JP2008155491A - Thermal head driver, thermal head, electronic equipment, and printing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal head driver and the like which can be manufactured by a high density process by reducing a surge voltage without increasing a chip size. <P>SOLUTION: A thermal head driver to drive heating elements includes a first output driver driving a first heating element on the basis of first pixel data in synchronization with the variation timing of a strobe signal, a delay circuit outputting a delayed strobe signal in which the strobe signal is delayed, and a second output driver driving a second heating element on the basis of second pixel data in synchronization with the variation timing of the delayed strobe signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermal head driver, a thermal head, an electronic device, and a printing system.

  A thermal printer is a printer that prints on a medium using thermal energy obtained by a heating element. For example, this thermal printer may be employed as a printer for printing a receipt delivered when purchasing an article or a printer for printing an image taken with a digital camera or the like.

  FIG. 12 is an explanatory diagram of the principle of the thermal printer.

  The thermal printer includes a thermal head 900. A plurality of heating elements are arranged in the thermal head 900, and a heating element that generates heat by a thermal head driver mounted on the thermal head 900 is selected. When the thermal energy of the heating element of the thermal head 900 is transmitted to the sheet (thermal sheet or thermal paper) 910, for example, the ink on the sheet 910 is melted (melted type), or the ink is vaporized (sublimation type) to form the paper 920. Print the image.

  For example, the thermal head driver selects a heating element to generate heat for each line, prints an image for one line, and then repeatedly feeds the paper 920. In this way, one image can be printed on the paper 920.

  The heating element of the thermal head 900 is constituted by a heating resistor, and the thermal head driver selects the heating resistor and controls the current to flow through the selected heating resistor. However, the number of heating elements increases to increase the definition of the printed image, and the amount of current flowing through the heating elements tends to increase for each line. As a result, it appears as a surge voltage of the power supply voltage and generates noise. This noise causes a malfunction of the thermal head driver.

For example, Patent Document 1 discloses a technique for suppressing such a surge voltage. In Patent Document 1, when a current is passed through a heating resistor of a thermal head with a plurality of driver ICs (Integrated Circuits), a strobe signal that defines the timing of current flow is shifted and supplied to each driver IC. A control device is disclosed. Further, there is disclosed a control device that prevents a sudden voltage drop by preventing a latch signal for taking in data of the next row from being input while delaying a strobe signal.
JP 2001-301111 A

  However, in Patent Document 1, the types of strobe signals delayed in advance by a strobe delay circuit mounted in the driver IC are limited. Since the surge voltage can be reduced by reducing the amount of current flowing through the heating resistor at the same time, the surge voltage may not be sufficiently reduced with the type of strobe signal generated in advance by the strobe delay circuit in the driver IC. .

  Further, the surge voltage depends exclusively on the configuration of the thermal head, and the surge voltage may not be reduced only on the driver IC side. For example, when the number of outputs of the driver IC (the number of heating resistors) increases, the surge voltage may not be reduced with the strobe signal generated in advance by the strobe delay circuit of the driver IC. Therefore, it is desirable that the number of strobe signals delayed by the thermal head driver can be determined depending on the thermal head on which the thermal head driver is mounted.

  Further, in recent years, there has been a demand for higher definition of printed images, while there is a high demand for downsizing and cost reduction of thermal printers. Therefore, in order to reduce the size of the thermal head, it is necessary to reduce the chip size of the thermal head driver that has been made into an IC. However, if the manufacturing process of the thermal head driver is a high-density process, the withstand voltage margin decreases, and a surge voltage that has no problem in the conventional manufacturing process may exceed this withstand voltage.

  The present invention has been made in view of the technical problems as described above, and an object thereof is to reduce a surge voltage without increasing a chip size and to produce a thermal head that can be manufactured by a high-density process. To provide a driver, a thermal head, an electronic device, and a printing system.

In order to solve the above problems, the present invention
A thermal head driver for driving a heating element,
A first output driver for driving the first heating element based on the first pixel data in synchronization with the change timing of the strobe signal;
A delay circuit that outputs a delayed strobe signal obtained by delaying the strobe signal;
The present invention relates to a thermal head driver including a second output driver that drives a second heating element based on second pixel data in synchronization with the change timing of the delayed strobe signal.

