Printing element board

Abstract

The invention relates to a printing element board. One embodiment of the present invention is a printing element plate including: a plurality of printing elements configured to eject a liquid, the plurality of printing elements being arranged in a first direction to form a printing element array; a heat generating element configured to heat the liquid; a driver configured to drive the heat generating element; a data processing circuit, which is configured to control the driver; and a plurality of PADs configured such that a signal to be transmitted to the data processing circuit is input from the outside to the plurality of PADs, the plurality of PADs being arranged in the first direction to form a PAD array, wherein the data processing circuitry is provided in at least two or more systems between the array of print elements and the array of PADs in a second direction orthogonal to the first direction.

Description

Technical Field

[0001] The present disclosure relates to a technology of a printing element board included in a printing device that performs printing by ejecting liquid. Background Art

[0002] In a printing element board used in a printing device that prints by ejecting liquid such as ink, with the recent demand for increased image quality and increased functions, temperature control for controlling the temperature of the printing element board is performed. In addition, in order to meet the demand, there is a trend of increasing the number of nozzles of the printing element board and increasing the frequency of driving the nozzles.

[0003] In the printing element board, the amount of droplets to be ejected and the ejection speed vary depending on the temperature. For this reason, in the case where a temperature distribution of the board temperature is generated, the temperature distribution causes image non-uniformity, so that the image quality is degraded.

[0004] Japanese Patent Laid-Open No. 2017-213874 discloses a method as a method for correcting temperature distribution of a board, the method comprising: installing a driver of a sub-heater in a specific area in a printing element board; and selecting and heating one or more of the areas to suppress temperature unevenness in the board. Summary of the invention

[0005] However, the configuration of Japanese Patent Laid-Open No. 2017-213874 is a configuration of a system including only a data processing circuit, in which data for selecting and driving a sub-heater is input by externally inputting data, and this configuration cannot fully meet the aforementioned requirements for increased image quality and increased functionality.

[0006] In the configuration of one system including a data processing circuit, the wiring connecting the data processing circuit to the switch configured to drive all the sub-heaters becomes long, making the layout on the board complicated. In addition, regarding the input of data to such a configuration, basically such a configuration can only adopt one communication channel. Then, in the case of driving a large number of sub-heaters, the number of pieces of data to be input increases, so the increase in frequency cannot be achieved.

[0007] In view of this, an object of the present disclosure is to provide a configuration of a printing element board capable of reducing wire resistance, improving layout, and achieving an increase in frequency compared with a conventional configuration.

[0008] One embodiment of the present invention is a printing element board, which includes: a plurality of printing elements, the plurality of printing elements being configured to eject liquid, the plurality of printing elements being arranged in a first direction to form a printing element array; a heat generating element, the heat generating element being configured to heat the liquid; a driver, the driver being configured to drive the heat generating element; a data processing circuit, the data processing circuit being configured to control the driver; and a plurality of PADs, the plurality of PADs being configured so that a signal to be sent to the data processing circuit is input from the outside to the plurality of PADs, the plurality of PADs being arranged in the first direction to form a PAD array, wherein the data processing circuit is provided in at least two or more systems between the printing element array and the PAD array in a second direction orthogonal to the first direction.

[0009] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1A and Figure 1B is a perspective view of a liquid ejection head;

[0011] FIG. 2A to FIG. 2D It is a plan view of the printed component board;

[0012] Figure 3 is a diagram showing the layout of a printing element board;

[0013] Figure 4 is a diagram showing the configuration of a sub-heater driving circuit;

[0014] Figure 5 is a block diagram in the case where a sub-heater control signal is generated in a printing element board;

[0015] Figure 6 is a diagram showing a four-layer structure of a wiring layer in a printing element board;

[0016] 7A to 7F is a diagram showing a detailed configuration of a sub-heater;

[0017] FIG. 8A to FIG. 8C is a diagram showing a detailed configuration near a heater (in the case where the sub-heater material is polysilicon);

[0018] 9A to 9C is a diagram showing a detailed configuration near the heater (in the case where the sub-heater material is the heater material);

[0019] Fig.10 is a block diagram showing the configuration of a liquid ejection head;

[0020] Fig.11 is a timing diagram of data and signals to be input to the printed component board;

[0021] Fig.12 is a diagram showing the configuration of print data (packet) Dt for one transmission;

[0022] Fig.13 is a diagram showing the contents of the additional information designation section (Inf12);

[0023] Fig.14 is a diagram showing the configuration of print data in this embodiment;

[0024] Fig.15 is a diagram showing the configuration of sub-heater selection data;

[0025] Fig.16 is a diagram for explaining data input to a printing element board; and

[0026] Fig.17A and Fig. 17B is a diagram for explaining the effect of using two communication channels. DETAILED DESCRIPTION

[0027] [First embodiment]

[0028] Hereinafter, the liquid ejection head according to the present embodiment and the printing element plate included in the liquid ejection head will be described with reference to the accompanying drawings. It is noted that the following embodiments are not intended to impose unnecessary restrictions on the invention according to the claims. In addition, although a plurality of features are described in the following embodiments, all of the plurality of features are not necessarily essential for solving the problem disclosed herein, and a plurality of features may be combined in any manner. Moreover, in the accompanying drawings, the same or similar configurations are represented by the same reference numerals, and repeated descriptions are omitted in some cases.

