JPH0737639U - Thermal head - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if drive circuit elements with different pad arrangement directions are used, there is no need to create a conductive pattern according to them, and wire bonding can be performed on any drive circuit element. To [Structure] In the case of using a drive circuit element 6 in which the drive electrodes 41 and 4n at both ends thereof are electrically connected to each other between adjacent drive electrode groups 4 and the pad arrangement is in a staggered pattern,
In the case of using the drive circuit elements arranged in the position shown in (1) and having a staggered pad arrangement opposite to this, the mounting position is shifted by one pad.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a thermal head which is used in various printing devices such as printers and facsimile devices and which records on a recording paper by energizing a heating resistor.

[0002]

[Prior art]

 A schematic configuration of a conventional thermal head will be described with reference to FIGS. In these figures, 1 is a thermal head, 2 is a ceramic substrate, and a plurality of drive electrode groups 4 including a heating resistor 3, connection pads 11 and 12, a common electrode 5, a drive circuit (on the substrate 2). Alternatively, the diode array) elements 6 (61 to 6n) are provided with element connection pads 13 and 14 along the heating resistor 3. The pads 11 and 12 provided at one end of each drive electrode 4 and the pads 13 and 14 of the drive circuit element 6 are provided so as to face each other. Further, as shown in FIG. 5, a high-density and small-sized circuit element is obtained by arranging the pads 11 and 12 of the drive electrode 4 and the pads 13 and 14 of the drive circuit element 6 by a half pitch and arranging them in two rows. , Each formed in a staggered pattern. In this case, the pad row 11 of the drive electrodes 4 arranged and formed on the drive circuit element 6 side is connected to the pad row 13 of the drive circuit element 6 formed on the heating resistor 3 side by the bonding wire 15. Similarly, the pad row 12 of the drive electrodes 4 formed on the heating resistor 3 side is also connected to the pad row 14 of the drive circuit element 6 by the bonding wire 16. In FIG. 4, 7 is a connection terminal and 8 is a flexible printed circuit board.

In the bonding process, first, wire bonding of the pad rows 11 and 13 is performed. After that, the remaining pad rows 12 and 14 are wire-bonded. As described above, after the bonding wires 15 of the pad rows 11 and 13 are bonded and then the bonding wires 16 of the pad rows 12 and 14 are wire bonded, the wire bonding can be surely performed. This is because when the wire bonding of the bonding wires 15 and 16 is sequentially performed in a certain direction, the distance between the bonding wires 15 and 16 adjacent to each other is sufficiently smaller than the size of the bonding tool, so that the wire already formed is damaged by the bonding tool. Because it will disconnect.

By the way, there are a plurality of types of drive circuit elements 6 depending on the application, and therefore, the arrangement of the connection pads 13 and 14 is different depending on the circuit elements as shown in FIGS. 5 and 6. That is, the arrangement of the connection pads 13 and 14 in FIG. 6 is an inverted zigzag arrangement with respect to the arrangement of the connection pads 13 and 14 in FIG. Have the same staggered arrangement. Therefore, when the drive circuit element 6 of FIG. 6 having a pad arrangement different from the pad arrangement of the drive circuit element 6 used in FIG. 5 is used in the thermal head of FIG. 5, as shown in FIG. , The pad rows 11 and 13 and the pad rows 12 and 14 correspond to each other, and wire bonding cannot be performed. Therefore, conventionally, every time the drive circuit element 6 used is changed, a conductor pattern corresponding to the drive circuit element 6 is formed, or a new drive circuit element is created in accordance with the conductor pattern of the head. I was dealing with it by choosing one of them.