The present invention also provides
A thermal head driver for driving a plurality of heating elements,
Each driver block includes a plurality of driver blocks each having an output driver for driving a heat generating element and a delay circuit for delaying a strobe signal;
A first driver block of the plurality of driver blocks is
Driving the heating element corresponding to the first driver block based on the strobe signal and the first pixel data;
A second driver block of the plurality of driver blocks is
The present invention relates to a thermal head driver that drives a heating element corresponding to the second driver block based on a delayed strobe signal obtained by delaying the strobe signal by a delay circuit and second pixel data.

The present invention also provides
A thermal head driver for driving a plurality of heating elements,
Each driver block includes a plurality of driver blocks each having an output driver for driving a heat generating element and a delay circuit for delaying a strobe signal;
Each driver block
Output the strobe signal from the adjacent driver block as it is or delay the strobe signal by a delay circuit,
A first driver block of the plurality of driver blocks is
Driving the heating element corresponding to the first driver block based on the strobe signal and the first pixel data from the adjacent driver block;
A second driver block of the plurality of driver blocks is
The present invention relates to a thermal head driver that drives a heating element corresponding to the second driver block based on a delayed strobe signal obtained by delaying a strobe signal from an adjacent driver block by a delay circuit and second pixel data.

  According to any one of the above inventions, the heating elements can be driven at different timings according to the characteristics of the thermal head on which the thermal head driver is mounted. In addition, the circuit scale of the delay circuit is very small, and a significant increase in the chip size of the thermal head driver can be suppressed. Since the surge voltage can be reduced without increasing the chip size, a thermal head driver that can be manufactured by a high-density process can be provided.

In the thermal head driver according to the present invention,
Each driver block
A flip-flop constituting a shift register in which pixel data is shifted in a given shift direction;
A latch for latching pixel data held in the flip-flop,
The output driver is
The heating element can be driven based on the output of the latch and the strobe signal or the delayed strobe signal.

In the thermal head driver according to the present invention,
The delay circuit of each driver block is
A signal line through which a strobe signal from an adjacent driver block is transmitted includes a delay element connected to its input;
The first driver block is
With the output of the delay circuit of the first driver block electrically disconnected, the signal on the signal line is supplied as a strobe signal to the adjacent driver block,
The second driver block comprises:
In a state where the signal line is electrically disconnected, the delayed strobe signal can be supplied as a strobe signal to an adjacent driver block.

  According to the present invention, it is possible to increase or decrease the number of heating elements driven at different timings without changing the chip size.

In the thermal head driver according to the present invention,
When each driver block sequentially supplies the strobe signal or the delayed strobe signal to the adjacent driver block, the first stage driver block can output the strobe signal to the adjacent driver block as it is.

  According to the present invention, the circuit scale of the thermal head driver can be further reduced.

In the thermal head driver according to the present invention,
Each driver block
The strobe signal or the delayed strobe signal can be supplied to the output driver by electrically disconnecting the output of the delay circuit or the signal line by the master slice.

  According to the present invention, it is possible to increase or decrease the number of heating elements driven at different timings without changing the chip size.

The present invention also provides
A plurality of heating resistance elements to which a given power supply voltage is supplied at one end;
The present invention relates to a thermal head including the thermal head driver according to any one of the above, wherein the output of each output driver is electrically connected to the other end of each of the plurality of heating resistance elements.

The present invention also provides
The present invention relates to a thermal head including the thermal head driver described above.

  According to any one of the above inventions, it is possible to provide a thermal head to which a thermal head driver that can reduce a surge voltage and can be manufactured by a high-density process is applied.

The present invention also provides
Any one of the above thermal head drivers;
The present invention relates to an electronic device including a paper feed means for printing a portion of a printing paper.

The present invention also provides
The thermal head described above;
The present invention relates to an electronic device including a paper feed means for printing a portion of a printing paper.

  According to any one of the above inventions, it is possible to provide an electronic device that can reduce surge voltage and prevent malfunction due to noise.