[0029] Figure 1A and Figure 1B is a simplified perspective view showing the appearance of the liquid ejection head in this embodiment. Figure 1A There is shown a liquid ejection head 100 in which a plurality of printing element boards 101 are arranged side by side. This liquid ejection head is a type generally called a "line head".

[0030] Figure 1B The liquid ejection head 100 is shown in which two printing element boards 101 are arranged side by side with Figure 1AAnother form different from the form in the embodiment. This liquid ejection head is generally called a "serial head". Note that, although the case where the liquid ejection head has two printing element plates is shown in this example, the liquid ejection head in the serial head form generally includes one or two printing element plates.

[0031] FIG. 2A to FIG. 2D : is a plan view showing the shape of the printing element board 101 in this embodiment. Figure 2A The printing element board 101 has a parallelogram shape, in which a plurality of PADs 102 as electrical input and output portions are provided along one of the two longer sides of the parallelogram so that a PAD array is formed in parallel with the one side. The PAD 102 is for transmitting data to be sent to a data processing circuit (see Figure 3 ) is input from the outside to the electrodes of the printing element board 101.

[0032] Figure 2B The printing element board 101 has a parallelogram shape in which a plurality of PADs 102 are provided along each of two longer sides of the parallelogram so that two PAD arrays are formed.

[0033] Figure 2C The printing element board 101 has a rectangular shape in which a plurality of PADs 102 are provided along one of two longer sides of the rectangle so that a PAD array is formed in parallel with the one side.

[0034] Figure 2D The printing element board 101 has a rectangular shape in which a plurality of PADs 102 are provided along each of two longer sides of the rectangle so that two PAD arrays are formed.

[0035] Note that the shape of the printed component board is generally FIG. 2A to FIG. 2D The shape of the printing element board may be any of the shapes of, but is not limited to these. For example, the shape may be a trapezoid, and the PAD 102 may also be arranged in various ways. The shape of the printing element board only needs to be a quadrilateral consisting of long sides and short sides.

[0036] Figure 3 1 is a diagram showing the layout of the printing element board in this embodiment. In the board end portion of the printing element board 101, a plurality of PADs 102 are provided side by side in the Y direction. These PADs 102 include signal terminals through which data for selecting nozzles to eject ink is received, power supply terminals, and the like.

[0037] The printing element board 101 includes a plurality of heaters 103. The heater 103 is a printing element for ejecting liquid such as ink. In this example, the plurality of heaters 103 are arranged in the Y direction, and arrays A to D are provided as heater arrays (also referred to as printing element arrays).

[0038] The printing element board 101 is provided with ink supply ports 106 for supplying ink to be ejected from the nozzles along the heater array, and the ink having flowed in from the ink supply ports 106 is supplied to the upper portion of the heater 103 .

[0039] The ejection port 205 (see Figure 8B and Fig. 9B ) is disposed just above the heater 103, and current is caused to flow into the heater 103 at a desired timing to heat the ink or to cause the ink to bubble and eject ink droplets from the ejection port 205. Note that this embodiment is described using a heater as an example of an ink ejection element, but a configuration in which ink is ejected by pressurizing the ink using a piezoelectric element or the like may also be employed.

[0040] The printing element board is provided with a plurality of sub-heaters 105. The sub-heater 105 is an element for controlling the temperature of the printing element board 101 and the ink, and specifically is a heat generating element for temperature adjustment for heating or maintaining the temperature. The sub-heater driver 108 is connected to the sub-heater 105 and performs ON / OFF control (control from ON to OFF or from OFF to ON) of the current to be caused to flow into the sub-heater 105. Note that the detailed configuration around the sub-heater 105 of the present embodiment will be described later by using 7A to 7F Give a description.

[0041] The wiring between the data processing circuit 110 and the auxiliary heater driver 108 is routed as the data processing circuit-auxiliary heater driver connection wiring 111. The "auxiliary heater control signal" as a signal for driving the plurality of auxiliary heaters 105 respectively is stored in the data processing circuit 110. The auxiliary heater control signals of this example are specifically SH_A1 to SH_A5 for array A, SH_B1 to SH_B5 for array B, SH_C1 to SH_C5 for array C, and SH_D1 to SH_D5 for array D. The auxiliary heater control signals SH_A1 to SH_D5 are each transmitted to the corresponding auxiliary heater driver at the desired timing. As shown in the figure, the wiring between the data processing circuit 110 and the plurality of auxiliary heater drivers 108 are all separate wirings.

[0042] In the present embodiment, two data processing circuits 110 are provided between the array of PAD 102 and the printing element array (specifically, array A) so that the printing element board 101 has two wiring systems. This configuration makes the individual wiring layout area of ​​each sub-heater substantially about half in size, and improves the wiring layout. In addition, since the wiring length can be shortened, the risk of malfunction due to noise is also reduced. In addition, although the case where the printing element board 101 has two systems of data processing circuits 110 is shown in this example, the number of systems of the data processing circuit 110 is not limited to two, and it is only necessary to provide at least two or more systems of the data processing circuit.

[0043] Figure 4 is a diagram of a circuit for driving the sub-heater 105 and shows Figure 3 The corresponding circuit configuration. Figure 4 , PAD 102a is the +power PAD, and PAD 102b is the GND PAD.

[0044] like Figure 6 As shown in , the wiring layer of the printing element board of this embodiment has a four-layer structure consisting of four layers of aluminum (hereinafter referred to as Al). Note that in this specification, with respect to these four layers, the bottom layer is referred to as the first layer, the middle layers are referred to as the second layer and the third layer from below, and the top layer is referred to as the fourth layer.

[0045] The fourth layer 203a as the uppermost layer is provided with GND wiring of the heater 103 and the sub-heater 105. The third layer 203b as the middle layer closer to the uppermost layer is provided with + power wiring of the heater 103 and the sub-heater 105.

[0046] The second layer 203c as the middle layer closer to the bottom layer and the first layer 203d as the bottom layer are provided with logic wiring. This logic wiring is used for the aforementioned data processing circuit-sub-heater driver connection wiring 111, etc. The printing element board of this embodiment has the following configuration: in this configuration, power is supplied from the + power supply PAD to the sub-heater via the + power supply wiring of the third layer 203b, and flows to the PAD 102b as the GND PAD via the GND wiring of the fourth layer 203a. Note that these power supply PADs can also be used as power supply PADs for the heater 103 for ejecting ink droplets.

[0047] The sub-heater driver 108 controlled by the sub-heater control signals SH_A1 to SH_D5 drives the sub-heaters. This heats any one of the heating areas 107 provided at 20 positions within the printing element board 101. Note that in the case where it is desired to heat the sub-heater at a higher temperature than in the present example ( Figure 3) In the case of controlling the temperature inside the printing element board with high precision, 20 or more heating zones may be provided. Figure 3 As shown in FIG. 1 , in the case of focusing on a certain heater array (any one of arrays A to D), a plurality of ink supply ports 106 are arranged along the extension direction of the heater array to form a supply port array, and two supply port arrays are formed in a manner of sandwiching the heater array. In addition, the sub-heater driver 108 is arranged further outside of the two arrays of ink supply ports in the left-right direction in the figure relative to the ink supply port 106. Note that the sub-heater control signals SH_A1 to SH_D5 may be directly supplied from the PAD 102 or may be generated by converting a data signal in the printing element board 101.

[0048] Focusing on any one heating area, two supply port arrays are provided for each of the printing element arrays, and the sub-heater driver 108 is disposed in an area on the opposite side of the printing element array relative to a relatively close supply port array among the two supply port arrays in the X direction.

[0049] here, Figure 5 FIG. 2 is a block diagram showing a case where a sub-heater control signal is generated in a printing element board. Figure 5 In the case of the method, if the control signal data is sent to the data processing circuit 110 via the PAD 102 simultaneously with the image data, the sub-heater control signal is generated in the data processing circuit 110 based on the control signal data. In this way, Figure 5 The method makes it possible to control the sub-heater without particularly increasing the number of PADs 102 for supplying sub-heater control signals.

[0050] exist Figure 3 In the figure, a plurality of sub-heaters 105 are arranged side by side in the direction of the longer side of the chip (the Y direction in the figure), and the sub-heaters 105 are arranged between the ink supply port 106 and the heater 103 in the X direction orthogonal to the Y direction. Since this arrangement allows the ink near the heater 103 to be heated, the ink to be ejected can be heated more efficiently than when the sub-heaters 105 are not provided. The layout of the sub-heaters of the plurality of heating areas 107 in the printing element board is basically the same, and all of them are basically the same. The number of heaters 103 respectively included in the plurality of heating areas 107 is equal. Therefore, basically, the heat generated by the sub-heaters in each area is equal, so that temperature control can be performed to make the temperature distribution in the printing element board 101 uniform. However, in the case where the heat generated by the sub-heaters is changed for each area in consideration of the possibility of temperature difference at the end of the printing element board, etc., the layout of the sub-heaters can be adjusted to adjust the temperature for each area.

[0051] 7A to 7F 1 is a diagram showing the configuration of the sub-heater 105 in this embodiment. Specifically, Fig. 7A is a top view of the secondary heater, and FIG. 7B to FIG. 7F is a cross-sectional view of a sub-heater. Note that although polycrystalline silicon (described as Poly-Si) is used as the sub-heater material here, the sub-heater material is not limited to polycrystalline silicon.

[0052] exist Fig. 7A In the embodiment, the sub-heater 105 of the heating area 107 is provided with heat generating units 209 at five locations and bypass units 208 at four locations. This bypass unit 208 is provided with Al wiring 203 and plug 206, as shown in FIG. Figure 7B . The resistance value of the bypass unit 208 is sufficiently small, such as 1 / 100 to 1 / 1000 times the resistance value of the sub-heater 105, and is estimated to be 0 ohm in this example. Note that the bypass unit 208 may be formed of at least one of aluminum (Al), copper (Cu), gold (Au), nickel (Ni), tungsten (W), titanium (Ti), or a compound thereof.

[0053] The plug 206 may be formed of, for example, tungsten (W). By connecting the Al wiring 203 having a relatively low resistance to the Poly-Si wiring of the sub-heater 105, the current flowing through the heating region 107 alternately flows through the heat generating unit 209 and the bypass unit 208, as shown in FIG. Figure 7B Since most of the current flows through the portion of the sub-heater 105 located between the adjacent Al wirings 203, this portion serves as a heat generating unit 209 to generate heat. In this way, the Al wiring 203 is connected to both ends of any one of the heat generating units 209 and is connected in parallel to the portion of the sub-heater 105 other than the heat generating unit. The above configuration allows the current to flow through the Al wiring 203 via the plug 206 on the way of the current flowing through this sub-heater 105 when the sub-heater 105 is energized in the heating area 107.

[0054] Since the sub-heater 105 in the present embodiment has a configuration in which the heat generating units 209 to generate heat are arranged to be dispersed with respect to the heating region 107, it can be said that the heating region 107 cannot be heated uniformly. However, since the heat generating units 209 and the heat generating units 209 adjacent to each other are connected by the bypass unit 208 formed of metal and having low thermal resistance, this causes the heat generated by the heat generating units 209 to diffuse via the bypass unit 208, so that the heating region 107 is heated uniformly.

[0055] Note that, in the case where it is desired that the heating area 107 be heated more uniformly, the area can be increased by shortening the length of each bypass unit 208 while maintaining the ratio between the length and the width of each heat generating unit 209. However, in this case, the effect of reducing the area of ​​the circuit or board (shrinking effect) is reduced.

[0056] In contrast, in the case where the length and width of each heat generating unit 209 are reduced and the length of the bypass unit 208 is increased, a high shrinking effect can be obtained. However, in this case, since the density of the current flowing through the wiring increases, there is a possibility of disconnection due to electromigration or the like. "Electromigration" refers to a phenomenon in which metal atoms are moved by causing current to flow through the metal wiring inside the integrated circuit. In aluminum wiring, aluminum atoms move in the direction of the flow of electrons, so that voids are generated on the cathode side to cause an open circuit failure, and on the anode side, hillocks or whiskers grow, eventually causing a short circuit failure.

[0057] Figure 7C An example of a disconnection due to electromigration is shown. Since the current is concentrated in the plug 206, electromigration is relatively easy to occur in the contact portion of the plug 206 and the Al wiring 203. Generally, the circuit is designed to have a current range that does not cause such a fault, and measures such as inserting a barrier metal between the Al wiring 203 and the plug 206 are also taken. In the present embodiment, even if a disconnection occurs in the Al wiring 203, the current is bypassed to the Poly-Si wiring of the sub-heater 105, so that the sub-heating function is not lost because the sub-heater 105 is routed across the range of the heating area 107. Such a wiring method makes it possible to obtain high reliability of the sub-heating drive. However, in the event of a disconnection, the resistance increases, so that the heat generated is reduced. Therefore, in the event of a disconnection, it is desirable to suppress the drive of the sub-heater in the area where the disconnection occurs as much as possible.

[0058] As indicated by the current path of arrow 212, since the resistance of the sub-heater 105 is high, the current tends to flow through the Al wiring 203 having a lower resistance. Figure 7B As shown in , even if two arrays of plugs 206 are provided at the Al wiring 203 at the end, current flows into the plug on the front side when viewed from the heat generating unit 209. However, with respect to the ports for obtaining power at both ends of the auxiliary heater, in the event of a disconnection, the auxiliary heating function is lost. For this reason, two or more arrays of plugs 206 are provided so as to allow current to flow via the plug on the rear side even if a disconnection has occurred on the front side. Such a configuration makes it possible to prevent complete disconnection at both ends of the auxiliary heater. Note that the same effect can be obtained in the Al wiring 203, and two or more arrays of the Al wiring 203 can be deployed instead of the plug 206 (or together with the plug 206).

[0059] exist Fig.7D In the example, the length of the Al wiring is Figure 7B As indicated by the arrow in the figure, it becomes possible to adjust the amount of heat to be generated simply by changing the position of the plug. For example, in the case where the plug 206 is deployed closer to the end of the Al wiring 203 (i.e., in the case where the plug 206 is deployed on the outside), the length of the heat generating unit is shortened, so that the resistance is reduced, and the amount of heat to be generated can be adjusted to increase. On the other hand, in the case where the plug is deployed away from the end of the Al wiring 203 (i.e., in the case where the plug is deployed on the inside), the resistance value is increased, so that the amount of heat to be generated can be adjusted to decrease. In the case where the plug 206 is deployed closer to the end of the Al wiring 203 (i.e., in the case where the plug is deployed on the inside), the resistance value is increased, so that the amount of heat to be generated can be adjusted to decrease. Fig.7D In the case of the configuration, since the design can be changed by using only one mask, it becomes possible to reduce the cost in the case of changing the amount of heat to be generated in the sub-heater.

[0060] Fig. 7E A configuration is shown in which the Poly-Si wiring of the sub-heater is intentionally cut in the bypass unit. In this configuration, although the advantages of the bypass mentioned above cannot be obtained, the degree of freedom of layout increases.

[0061] Figure 7F The cross section of the sub-heater in the aforementioned Al four-layer structure is shown. When the sub-heater 105 is driven, current flows in via the Al wiring provided in the third layer 203b, flows through the heating area 107, and finally the current flows out via the Al wiring provided in the fourth layer 203a which is the uppermost layer.

[0062] Fig. 8A yes Figure 3 FIG. 1 is an enlarged plan view of the vicinity of the heater 103 in the printing element board 101 shown in FIG. Fig. 8A In the figure, the sub-heater driver 108 is omitted for simplicity.

[0063] like Fig. 8A As shown in the figure, the ink flow channels corresponding to the heater 103 and the ink supply port 106 are separated by the nozzle material, and one ink supply port 106 is provided for each of the two heaters 103 on the left and right sides in the figure. This configuration allows ink refilling after ink ejection from the ink supply ports 106 on both sides, so that the ejection frequency can be increased and the printing throughput can be improved. In addition, in the present embodiment, since the width of the sub-heater can be reduced without reducing the amount of heat generated as mentioned above, disposing the sub-heater 105 between the heater 103 and the ink supply port 106 does not affect the ejection frequency.

[0064] Figure 8B It is along Fig. 8A A cross-sectional view taken along the cross-sectional line AA' of FIG. 1 (a view obtained by cutting the heater 103 in the direction of the ink flow channel). Figure 8C It is along Fig. 8A A cross-sectional view taken along the cross-sectional line BB' of FIG. 1 (a view obtained by cutting the sub-heater 105 in the longitudinal direction).

[0065] exist Figures 8A to 8C In the example shown in , the sub-heater 105 is provided with a bypass unit 208 and a heat generating unit 209. Figure 8B As shown in FIG. 1 , the sub-heater 105 is provided at the bottom layer using polysilicon wiring. Figure 8B and Figure 8C As shown in FIG. 2 , the Al wiring 203 has four layers, and the heater layer is stacked thereon. Then, these wirings are connected by plugs 206 and covered with an insulating layer 202. The nozzle material is stacked on the upper layer, and an ink flow channel 207 and a jet outlet 205 are formed. Note that, although the Al wiring 203 bypasses the fourth layer in this example, the Al wiring 203 may bypass the layers other than the fourth layer.

[0066] like Figure 8B As shown in , the sub-heater 105 is separated from the heater 103 by which the ink is ejected, but the position where the sub-heating is performed is ideally closer to the heater 103 from which the ink is ejected. In view of this, the present embodiment has the following configuration: In this configuration, the bypass unit 208 ( Figure 8C ) is provided near the heater, and is bypassed by Al wiring in the upper layer further closer to the heater 103, so that the heat generated in the heat generating unit of the sub-heater 105 is transferred to the portion closer to the heater. This configuration makes it possible to perform sub-heating at a portion closer to the ink to be ejected, so as to achieve a reduction in the viscosity of the ink by heating the ink, so that the speed of ink refilling can be increased, and the printing throughput can be further improved. In addition, this configuration makes it possible to eject ink with high viscosity, thus leading to an increase in image quality and an increase in the freedom of ink selection.

[0067] Fig.9A and Fig. 8A It is also an enlarged plan view of the vicinity of the heater 103, but shows the case where the same film as the heater 103 but not polysilicon is used as the material of the sub-heater. Fig. 9B It is along Fig.9A A cross-sectional view taken along the cross-sectional line AA' of FIG. 1 (a view obtained by cutting the heater 103 in the direction of the ink flow channel). Fig. 9C It is along Fig.9AA cross-sectional view taken along the cross-sectional line BB' of FIG. 1 (a view obtained by cutting the sub-heater 105 in the longitudinal direction).

[0068] Generally, the resistance value of the heater material of the heater 103 for ejecting ink is higher than the resistance value of polysilicon. Fig. 9C As shown in FIG. 1 , it is necessary to use polysilicon having a lower resistance value as the auxiliary heater material. Figure 8C Compared with the case of increasing the number of bypass units 208 to adjust the resistance value of the entire sub-heater 405. FIG. 8A to FIG. 8C The configuration is different. 9A to 9C The configuration of is a configuration in which the sub-heater 405 is close to the heater 103 and the heat generating unit 209 of the sub-heater 405 is disposed near the heater 103. Therefore, it can be compared FIG. 8A to FIG. 8C The configuration heats the vicinity of the ink to be ejected more and obtains a higher FIG. 8A to FIG. 8C Large temperature increase effect.

[0069] In the following, we will use Figures 10 to 13 To describe the data configuration for driving the sub-heater.

[0070] Fig.10 1 is a block diagram of a liquid ejection head including a head plate 14 and a plurality of printing element plates 101. In addition to the print data Dt, a clock signal Ck and a latch signal Lt transmitted from a control board are input to each of the plurality of printing element plates 101 through a flexible board 16. The clock signal Ck enables two or more elements to be synchronized by means of at least one of a rising edge (a transition from a low level to a high level) and a falling edge (a transition from a high level to a low level) of this signal waveform. The latch signal Lt enables each signal included in the print data Dt to be latched in a latch circuit not shown by means of a rising edge or a falling edge of this signal waveform. Note that although Fig.10 A line head configuration is shown, but it goes without saying that the liquid ejection head of this embodiment may be a serial head configuration.

[0071] Fig.11The print data Dt for one transmission and the clock signal Ck and latch signal Lt input to the printing element board 101 together with the print data Dt are shown. The print data Dt is transmitted in predetermined units by a serial transmission method, and the data for one transmission is referred to as a packet, etc. Although the details of the print data Dt will be described later, the print data Dt contains a plurality of information sections inf11, inf12, etc. (referred to as "information section inf" in the absence of special distinction between these sections), and each information section inf is configured to contain a plurality of signals. For example, it is assumed that the information section inf11 is m-bit data containing signals a(0), a(1), a(2) ..., a(m), and the information section inf12 is n-bit data containing signals b(0), b(1), b(2) ..., b(n), where m and n are each integers of 1 or greater. Note that the bit data is composed of a plurality of signals, and the value of each signal can be expressed as a bit value.

[0072] exist Fig.11 In the example of FIG. 1 , the above signals a(0) etc. are sequentially input at times t0, t1, t2, etc. according to the rising edge / falling edge of the clock signal Ck, and thereafter, the signals a(0) etc. transmitted in this way are latched at time tp when the latch signal Lt forms a rising edge. As described above, the print data Dt for one transmission is defined as from the falling edge of a latch signal Lt to the rising edge of the next latch signal Lt.

[0073] Fig.12 An example of the configuration of the print data Dt for one transmission is shown. The print data Dt contains a first data segment D1 and may optionally contain a second data segment D2. The data segment D1 is configured to contain a plurality of information segments inf11 to inf15, and it is assumed that the data length (data size) of the data segment D1 is fixed. On the other hand, the data segment D2 is configured to be able to contain a plurality of additional information segments inf21 to inf28, and it is assumed that the data length of the data segment D2 is variable.

[0074] First, the data sector D1 will be described.

[0075] The information field inf11 forms one aspect of the header (start condition) of the print data Dt, and configures notification data indicating the start of communication.

[0076] The information segment inf12 indicates the presence or absence of each of the plurality of additional information segments inf21 to inf28 that may be included in the data segment D2. As mentioned above, the data length of the data segment D2 is variable depending on the presence or absence of each of the plurality of additional information segments inf21 to inf28.

[0077] The information section inf13 configures data for selecting which heater to drive. A row of heaters is allocated to each block of image data.

[0078] The information section inf14 is configured with definition data for defining a pulse waveform and driving timing of a signal for driving the heater.

[0079] The information section inf15 configures diagnostic data for diagnosing whether the transmission of the print data Dt has been properly performed.

[0080] Next, the data sector D2 will be described.

[0081] In the present embodiment, only the additional information section inf21 (sub-heater selection data) is specifically defined as the additional information section. For inf22 and thereafter, for example, temperature sensor selection data, test waveform selection data, ejection presence check data, etc. can be applied.

[0082] In this way, the data segment D1 contains information necessary for actually performing printing and information directly related to the printing operation itself. On the other hand, the data segment D2 contains information necessary in the preparation stage before performing printing and information indirectly related to the printing operation.

[0083] Fig.13 The content of the information segment inf12 as the designated segment of additional information is shown. In the present embodiment, the information segment inf12 is 8-bit data. The first bit indicates the presence or absence of the additional information segment inf21. The second bit indicates the presence or absence of the additional information segment inf22. Similarly, the third to eighth bits respectively indicate the presence or absence of the corresponding additional information segment inf. In the present embodiment, it is assumed that each bit takes two values, "0" or "1". "0" indicates that the corresponding additional information segment inf exists or the operation is invalid, and "1" indicates that the corresponding additional information segment inf does not exist or the operation is valid. For example, when the first bit is "0", the data segment D2 contains the additional information segment inf21. In addition, when the first bit is "1", the data segment D2 does not contain the additional information segment inf21.

[0084] As mentioned above, an increase in image quality and an increase in the functions of the printing device have been recently required, and therefore, the number of heaters and the number of sub-heaters of the printing element board 101 are increasing, and the number of data to be transmitted is also increasing. In addition, an increase in the frequency of driving the heater and an increase in the data transmission speed have been required, so that the frequency of data transmission (between LT-LT) is being shortened. For this reason, in the present embodiment, it is assumed that the print data is divided into two or more pieces, and the print data thus divided is transmitted by using two communication channels. This is one of the features of the present embodiment.

[0085] Fig.14 As the configuration of the print data in the present embodiment, a configuration in which the print data to be transmitted is divided into two pieces and the print data thus divided is transmitted through two communication channels is shown.

[0086] like Fig.14 As shown in FIG. 1 , the image data is divided for each heater array (array A to array D). Among the image data thus divided, the image data for array A configures the information segment inf13 of the first print data Dt1. 1 , and the image data for array B configures the information segment inf13 of the first print data Dt1 2 In addition, the image data for the array C configures the information segment inf13 of the second print data Dt2. 1 , and the image data for the array D configures the information segment inf13 of the second print data Dt2 2 .

[0087] In addition, the sub-heater selection data is also divided into two halves. One of the two divided halves configures the additional information segment inf21 of the first print data Dt1, and the other configures the additional information segment inf21 of the second print data Dt2. Such data configuration makes it possible to reduce the number of pieces of data contained in the print data Dt, thereby achieving an increase in the frequency of driving the heater.

[0088] Fig.15 Shows the configuration Fig.14 The additional information segment inf21 contains details of the sub-heater selection data. Fig.15 The auxiliary heater selection data shown in Figure 3 The printing element board 101 shown in FIG. Figure 3 The printing element board 101 includes 20 heating areas 107 and one system of sub-heaters is provided for each heating area 107, so the printing element board 101 includes 20 systems of sub-heaters in total. Fig.15As shown in FIG. 1 , the sub-heater control signals for the sub-heaters of 10 systems are transmitted as the sub-heater selection data 1 of Dt1. In addition, the sub-heater control signals for the sub-heaters of the remaining 10 systems are transmitted as the sub-heater selection data 2 of Dt2. Note that since the sub-heater selection data is sent in bytes, unused data frames (written as "unclear" in the figure) are generated. "1" or "0" for these allocations does not affect the operation.

[0089] Basically, a design in which the number of communication channels for transmitting the divided Dt, the number of communication channels for transmitting the divided sub-heater selection data, and the number of systems of the data processing circuit for selecting the sub-heater are set equal is considered to have good data transfer efficiency and circuit wiring layout efficiency. Therefore, as described later (see Fig.16 ), the printing element board 101 of this example is configured to include two communication channels for transmitting Dt and sub-heater selection data. However, this embodiment is not limited to this configuration. The number of communication channels may also be two or more.

[0090] Fig.16 is a diagram showing the input aspect of Dt to the printing element board 101 in the case where the sub-heaters are selectively driven.

[0091] like Fig.16 As shown in FIG. 3 , the first print data Dt1 is input from the Dt1PAD 331, and the second print data Dt2 is input from the Dt2PAD 332. In the case where the first print data Dt1 and the second print data Dt2 are input, a plurality of additional information sections inf (additional data) are input to the additional data analyzing unit 330. Note that if there is no need to particularly distinguish these print data, the first print data Dt1 and the second print data Dt2 are collectively referred to as Dt.

[0092] After the print data Dt is input, the additional data analysis unit 330 refers to the first bit of Inf12 of Dt to determine the presence or absence of the sub-heater selection data. Then, in the case where the additional data analysis unit 330 has determined that the sub-heater selection data exists, the data of the additional information section Inf21 (sub-heater selection data) is stored in the shift register of the data processing circuit 110. Thereafter, at the timing of the input LT signal, the sub-heater control signal is transmitted to the sub-heater driver 108 of the sub-heater 105.

[0093] Furthermore, a reset signal to reset the value held in the shift register (change the value to "0") can be input from the RESETPAD 333. The reset signal is used when the printing apparatus starts to be driven or when an error has occurred.

[0094] Fig.17A 1 is a diagram for explaining the effect in the case where two communication channels are deployed in the printing element board 101 . Fig.17A is a timing diagram of the signals and the print data to be transmitted, and the following paragraph (written as two communication channels) is consistent with the configuration of this embodiment (see Fig.16 ). Note that for reference, Fig.17A The timing diagram corresponding to the traditional configuration is also shown in the upper part of FIG. Fig.17A As shown in FIG, the additional information designation section of Dt1 (or Dt2) is transmitted at a constant cycle (specifically, several kHz to tens of kHz). By using this additional information designation section, the additional data analysis unit 330 determines whether the control signal of the sub-heater is transmitted to the sub-heater driver at a constant cycle.

[0095] As mentioned above, due to Fig.16 The printing element board 101 shown in includes 20 systems of sub-heaters and it is necessary to send a control signal to each sub-heater, so the print data to be transmitted has 20 bits. In addition, the sub-heater selection data is transmitted in bytes. Therefore, in the case of one communication channel, it is necessary to divide the sub-heater selection data into three and send the sub-heater selection data (sub-heater selection data (1st byte), sub-heater selection data (2nd byte) and sub-heater selection data (3rd byte)).

[0096] In contrast, in the case of using two communication channels as in the present embodiment, it is only necessary to divide the sub-heater selection data into two and send the sub-heater selection data through the corresponding communication channels (sub-heater selection data (1st byte) and sub-heater selection data (2nd byte)). Therefore, since the time period between latch signals can be shortened by one byte, this contributes to the increase in frequency.

[0097] Note that, although Fig.17A As shown in , in principle, the number of pieces of sub-heater selection data should be equal for Dt1 and Dt2, but as Fig. 17B As shown in , the number of pieces of sub-heater selection data can be made different between Dt1 and Dt2. In this example, since the printing element board 101 includes 20 systems of sub-heaters, all sub-heater selection data can be transmitted by securing a total of three bytes for Dt1 and Dt2. However, in order to achieve the effect of this embodiment, it is necessary to make the total number of pieces of data (the number of bits) equal between Dt1 and Dt2, so it is necessary to insert additional data, such as Fig. 17B as shown in .

[0098] Although the present embodiment has been described with the number of heaters and the number of sub-heaters limited, the number of heaters and the number of sub-heaters are not limited to the above-mentioned numbers.

[0099] [Other embodiments]

[0100] The embodiments of the present disclosure may also be implemented by reading out and executing computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more completely referred to as a 'non-transitory computer-readable storage medium') to perform one or more functions in the above-mentioned embodiments and / or a computer of a system or device including one or more circuits (e.g., an application-specific integrated circuit (ASIC)) for performing one or more functions in the above-mentioned embodiments, and by a computer of the system or device, for example, reading out and executing computer executable instructions from a storage medium to perform one or more functions in the above-mentioned embodiments and / or controlling one or more circuits to perform one or more functions in the above-mentioned embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors to read out and execute computer executable instructions. Computer executable instructions may be provided to the computer, for example, from a network or a storage medium. The storage medium may include, for example, a hard disk, a random access memory (RAM), a read-only memory (ROM), a storage device of a distributed computing system, an optical disk (such as a compact disk (CD), a digital versatile disk (DVD), or a Blu-ray disk (BD)) TM ), one or more of a flash memory device, a memory card, etc.

[0101] The embodiments of the present invention may also be implemented by providing software (program) for performing the functions of the above-described embodiments to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0102] The present disclosure makes it possible to provide a configuration of a printing element board capable of reducing wire resistance, improving layout, and achieving an increase in frequency compared with a conventional configuration.

[0103] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A printing element board, include: a plurality of printing elements, the plurality of printing elements being configured to eject liquid, the plurality of printing elements being arranged in a first direction to form a printing element array; a heat generating element configured to heat the liquid; a driver configured to drive the heat generating element; a data processing circuit configured to control the driver; as well as a plurality of PADs, the plurality of PADs being configured so that a signal to be transmitted to the data processing circuit is input to the plurality of PADs from the outside, the plurality of PADs being arranged in the first direction to form a PAD array, wherein The data processing circuit is provided in at least two or more systems between the printing element array and the PAD array in a second direction orthogonal to the first direction.

2. The printing element board according to claim 1, further comprising: include: A plurality of supply ports are configured to be supplied with liquid directed toward the printing element, and the plurality of supply ports are arranged in the first direction to form a supply port array.

3. The printing element board according to claim 1 or 2, wherein two of the supply port arrays are provided for each of the printing element arrays, and The two supply port arrays are provided at different positions in the second direction, respectively, with the printing element array interposed between the two supply port arrays.

4. The printing element board according to claim 3, wherein The heat generating element is provided between the printing element array and the supply port array in the second direction.

5. The printing element board according to claim 1 or 2, wherein A plurality of heat generating elements are provided, determining a heating area for each of the plurality of heat generating elements, and The plurality of heating zones have substantially the same layout.

6. The printing element board according to claim 5, wherein The numbers of printing elements respectively included in the plurality of heating areas are equal.

7. The printing element board according to claim 6, wherein The driver is provided in a one-to-one correspondence with each of the plurality of heating areas.

8. The printing element board according to claim 7, wherein Multiple drivers are provided, and Wiring between each of the plurality of drivers and the data processing circuit is an individual wiring.

9. The printing element board according to claim 1 or 2, wherein The heat generating element is formed of polysilicon.

10. The printing element board according to claim 9, wherein The heat generating element includes a heat generating unit formed of polysilicon, a bypass unit formed of aluminum, and a plug connecting the heat generating unit and the bypass unit.

11. The printing element board according to claim 10, wherein The plug is formed of tungsten.

12. The printing element board according to claim 2, wherein The driver is disposed in a region on an opposite side of the printing element array with respect to the supply port array in the second direction.

13. The printing element board according to claim 1 or 2, wherein The data processing circuit includes a first data processing circuit and a second data processing circuit.

14. The printing element board according to claim 13, further comprising: include: a first data analysis unit configured to analyze data input from a first PAD and send the data to the first data processing circuit based on the analysis, the first PAD being one of the plurality of PADs; as well as A second data analysis unit configured to analyze data input from a second PAD and transmit the data to the second data processing circuit based on the analysis, the second PAD being different from the first PAD.

15. The printing element board according to claim 14, further comprising: include: a third PAD, the third PAD being one of the plurality of PADs, the third PAD being configured such that a reset signal is input to the third PAD, wherein When the reset signal is input to the first data processing circuit, the value held in the shift register of the first data processing circuit is reset, and When the reset signal is input to the second data processing circuit, the value held in the shift register of the second data processing circuit is reset.

16. The printing element board according to claim 1 or 2, include: A plurality of printing element arrays, in The plurality of printing element arrays are provided at different positions in the second direction, respectively.

17. A printing element board, include: a printing element configured to eject a liquid; a heat generating element configured to heat the liquid; a driver configured to drive the heat generating element; a data processing circuit configured to control the driver; as well as an analyzing unit configured to determine whether a first signal for driving the heat generating element is transmitted to the heat generating element, and to cause a shift register of the data processing circuit to store the first signal based on a result of the determination, wherein The signal for driving the printing element is transmitted at a constant cycle, The analyzing unit determines whether the first signal is transmitted at the constant period, and The first signal and a second signal for driving the printing element are transmitted by using at least two or more communication channels.

18. The printing element board according to claim 17, further comprising: include: The PAD is configured such that a signal is input to the PAD from the outside.

19. The printing element board according to claim 18, wherein The number of analysis units is equal to the number of communication channels, and The number of PADs is equal to or greater than the number of communication channels.

20. The printing element board according to claim 19, wherein The data processing circuit includes a first data processing circuit and a second data processing circuit. The analyzing unit includes a first analyzing unit and a second analyzing unit, the first analyzing unit is connected to the first data processing circuit, the second analyzing unit is connected to the second data processing circuit, and The plurality of PADs include a first PAD connected to the first analyzing unit, a second PAD connected to the second analyzing unit, and a third PAD configured such that a reset signal is input to the third PAD.

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