[0005]

[Problems to be solved by the device]

 As described above, there are a plurality of types of drive circuit elements 6 depending on the application, and the arrangement of the pads 13 and 14 may be staggered or inverted zigzag depending on the drive circuit element. In that case, if a drive circuit element in which the pads 13 and 14 are arranged in a zigzag pattern is used in the head in which the pads 13 and 14 are arranged in a zigzag pattern, the pads 11 and 12 of the drive electrode 4 and the drive circuit are used. Correspondence between the pads 13 and 14 of the element 6 is reversed, and wire bonding cannot be performed. Therefore, conventionally, it is necessary to form a conductor pattern corresponding to the drive circuit element 6 each time the drive circuit element 6 used is changed or to newly create a drive circuit element according to the conductor pattern of the head. there were . However, if a conductor pattern corresponding to the drive circuit element 6 is formed or a new drive circuit element is formed in accordance with the conductor pattern of the head, the production thereof is troublesome and the manufacturing cost is significantly increased.

Therefore, the present invention has been made in view of the above conventional problems, and an object thereof is to form a conductive pattern corresponding to a driving circuit element having different pad arrangement directions. It is an object of the present invention to provide a thermal head that can be electrically connected to any drive circuit element without needing to do so.

[0007]

[Means for Solving the Problems]

 To achieve the above object, a thermal head according to the present invention comprises a heating resistor and a plurality of drive electrode groups in which one end is connected to the heating resistor and the connecting pads provided on the other end are in a staggered arrangement. And a drive circuit element having element connection pad groups arranged corresponding to the drive electrode groups and arranged in a staggered pattern corresponding to the connection pads of each drive electrode group. In the thermal head in which the connection pad of the drive electrode group and the element connection pad of the corresponding drive circuit element are electrically connected, the drive electrodes at both ends between the drive electrode groups are adjacent to each other. The drive electrodes of the drive electrode group are electrically connected to the drive electrodes at the ends of the drive electrode group, and the drive electrodes of the drive electrode group are formed by one more than the device connection pads of the corresponding drive circuit element.

[0008]

[Action]

 In the prior art, as shown in FIGS. 5 and 6, the drive circuit element 6 causes the connection pads 13 and 14 to be arranged in a staggered pattern and an inverted zigzag pattern. Therefore, when the drive circuit element 6 of FIG. 6 having a pad arrangement different from the pad arrangement of the drive circuit element 6 used in FIG. 5 is used in the thermal head of FIG. 5, as shown in FIG. The pad rows 11 and 13 and the pad rows 12 and 14 correspond to each other, and wire bonding cannot be performed. On the other hand, in the present invention, the mounting position is shifted by one pad between the case where the drive circuit elements having the zigzag pad array are used and the case where the drive circuit elements having the inverted zigzag pattern are used. Since it is mounted, it has a pad arrangement according to the drive circuit element and enables wire bonding. In that case, if the pad is displaced by one pad, the drive electrode at the end located on the side opposite to the shift side will not function because it is not connected to the drive circuit element via the connection pad. Therefore, in the present invention, the drive electrodes at both ends of the adjacent drive electrode groups are electrically connected to each other so that the function thereof is performed by the drive electrodes at the ends of the adjacent drive electrode group. There is no problem even if the drive circuit elements are arranged so as to be offset by one pad.

[0009]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. 1 is a component arrangement pattern diagram showing an embodiment of a thermal head according to the present invention, FIG. 2 is a component arrangement pattern diagram when a drive circuit element different from the pad arrangement of FIG. 1 is used, and FIG. 3 is A of FIG. FIG. It should be noted that, in the drawings, the same components as those in FIGS. This embodiment shows an example in which the heating resistor 3 is used in an edge type thermal head formed at the end of the ceramic substrate 2. In these figures, in this embodiment, the connection pads 13 and 14 of the drive circuit element 6 are formed in a staggered arrangement in the same manner as the conventional arrangement pattern shown in FIG. 5, and the adjacent drive electrode groups 4 (41 to 4n), the drive electrodes 41 and 4n at both ends thereof are electrically connected to each other, and when the drive circuit element 6 having a staggered pad arrangement is used, the drive circuit element 6 is connected as shown in FIG. By shifting the pad by one pad to the left, the element connection pads 13 and 14 are arranged in a zigzag pattern as in FIG. 5, and when using the drive circuit element 6 in which the pad array is an inverted zigzag pattern, As shown in Fig. 2, by disposing the drive circuit element 6 by shifting the mounting position by one pad to the right, the element connection pads 13 and 14 are arranged in an inverted zigzag pattern as in Fig. 6. Is. When a 64-bit element is used as the drive circuit element 6, a total of 65 connection pads 11 and 12 are formed.

When the drive circuit elements 6 having a staggered pad arrangement are used, as shown in FIG. 1, the connection pad 11 of the drive electrode 4n at the right end in the figure is connected to the corresponding drive circuit element 6. However, it is connected to the adjacent drive circuit element 6 on the right side via the drive electrode 41 located at the left end of the drive electrode group 4 on the right side adjacent thereto. On the other hand, when using the drive circuit elements 6 whose pad arrangement is an inverted zigzag pattern, as shown in FIG. 2, the connection pad 11 of the drive electrode 41 at the left end in the figure is connected to the corresponding drive circuit element 6. However, it is not connected, and is connected to the adjacent drive circuit element 6 on the left side through the drive electrode 4n located at the right end of the drive electrode 4 on the left side adjacent thereto. Other configurations are the same as those of the conventional head shown in FIGS.

Thus, in the thermal head having such a configuration, when the drive circuit elements 6 having different pad arrangements are used, the mounting positions thereof may be displaced by one pad, and thus the wire bonding may be performed. Therefore, it is not necessary to form a conductor pattern corresponding to the drive circuit element 6 or to create a new drive circuit element in conformity with the conductor pattern of the head. It can be commonly used for devices.

Although the embodiment has been described as applied to the edge type thermal head in which the heating resistor 3 is formed at the end of the ceramic substrate 2, the present invention is not limited to this, and the drive electrode is not limited thereto. The group 4 can also be applied to a thermal head of an alternating lead system in which both sides of the heating resistor 3 are provided.

[0013]

[Effect of device]

 As described above, according to the thermal head of the present invention, between the drive electrode groups adjacent to each other, the drive electrodes at both ends thereof are electrically connected to each other, and the drive circuit elements and the inverted zigzag pattern in which the pad arrangement is zigzag are formed. Since the mounting position of the drive circuit element is shifted by one pad, it is possible to electrically connect even if the drive circuit element with different pad arrangement is used. Therefore, the conductor pattern corresponding to the drive circuit element can be used. Does not have to be formed or a new drive circuit element is created in accordance with the conductor pattern of the head, and one conductor pattern is commonly used for two types of drive circuit elements with different pad arrangements. be able to.

[Brief description of drawings]

FIG. 1 is a component array pattern diagram showing an embodiment of a thermal head according to the present invention.

FIG. 2 is a component array pattern diagram when a drive circuit element different from the pad array of FIG. 1 is used.

FIG. 3 is an enlarged view of part A in FIG.

FIG. 4 is a schematic perspective view showing a component array of the thermal head.

FIG. 5 is a component array pattern diagram of a conventional thermal head.

FIG. 6 is a component array pattern diagram when a drive circuit element different from the pad array in the conventional thermal head is used.

[Explanation of symbols]

 2 Ceramic Substrate 3 Heating Resistor 4 Drive Electrode 5 Common Electrode 6 Drive Circuit Element 11 Connection Pad 12 Connection Pad 13 Connection Pad 14 Connection Pad 15 Bonding Wire 16 Bonding Wire

Claims (1)

[Scope of utility model registration request] 1. A heat generating resistor, a plurality of drive electrode groups each having one end connected to the heat generating resistor and connecting pads provided at the other end in a staggered arrangement, corresponding to each drive electrode group. And a drive circuit element having an element connection pad group arranged in a zigzag pattern corresponding to the connection pads of each drive electrode group. In a thermal head in which element connecting pads of corresponding drive circuit elements are electrically connected, drive electrodes at both ends between the drive electrode groups are electrically connected to drive electrodes at end portions of drive electrode groups adjacent to each other. The thermal head is characterized in that, when connected, the drive electrodes of the drive electrode group are formed by one more than the device connection pads of the corresponding drive circuit devices.