JPH05301366A - Print head and driving IC mounted on the print head - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a print head and a drive IC mounted on the print head, which can be downsized, the printing performance can be improved, and the yield in the manufacturing process can be improved. [Structure] A linear print medium 3 on the surface of a strip substrate 2,
A print head comprising: a plurality of driving ICs which are in charge of each part of the print medium 3 and drive the print medium 3, and in which connection terminals 5 are centrally arranged at both ends of a side edge of a substrate, A plurality of types of control signal wiring patterns 14 to 17 in which one end or both ends are electrically connected to a part of the connection terminal.
Are formed substantially linearly in the longitudinal direction of the substrate so as to go under each of the driving ICs, and control signals for control signals formed near the short sides of the driving ICs with respect to the control signal wiring patterns. The feature is that the pads are commonly connected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head and a driving IC mounted on the print head.

[0002]

2. Description of the Related Art The construction of a conventional thick film type thermal print head is disclosed in, for example, Japanese Utility Model Publication No. 2-80453. In such a traditional thermal print head, a heating resistor, a plurality of driving ICs for driving the heating resistor by dividing it by a predetermined length, and a signal for controlling each of the driving ICs. A comb-teeth-shaped terminal portion provided for connecting an input or a power supply is provided on the substrate. Then, this substrate is bonded on a support plate having a rigidity called a heat dissipation plate, and an external connection substrate called a flexible substrate which is in charge of a part of wiring with an external control circuit is formed on the lower surface of one side edge thereof. The comb-teeth-shaped terminal portion is overlapped with the comb-teeth-shaped terminal portion on the substrate to be stacked on the support plate. Then, in order to ensure the electrical continuity by constantly pressing the comb-teeth terminal portion of the external connection substrate and the comb-teeth terminal portion of the head substrate with an appropriate force, the external connection substrate A pressing cover is provided so as to be further stacked on top. The pressing cover is firmly fixed to the supporting plate over its entire length by a plurality of screws while sandwiching the external connection board therebetween.

A thermal print head having such a traditional structure requires a support plate and a pressing cover, which is stacked and fixed by a plurality of screws, in addition to the head substrate. There is a problem of getting bigger.

Further, since the support plate and the pressing cover are fixed to each other by a plurality of screws over the entire length of the external connection substrate while sandwiching the external connection substrate, the heat generated by the heating resistor during printing operation causes a so-called bimetal effect. There is also a problem that the entire head is bent.

A thermal print head having a structure in which the problem of flexural deformation in the structure of such a traditional thermal print head is reduced is disclosed in, for example, Japanese Utility Model Laid-Open No. 2-14.
No. 2038.

In the thermal print head disclosed in the publication, the connection terminal portions to be provided on the head substrate are centrally arranged in the central portion in the longitudinal direction, and accordingly, the length of the external connection substrate is shortened, Only in the central portion of the head substrate, the pressing cover and the support plate are firmly connected with the external connection substrate sandwiched therebetween. According to the thermal print head having such an improved structure, even if there is a difference in thermal expansion between the support plate and the pressing cover, mutual pressure contact is limited to the central portion in the longitudinal direction of the head. Since the bimetal effect does not affect the entire length of the print head, the problem of the bending deformation in the conventional thermal print head is remarkably reduced.

However, the above-described actual Kaihei 2-1
The improved thermal print head disclosed in Japanese Patent No. 42038 still has the following problems.

First, a basic structure in which a head substrate is still adhered to a support plate which still functions as a heat dissipation plate, an external connection substrate is overlaid thereon, and a pressing cover is further laminated and fixed. Therefore, there is a limit to the reduction of the dimension in the thickness direction, and it is not possible to meet the recent demand for further miniaturization of the thermal printing unit in the facsimile or printer device.

Second, since it is necessary to centrally arrange all the terminal portions in the central portion of the side edge of the head substrate, the common wiring pattern arranged along the heating resistor also bypasses both end portions of the substrate. It becomes necessary to wrap around the central portion of the side edge of the substrate, which increases the overall length of the common wiring pattern and increases the voltage drop in the common wiring pattern, which deteriorates the print quality.