The present invention also provides
An electronic device as described above;
The present invention relates to a printing system including a control unit that supplies print data to the electronic device.

  According to the present invention, it is possible to provide a printing system that can reduce surge voltage and prevent malfunction due to noise.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. Also, not all of the configurations described below are essential constituent requirements of the present invention.

1. Thermal Head FIG. 1 shows a configuration example of a thermal head in this embodiment.

In the thermal head 10 in this embodiment, a plurality of thermal resistance elements (a heating element and a heating resistor in a broad sense) are formed on a ceramic plate 20. In FIG. 1, a plurality of thermal resistance elements are arranged at one edge of the long side of the ceramic plate 20 according to the interval of the pixels. A power supply voltage VH is supplied to one end of the plurality of thermal resistance elements. This power supply voltage is a high voltage such as 24 V or 18 V supplied from the outside of the thermal head 10 (ceramic plate 20). The thermal head 10 includes first to M-th (M is an integer of 2 or more) thermal head drivers 30 ₁ to 30 _M. The outputs of the _first to _Mth thermal head drivers 30 ₁ to 30 _M are electrically connected to the other ends of the plurality of thermal resistance elements.

Each of the _first to _M-th thermal head drivers 30 ₁ to 30 _M thermal head drivers sets the output of the output driver connected to the thermal resistance element to, for example, a ground power supply voltage, thereby supplying current to the thermal resistance element. It can flow (drive).

2. Thermal Head Driver Next, the first to Mth thermal head drivers 30 ₁ to 30 _{M in} FIG. ₁ will be described. In the following, since the configuration of each of the _first to _Mth thermal head drivers 30 ₁ to 30 _M is substantially the same, the thermal head driver in the present embodiment applied to the _first thermal head driver 301. Will be described as an example.

  The thermal head driver in the present embodiment has a plurality of output drivers, and the timing for driving the heating elements can be shifted for each output driver. That is, the thermal head driver according to the present embodiment includes a first driver block having a first output driver for driving the first heat generating element and a second driver for driving the second heat generating element among the plurality of driver blocks. And a second driver block having a plurality of output drivers. The first output driver drives the first heating element based on the first pixel data in synchronization with the change timing of the strobe signal. Furthermore, the thermal head driver includes a delay circuit that outputs a delayed strobe signal obtained by delaying the strobe signal, and the second output driver synchronizes with the change timing of the delayed strobe signal based on the second pixel data. 2 heating elements are driven. As a result, the surge voltage can be reduced according to the characteristics of the thermal head on which the thermal head driver is mounted.

  FIG. 2 shows a configuration example of the thermal head driver in the present embodiment.

The thermal head driver 100 in the present embodiment includes a plurality of driver blocks DB _{1 to} DB _N (N is an integer of 2 or more). The driver block DB _j (1 ≦ j ≦ N, j is an integer) may include an output driver OD _j , a delay circuit DL _j , a latch LT _j, and a flip-flop DFF _j .

The thermal head driver 100 receives a clock signal CLK, serial data SI, a latch signal LAT, and an inverted strobe signal XSTROBE. Pixel data is serially input as serial data SI in synchronization with the clock signal CLK. The latch signal LAT is a signal for taking pixel data for one line into the latches LT _{1 to} LT _N. The inverted strobe signal XSTROBE is a negative logic signal. For example, a positive logic strobe signal is sequentially supplied to the driver blocks DB _{1 to} DB _N.

Flip-flop _DFF 1 _{~DFF N} driver blocks _DB 1 to DB _N constitutes a shift register in which the pixel data to be input as serial data SI is shifted in the shift direction SDR. Each flip-flop constituting the shift register captures the output of the preceding flip-flop and outputs the data captured by the flip-flop in synchronization with the change timing of the clock signal CLK.

The latch LT _j latches (holds) the data fetched into the flip-flop DFF _j when the latch signal LAT is at H level, for example. The data latched in the latch LT _j is input to the output control circuit OC _j . The output control circuit OC _j generates an output control signal cnt ₁ that performs output control of the output driver OD ₁ .

The delay circuit DL _j includes a delay element including, for example, one or a plurality of buffer circuits (or inverter circuits). The strobe signal STB _j−1 from the adjacent driver block DB _j−1 is input to the input of the delay element. Then, the delay circuit DL _j generates a delayed strobe signal DSTB _j obtained by delaying the strobe signal STB _j−1 . The output control circuit OC _j, the strobe signal _{STB j-1} or delayed strobe signal DSTB _j is output as a strobe signal STB _j.

3A to 3C are explanatory diagrams of the delay circuit DL _j shown in FIG.

As shown in FIG. 3 (A), the input of the delay circuit DL _j driver block DB _j, the strobe signal _{STB j-1} from the driver block _{DB j-1} adjacent is input. Then, the delay circuit DL _j outputs a delayed strobe signal DSTB _j obtained by delaying the strobe signal STB _j−1 . At this time, in this embodiment, the thermal head driver 100 is manufactured in a state in which the signal line through which the strobe signal STB _j−1 is transmitted or the output of the delay circuit DL _j is electrically disconnected by the master slice.

That is, by changing the wiring layer, the output of the delay circuit DL _j is electrically disconnected as shown in FIG. 3B, and the output control of the strobe signal STB _j−1 is directly performed as the strobe signal STB _j. It is output to the circuit OC _j and the adjacent driver block DB _{j + 1} . Alternatively, as shown in FIG. 3C, in the state where the signal line for transmitting the strobe signal STB _j−1 is electrically disconnected, the delayed strobe signal DSTB _j is used as the strobe signal STB _j and the output control circuit OC _j Or the adjacent driver block DB _{j + 1} .

  By doing so, the thermal resistance elements can be driven at different timings according to the characteristics of the thermal head on which the thermal head driver 100 is mounted. Moreover, the circuit scale of the delay circuit is very small, and a significant increase in the chip size of the thermal head driver 100 can be suppressed. In addition, it is possible to increase or decrease the number of thermal resistance elements driven at different timings without changing the chip size.

  Returning to FIG. 2, the description will be continued.

The output driver OD _j is configured by an N-type metal oxide semiconductor (MOS) transistor (hereinafter simply referred to as a MOS transistor). The drain of this MOS transistor becomes the driver output DOj. The source of the MOS transistors constituting the output driver _OD 1 _{~OD N} driver blocks _DB 1 to DB _N, the ground power supply voltage GND is supplied. The gates of the MOS transistors constituting the output driver OD _j, the output control signal cnt _j from the output control circuit OC _j is supplied. In Figure 2, the output control signal cnt _j, between the source and the drain of the MOS transistors constituting the output driver OD _j is by electrically conductive, the driver output DOj is set to the ground power supply voltage GND.

Driver block DB _j supplies a strobe signal from the driver block _{DB j-1} as it is, or a delayed strobe signal obtained by delaying the strobe signal from the driver block _{DB j-1,} the adjacent driver block _{DB j + 1.}

The output control circuit OC _j is the strobe signal _{STB j-1,} or delayed strobe signal DSTB _j obtained by delaying the strobe signal from the driver block _{DB j-1} adjacent the pixel data (latch corresponding to the driver block DB _j Output control signal cnt _j is generated based on the pixel data latched by LT _j .

  4 and 5 are timing charts showing an operation example of the thermal head driver 100 shown in FIG.

FIG. 4 shows the timing at which the image data input as serial data SI is stored in the flip-flops DFF _{1 to} DFF _N constituting the shift register. Image data P1, P2, P3,..., PN are serially input as serial data SI in synchronization with the clock signal CLK. For example, the image data P1 corresponds to the driver output DO1 of the driver blocks DB _1, the image data P2 corresponds to the driver output DO2 driver block DB _2, ···, the image data PN is the driver output DON of the driver block DB _N It corresponds. The flip-flop DFF ₁ takes in the image data P1 of the serial data SI in synchronization with the changing point of the clock signal CLK. Flip-flop DFF ₂ captures the image data P2 of the serial data SI synchronously with the change point of the clock signal CLK. The flip-flop DFF _N takes in the image data PN of the serial data SI in synchronization with the changing point of the clock signal CLK.

FIG. 5 shows driver output timing using image data held in the latches LT _{1 to} LT _N. Although FIG. 5 shows the driver outputs DO1 and DO2, other driver outputs are the same.

When the latch signal LAT is at the H level, image data P1 that is held in the flip-flop DFF ₁ is taken into the latch LT _1. In this case, similarly the image data P2~PN held by the flip-flop _DFF 2 _{~DFF N} is taken into the latch _LT 2 to LT _N. Accordingly, the latch signal LAT, can capture image data P1~PN of one line to latch _LT 1 to LT _N.

In FIG. 2, the strobe signal STB ₀ is output as it is as the strobe signal STB ₁ . The delay circuit DL ₂ outputs the delayed strobe signal DSTB ₂ obtained by delaying the strobe signal STB _1. The delayed strobe signal DSTB ₂ is output to the adjacent driver block DB ₃ as the strobe signal STB ₂ .

Here, as shown in FIG. 2, the output driver OD ₁ of driver block DB ₁ is thermal resistance on the basis of the image data P1 held in the strobe signal STB ₁ and the latch LT _1, is connected to the driver output DO1 The element can be driven. More specifically, the image data P1 stored in the latch LT ₁ is "1", and the strobe signal STB ₁ are at H level, the output control signal cnt ₁ becomes H level, the output driver OD ₁ of the MOS transistor The drain is set to the ground power supply voltage GND. Accordingly, current flows through the thermal resistance element connected to the output driver OD _1.

On the other hand, when the image data P1 is “0” or the strobe signal STB ₁ is at L level, the output control signal cnt ₁ remains at L level and the drain and source of the MOS transistor of the output driver OD ₁ are electrically cut off. Is done. As a result, current does not flow through the thermal resistance element connected to the output driver OD _1.

As shown in FIG. 2, the output driver OD ₂ of the driver block DB ₂ is a thermal resistance element connected to the driver output DO ₂ based on the strobe signal STB ₂ and the image data P ₂ held in the latch LT _2. Can be driven. More specifically, the image data P2 held in the latch LT ₂ is "1", and the strobe signal STB ₂ is at the H level, the output control signal cnt ₂ becomes H level, the output driver OD ₂ of the MOS transistor The drain is set to the ground power supply voltage GND. Accordingly, current flows through the thermal resistance element connected to the output driver OD _2.

On the other hand, when the image data P2 is “0” or the strobe signal STB ₂ is at L level, the output control signal cnt ₂ remains at L level, and the drain and source of the MOS transistor of the output driver OD ₂ are electrically cut off. Is done. As a result, current does not flow through the thermal resistance element connected to the output driver OD _2.

Due to the delay difference between the strobe signals STB ₁ and STB ₂ , the driver outputs DO 1 and DO ₂ also have a delay difference. As a result, there is a time difference between the current I1 flowing through the thermal resistance element connected to the driver output DO1 and the current I2 flowing through the thermal resistance element connected to the driver output DO2. Although the driver outputs DO1 and DO2 have been described with reference to FIG. 5, it is possible to suppress fluctuations in the level of the power supply voltage VH and generated noise by suppressing the generated surge voltage by providing a time difference for the other driver outputs. Become.

  The surge voltage can be suppressed to a minimum by causing current to flow through the thermal resistance element at different timings of the driver outputs DO1 to DON. However, when there is a restriction on the delay time for one line, the timing of flowing the current flowing through the thermal resistance elements connected to the driver outputs DO1 to DON may be shifted at any of a plurality of timings. Even in this case, the surge voltage can be reduced.

2.1 Modifications Note that each driver block of the thermal head driver 100 is not limited to the configuration shown in FIG.

  FIG. 6 shows another configuration example of the thermal head driver in the first modification of the present embodiment. In FIG. 6, the same parts as those in FIG. Note that FIG. 6 illustrates only a portion of the configuration of the thermal head driver that is different from FIG.

In the thermal head driver 200 in the first modification, when the strobe signal STB ₀ is input and sequentially supplied to each driver block, the delay circuit DL ₁ is bypassed in the first stage driver block DB ