1  is a front elevational view of a control circuit board  10  according to an embodiment of the present disclosure. Referring to  FIG. 1 , the control circuit board  10  is configured such that it is connected to a capacitive touch sensor not depicted to detect a position on a touch surface thereof pointed to by a finger of a user or a touch pen. It is to be noted that the control target is not limited to a touch sensor but may be any of sensors of various detection types, various electronic parts, and various kinds of electronic equipment. 
     The control circuit board  10  includes a board  12  of a substantially rectangular shape elongated in one direction. On one of two main surfaces of the board  12 , an integrated circuit  16 , electronic parts  18  and  20 , and connectors  22  and  24  are provided. The main surface mentioned of the board  12  is hereinafter referred to as a “front surface  14 .” The integrated circuit  16  is a touch IC that has a communication interface for communicating with an external apparatus and performs driving control of the touch sensor and synchronous control of the touch pen through execution of firmware. The connector  22  is configured for connection to an X-axis cable of the touch sensor. The connector  24  is configured for connection to a Y-axis cable of the touch sensor. 
     Through-holes  26  and  28  are formed at corner portions of the board  12 . An inner wall of the board  12  surrounding each of the through-holes  26  and  28  is plated with copper. The integrated circuit  16  is connected to the through-holes  26  and  28  through printed wires not depicted. The through-holes  26  and  28  allow connection of the printed wires from the other main surface of the board  12  to the integrated circuit  16 . The other main surface mentioned of the board  12  is hereinafter referred to as a “rear surface  30 .” 
       FIG. 2  is a partial enlarged view depicting the rear surface  30  of the control circuit board  10  of  FIG. 1 . On the rear surface  30  of the board  12 , an aggregation of pads  32  and an aggregation of lead lines individually connected to one end of the pads  32  are provided. The aggregation of pads  32  and the aggregation of lead lines are hereinafter referred to as a pad group  34  and a lead line group  36 , respectively. 
     The pad group  34  is used in order to perform an operation test of the integrated circuit  16  through the communication interface of the integrated circuit  16 . The pad group  34  is placed densely at one place of the rear surface  30 . The plurality of pads  32  configuring the pad group  34  extend in a short side direction of the board  12  and are placed at equal distances along a long side direction of the board  12 . 
     Each of the lead lines configuring the lead line group  36  is connected at the other end thereof to the through-hole  26  described above. Consequently, the pad group  34  is electrically connected to the integrated circuit  16  through the through-hole  26 . The pad group  34  and the lead line group  36  are covered from above with a protective film  38  having insulation. The protective film  38  can be removed by a physical process or a chemical process. 
     Working Effect 
     The control circuit board  10  according to the present embodiment is configured in such a manner as described above. Now, a working effect by the control circuit board  10  is described with reference to  FIG. 3 . The operation test described above may be performed at any of timings including (1) a timing of analysis of a product with which some problem is found after shipment, (2) another timing of operation checking before shipment of a product, and (3) a further timing of debugging in development of firmware. 
       FIG. 3  is a view depicting a state in which a flat cable  40  is connected to the control circuit board  10  of  FIG. 2 . The flat cable  40  is a flexible connection cable for connecting an analysis apparatus not depicted to the control circuit board  10 . The flat cable  40  has, on the distal end side thereof, a connection terminal group in which connection terminals are placed at the same pitch as that of the pads  32 . 
     A worker would first remove part of the protective film  38  provided on the rear surface  30  of the control circuit board  10  to expose the pad group  34  to the outside. Then, the worker would perform positioning of the flat cable  40  and then press the connection terminal group of the flat cable  40  against the pad group  34 . Consequently, the connection terminal group of the flat cable  40  is fixed simultaneously and collectively to all of the pads  32  configuring the pad group  34 , and therefore, they can be connected simply to the external analysis apparatus. Then, if the worker leads out the flat cable  40  to the outside of the electronic equipment while the control circuit board  10  is incorporated into the electronic equipment, then the worker can perform an operation test of the integrated circuit  16  in a state close to an actual operation environment of the electronic equipment. 
     It is to be noted that the specifications of the pad group  34 , particularly the number, width, length, pitch, and so forth of the pads  32 , may be common or different according to the model of the touch sensor, the touch pen, or the electronic equipment. Especially, if the specifications of the pad group  34  are made common, then the convenience upon testing is improved. 
     As described above, the control circuit board  10  includes a board  12 , an integrated circuit  16  provided on a main surface  14  of the board  12 , and a pad group  34  placed densely at one place of the rear surface  30  of the board  12  and electrically connected to the integrated circuit  16  through a through-hole  26  or  28  formed in the board  12 . 
     Since the plurality of the pads  32  are placed densely at one place by using the rear surface  30  on which the integration density is relatively low in comparison with the front surface  14  on which the integrated circuit  16  is provided, it becomes easy to fix two or more pads  32  simultaneously and collectively to connection terminals for external attachment, in the example of  FIG. 3 , to the flat cable  40 . Consequently, the external attachment work of an analysis apparatus through the pad group  34  is facilitated in comparison with that in an alternative case in which a plurality of pads  32  are placed in a decentralized manner at different locations. 
     Further, the pad group  34  may be covered in a removable state with a protective film  38  having insulation. The protective film  38  suppresses malfunction and so forth of the integrated circuit  16 , which may possibly be caused by contact of the pad group  34  with a conductive part of the electronic equipment in which the control circuit board  10  is incorporated. Further, by removing the protective film  38  as occasion demands, the pad group  34  can be used timely. 
     Further, a plurality of pads  32  configuring the pad group  34  may extend in one direction (one side direction of the board  12 ) and be placed at equal distances along a direction perpendicular to the one direction (along the other side direction of the board  12 ). By the configuration, the control circuit board  10  can be connected simply to an external analysis apparatus through a flat cable  40  that has a connection terminal group in which connection terminals are placed at a pitch same as that of the pads  32 . 
     The integrated circuit  16  may be a touch IC that has a communication interface for communicating with an external apparatus and performs driving control of a touch sensor, and the pad group  34  may be used to perform an operation test of the touch IC through the communication interface. This configuration makes it possible to easily perform an operation test of the touch sensor. 
     It is to be noted that the embodiment of the present disclosure is not limited to the foregoing embodiment, and that various changes can be made without departing from the spirit of the present disclosure.