Thirdly, as each driving IC, as shown in FIG. 6, a plurality of dot drive output pads are arranged in a row along one long side of the rectangular upper surface of the IC, while a control signal is provided. Since a pad having a structure arranged along the other long piece is adopted, a region between the drive IC array portion and the side edge of the head substrate is provided so as to establish conduction with these control signal pads. The wiring pattern to be formed becomes complicated, and therefore it is necessary to make a large area between the driving IC placement portion and the side edge of the head substrate on which the terminals are formed.
Therefore, the dimension of the head substrate, especially in the width direction, cannot be reduced beyond a certain level. As described above, such a tendency becomes greater because it is necessary to wrap the common wiring pattern around the central portion of the substrate side edge.

The present invention has been devised under the above circumstances, and a print head which can further reduce the width dimension and can be miniaturized, and a driving IC mounted therein. The task is to provide.

[0012]

In order to solve the above problems, the present invention takes the following technical means.

That is, in the print head according to claim 1 of the present application, the print medium is arranged on the surface of the strip-shaped substrate along a straight line parallel to one side edge of the substrate, and a predetermined todd of the print medium is arranged. A plurality of driving ICs, which are in charge of driving each number, are arranged along a straight line parallel to the arrangement direction of the print medium with an interval between them, while at the both ends in the longitudinal direction at the multiple side edges of the substrate, 1. A printhead comprising a plurality of connection terminals centralizedly provided for connection with an external control circuit, wherein the drive IC comprises first and second long sides and first and second long sides. It has a rectangular shape in plan view having short sides, a plurality of dot drive output pads are arranged along the first long side, and a plurality of types are provided near at least one of the short sides. Control signal pad A plurality of types of control signal wiring patterns, which are arranged and are electrically connected at one end or both ends to a part of the connection terminal, are formed substantially linearly in the longitudinal direction of the substrate so as to dive under the respective driving ICs. On the other hand, a control signal pad formed in the vicinity of the short side of the driving IC is commonly connected to each of the control signal wiring patterns. Next, the print head according to claim 2 of the present application is the same as the print head according to claim 1, wherein the plurality of driving ICs are arranged in an area shorter than an arrangement length of the print medium. It is characterized in that the connection terminals are arranged in a concentrated manner at both ends of the substrate in the longitudinal direction with a space left by the space.

Further, according to a third aspect of the present invention, in the print head according to the first or second aspect, the innermost terminal among the plurality of connection terminals centrally arranged at both ends in the longitudinal direction of the substrate is used. On the other hand, while forming a power ground terminal, a power ground wiring pattern for connecting the power ground terminals is formed in a strip-shaped region extending from the drive IC arrangement portion on the substrate to the other side edge of the substrate.
This power ground wiring pattern is used for each of the above driving ICs.
Is commonly connected to the power ground pad formed in the vicinity of the second long side.

Further, the invention described in claim 4 of the present application is a print head driving IC suitable for being mounted on the print head according to any one of claims 1 to 3, wherein the first and second long sides are included. It has a rectangular shape in plan view having first and second short sides, and a plurality of dot drive output pads are arranged along the first long side, and at least one of the short sides. A plurality of types of control signal pads are arranged in the vicinity of, and a power ground pad is formed in the vicinity of the second long side.

The control signal pads include a data-in pad, a data-out pad, a strobe pad, a logic power supply pad, and a clock pad. That is, the control signal pad generally means a pad other than the dot drive output pad and the power ground pad.

[0017]

First, in the print head of the present invention, the control signal pads of each drive IC are commonly connected to the wiring pattern formed so as to extend in the longitudinal direction of the substrate. Therefore, the number of connection terminals that should be concentrated on both ends of the board is extremely small,
Basically, the member corresponding to the external connection board becomes unnecessary.

Then, the support plate or the pressing plate, which is considered to be essential in the conventional example, is not essential for achieving the function of the print head in the print head of the present invention. Therefore, when the print head of the invention of the present application is used, it is possible to achieve a remarkable reduction in thickness as compared with the conventional case.

Further, according to the present invention, a plurality of types of control signal wiring patterns for connecting the connection terminals, which are centrally arranged at both ends of the board, are generally linear in the longitudinal direction of the board so as to go under each driving IC. And the control signal pads formed in the vicinity of the short side of the driving IC are commonly connected to the respective control signal wiring patterns. By doing so, firstly, since the signal wiring pattern becomes a simple linear shape, the step of connecting the pattern and the pad on the driving IC by, for example, wire bonding is simplified, and the manufacturing process is improved. Yield is improved. Secondly, by effectively utilizing the bottom of the drive IC placement portion, the region between the drive IC placement portion and the side edge of the substrate can be reduced, and the width of the substrate can be reduced. This allows the printhead to be further miniaturized.

Further, as in the print head according to the second aspect of the invention, a plurality of driving ICs are arranged in an area shorter than the arrangement length of the print medium, whereby a space is provided for the substrate. By arranging the connection terminals centrally at both ends in the longitudinal direction of the board, it is possible to prevent the array of the connection terminals and the array of the driving ICs from overlapping in the board longitudinal direction. The width of the print head can be further reduced, and the print head can be further downsized.

Further, when the power ground wiring pattern is formed in the area between the driving IC placement portion and the side edge of the substrate as in the print head according to the third aspect, another control signal wiring is provided. Since the pattern passes under each drive IC, the strip-shaped area between the arrangement portion of the drive IC and the side edge portion of the substrate can be a dedicated area for the power ground wiring pattern. Then, the width of the power ground wiring pattern can be made sufficiently wide, the voltage drop in the power ground wiring pattern can be suppressed as much as possible, and the printing quality can be maintained at a high level.

As described above, according to the print head of the present invention, the width dimension of the substrate can be reduced as compared with the conventional structure, and not only the size can be significantly reduced, but also the signal wiring pattern can be simplified. As a result, the yield in the manufacturing process can be improved, and the printing performance can be maintained at a high level, which is a remarkable effect.

By using the printhead driving IC described in claims 4 and 5, the above-described printhead of the present invention can be effectively formed.
After all, the same effect as the above will be exhibited.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described.
A specific description will be given with reference to FIGS. 1 to 5.

The embodiment shown in the figure is an example in which the present invention is applied to a thermal print head.
The same applies to the D print head and other print heads.

The illustrated printhead 1 comprises a head substrate 2 having a rectangular shape in plan view having a first longitudinal side edge 2a and a second longitudinal side edge 2b. A heating resistor 3 extending in the longitudinal direction along the first side edge 2a is formed on the upper surface of the substrate 2, and a plurality of driving ICs 4 ... Are formed along the second side edge 2b. Are arranged so as to extend in the longitudinal direction of the substrate while being spaced apart from each other. These drive ICs 4 ... are made of protective resin PRB.
Sealed by.

A plurality of connection terminals 5 are formed on the upper surface of the head substrate 2 at both ends of the second side edge 2b. A common wiring pattern 6 extending in the longitudinal direction of the substrate between the first side edge 2a and the resistor 3 is further formed on the upper surface of the head substrate. Both ends 6a, 6a of the common wiring pattern 6 are
It extends toward the second side edge 2b and forms one connection terminal in each connection terminal group.

In the present embodiment, each of the above driving ICs 4
The arrangement length L2 is set shorter than the length L1 of the heating resistor 3. The connection terminal groups 5 and 5 centrally arranged at both ends of the second side edge 2b of the substrate are formed at both ends of the substrate with a margin provided by the above arrangement. Therefore, each of the connection terminal groups 5 and 5 does not extend the length of the substrate 2 and the driving I
It is formed without overlapping the arrangement length of C4 ... In the longitudinal direction of the substrate.

On the other hand, in the arrangement of the plurality of driving ICs 4 ..., As shown in FIGS. 1 and 4, the two driving ICs in the center are spaced apart from each other more widely. The spacing is used to mount one thermistor 40 in the longitudinal center of the substrate 2. Since each end of the substrate 2 has a larger amount of heat dissipation, it is desirable to dispose the thermistor 40 in the center in this way for accurate temperature detection.

As shown in FIGS. 3 to 5, each drive I
Adjacent to the first side edge 2a side of C4 ...
A plurality of bonding pads 7 are formed on the upper surface of the head substrate 2. A large number of individual wirings 8 extend from the respective bonding pads 7 to the first comb-shaped teeth 9 that traverse under the heating resistor, while expanding. Second comb tooth 1
0 extends between the first comb-shaped teeth 9 so as to traverse under the heating resistor 3 and is commonly connected to the common wiring pattern 6. Therefore, the heating dots are defined by the spaces between the second comb teeth 10.

As shown in FIG. 3, the connection terminal group 5 arranged at the left end portion of the substrate 2 has two common terminals COM, a data-in terminal DI, a strobe terminal AEO, and a logic power supply from left to right. A terminal VDD, two thermistor connection terminals TM, and two power ground terminals PG are included. A plurality of the common terminals COM and the power ground terminals PG are provided so that a sufficient current can flow.

As shown in FIG. 5, the connection terminal group 5 arranged at the right end portion of the substrate 2 has two common terminals COM, data out terminals DO, clock terminals CLK, and strobe terminals from right to left. AEO, logic power supply terminal VD
D and three power ground terminals PG are included. The data-out terminal DO can be omitted. Further, the number of the common terminals COM and the power ground terminals PG can be increased or decreased according to various requirements, and other control signal terminals can be added.

Each common terminal COM is electrically connected to both ends 6a of the common wiring pattern 6. Each of the power ground terminals PG has a second side edge 2b of the head substrate 2.
Is connected to a power ground wiring pattern 11 that extends straight in the longitudinal direction of the substrate. In this embodiment, the power ground wiring pattern 11 has a relatively large width, and a relatively large current can flow therethrough.

One of the thermistor connection terminals TM is connected to a first thermistor wiring pattern 12 which extends substantially straight under each driving IC 4. The first thermistor wiring pattern 12 ends with the bonding pad 12a (FIG. 4) arranged in the center of the substrate 2 in the longitudinal direction. The other thermistor connection terminal TM is
It is connected to a second thermistor wiring pattern 12 ′ that extends substantially straight between the driving ICs 4 and the power ground wiring pattern 11. The second thermistor wiring pattern 12 'is a thermistor mounting pad 12a' arranged in the center of the substrate 2 in the longitudinal direction (FIG. 4).
It ends with. The thermistor 40 includes the mounting pad 12a 'of the second thermistor wiring pattern 12'.
It is mounted on the above and is connected to the bonding pad 12a of the first thermistor wiring pattern 12 by wire bonding.

Each strobe terminal AEO corresponds to each driving IC.
4 is connected to a strobe wiring pattern 15 that extends substantially straight below. However, as shown in FIG. 4, the strobe wiring pattern 15 is divided into left and right portions at a substantially central portion in the longitudinal direction of the substrate 2. That is, the left half of the strobe wiring pattern 15 is used only for the driving IC 4 arranged on the left half of the substrate, and the right half of the strobe wiring pattern 15 is arranged on the right half of the substrate. It is used for the IC4.

Each logic power supply terminal VDD is connected to each drive I
It is connected to a logic power supply wiring pattern 16 extending substantially straight under C4. However, the wiring pattern 16 is formed by bending in the substantially central portion of the substrate 2 so as to bypass the thermistor 40.

A single clock terminal CLK (FIG. 5) arranged at the right end of the head substrate 2 extends under each drive IC 4 substantially in the longitudinal direction of the substrate, and the leftmost drive IC ( It is connected to the clock wiring pattern 17 that ends in FIG. 3). The clock wiring pattern 17 extends almost straight under each IC 4, but is bent at a right angle at an appropriate portion to provide the bonding portion 17a.

The data-in terminal DI (FIG. 3) and the data-out terminal DO (FIG. 5) are similarly connected to the data wiring pattern 14 which is bent and formed so as to avoid other wiring patterns. The data wiring pattern 14 is discontinuous at the position of each driving IC 4. Instead, this data wiring pattern 14
Are cascade-connected to each driving IC 4.

As shown in FIG. 2, each driving IC 4
Has a long rectangular shape having first and second long sides 4a and 4b and first and second short sides 4c and 4d. In this drive IC, a large number of dot drive output pads TRO are arranged in a zigzag in two rows adjacent to the first long side 4a. These rod drive output pads are connected to the bonding pads 7 of the corresponding individual wirings 8 as shown in FIG.

As shown in FIG. 2, each driving IC
Are three power ground pads PG ^* , one data-in pad DI ^* , one data-out pad DO ^* ,
There are additional pads including one strobe pad AEO ^* , one logic power supply pad VDD ^* , one clock pad CLK ^* , two positioning pads KEY ^* , and one test pad TE ^* . Details of these additional pads are as follows.

The above three power ground pads PG
^{The *} is arranged in the vicinity of the second long side 4b of the driving IC 4 along the vicinity thereof. These power ground pads are
It is wire-bonded to the power ground wiring pattern 11 (FIGS. 3 to 5). The power ground pad PG ^* is driven so as to be easily wire-bonded to the power ground wiring pattern 11 arranged between the driving IC arrangement portion and the second side edge 2b of the head substrate 2. It should be understood that the number can be increased or decreased as long as it is in the vicinity of the second long side 4b of the IC 4 for use. The data-in pad DI ^* is arranged near the first long side 4a and the first short side 4c of the driving IC 4, while the data-out pad DO ^* is provided.
Are arranged in the vicinity of the first long side 4a and the second short side 4d of the driving IC 4. The data in pad and the data out pad DI, DO are wire-bonded to the discontinuous data wiring pattern 14 so as to cascade-connect the respective driving ICs.

The strobe pad AEO ^* is arranged near the first short side 4c of the driving IC 4. The position of the strobe pad AEO ^* can be selected so as to facilitate wire bonding in the longitudinal direction of the driving IC with respect to the strobe wiring pattern 15 formed so as to extend below the driving IC. of course,
The strobe pad AEO ^* can also be arranged near the second short side 4d of the driving IC.

The logic power supply pad VDD ^* is also
Arranged in the vicinity of the first short side 4c of the driving IC 4 so that the logic power supply wiring pattern 16 extending under the driving IC can be easily wire-bonded in the longitudinal direction of the driving IC. Has been done. Of course, this logic power supply pad VDD ^* can also be arranged near the second short side 4d of the driving IC.

One of the positioning pads KEY ^* is arranged near the first long side 4a and the first short side 4c of the driving IC 4, and the other positioning pad KEY ^* is the driving I.
It is arranged in the vicinity of the second long side 4b and the second short side 4d of C. These positioning pads are used for the head substrate 2
It is used only for the correct mounting of the driving IC to the given reference mark RM (FIGS. 3 to 5) above, so these pads are not wire bonded to any wiring pattern. Further, this positioning pad can be omitted. This is because the positional adjustment of the driving IC can be performed by utilizing the selected corner portion of the driving IC. It should be noted that such a locating pad is shown only in FIGS. 3 and 4 and is not shown in FIG. 5 for convenience of illustration.

The test pad TE ^* is the driving IC 4
Are arranged near the second long side 4b and the first short side 4c. This test pad is used only to inspect the performance of the driving IC before mounting. Therefore, this test pad is not wire bonded to any wiring pattern, and the position of this test pad is not important. This test pad can be omitted if desired. This is because this test pad has nothing to do with the operation of the driving IC.

The respective positions of the data-in pad DI ^* and the data-out pad DO ^* are at the data-in terminal D.
If the positions of I and the data-out terminal DO are interchanged, they can be interchanged accordingly. Similarly, the respective positions of the strobe pad AEO ^* , the logic power supply pad VDD ^* , and the clock pad CLK ^* (and the positioning pad KEY ^* and the test pad TE ^* ) are tentatively related to each other. 15-17 and related connection terminals AEO, VDD,
The positions can be swapped if the CLK is rearranged. The important thing is DI ^* , DO ^* , AEO ^* , VD
This means that the control signal pad including D ^* and CLK ^* is arranged adjacent to one or both of the two short sides 4c and 4d of the driving IC 4.

According to the embodiment shown in FIGS. 1 to 5, the connection terminal groups 5 are arranged in the marginal portions of the head substrate 2 and the wiring patterns 11 and 15 to 17 are respectively driven. Is commonly connected to the IC 4 for use. Therefore, this embodiment has the advantage that the number of connection terminals is reduced, that is, it is not necessary to use an external connection terminal to press it with a presser plate as in the structure of a traditional print head of the related art. It is possible to enjoy the advantage that the head can be made extremely thin. Furthermore, the printhead of this embodiment has the additional advantages described below.

First, each driving IC has its control signal pads DI ^* , DO ^* , AEO ^* , VDD ^* , and CLK.
^{Since *} is provided in the vicinity of the short sides 4c and 4d, the associated wiring patterns 14 to 17 extend below the driving IC, or in the vicinity of the first long side 4a of the driving IC. Can be formed. In other words, the control signal pads DI ^* , DO ^* , AEO ^* , VD
Wiring patterns 14 to 1 that cooperate with D ^* and CLK ^*
It is not necessary to provide 7 between the drive IC placement portion and the second side edge 2b of the substrate 2. Therefore, in order to form the power ground wiring pattern 11 with a sufficient width (when it is necessary to pass a relatively large current) over most of the above-mentioned strip-shaped portion (even if it has a narrow width). It can be used, or the width of the print head 1 can be reduced.

Second, the control signal pads DI ^* , D
Due to the above-described arrangement of O ^* , AEO ^* , VDD ^* , and CLK ^* , it is possible to form the wiring pattern for power ground 11 and the related wiring patterns 14 to 17 so as to extend as straight as possible. as a result,
The formation of these wiring patterns is extremely simplified, and the manufacturing efficiency and the yield can be improved. Furthermore, by reducing the bends and / or branches, the wiring pattern can be made as short as possible to reduce voltage drop and noise.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a print head according to an embodiment of the present invention.

FIG. 2 is a plan view of a driving IC suitable for mounting on the print head of FIG.

FIG. 3 is a partial plan view showing a left end portion of the print head of FIG.

FIG. 4 is a partial plan view showing a central portion of a similar print head.

FIG. 5 is a partial plan view showing a right end portion of a similar print head.

FIG. 6 is a plan view of a conventional printhead driving IC.

[Explanation of symbols]

1 Print Head 2 Head Substrate 3 Heating Resistor (Printing Medium) 4 Driving IC 5 Connection Terminal Group 4a (First Driving IC) Long Side 4b (Second Driving IC) Second Long Side 4c (Driving) First short side (of IC) 4d Second short side (of driving IC) DRO ^* Dot drive output pad DI ^* , DO ^* , AEO ^* , VDD ^* , CLK ^* Control signal pad 11, 14 to 17 control Signal wiring pattern PG ^* Power ground pad

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuno Kishimoto 21, Saizo Mizozaki-cho, Ukyo-ku, Kyoto ROHM Co., Ltd.

Claims (5)

[Claims] 1. A plurality of driving means for arranging a print medium on a surface of a strip-shaped substrate along a straight line parallel to one side edge of the substrate and driving the print medium for each predetermined number of todds. While the ICs are arranged along the straight line parallel to the arrangement direction of the print medium with an interval between them, a plurality of ICs are provided at both ends in the longitudinal direction of the multi-sided edge of the board for connection with an external control circuit. In a print head in which connection terminals are provided in a concentrated manner, the drive IC has a rectangular shape in plan view having first and second long sides and first and second short sides. A plurality of dot drive output pads are arranged along the first long side, and a plurality of types of control signal pads are arranged in the vicinity of at least one of the respective short sides, For one part of the connection terminal While forming a plurality of kinds of control signal wiring pattern to the generally straight in the longitudinal direction of the substrate so as to dive under the above drive IC across conducts, with respect to the respective control signal wiring patterns, said driving IC
A print head characterized in that control signal pads formed in the vicinity of the short side of the print head are commonly connected. 2. The plurality of driving ICs are arranged in an area shorter than the arrangement length of the print medium, and thereby, at both ends in the longitudinal direction of the substrate with a space left, 2. The printhead according to claim 1, wherein the connection terminals are arranged centrally. 3. Among the plurality of connection terminals centrally arranged at both ends in the longitudinal direction of the substrate, each innermost terminal is used as a power ground terminal, while the driving IC arranging portion on the substrate is connected to the substrate. A power ground wiring pattern for connecting the power ground terminals is formed in a strip-shaped region extending to the other side edge, and the power ground wiring pattern is formed near the second long side of each driving IC. The printhead according to claim 1, wherein the printhead is commonly connected to a ground pad. 4. A rectangular drive shape having a first and a second long side and a first and a second short side in plan view, and a plurality of dot drive outputs along the first long side. The pads are arranged, a plurality of types of control signal pads are arranged in the vicinity of at least one of the short sides, and a power ground pad is formed in the vicinity of the second long side. An IC for driving a print head, characterized in that 5. The printhead driving I according to claim 4, wherein the control signal pads include at least a data-in pad, a data-out pad, a strobe pad, a logic power supply pad, and a clock pad.
C.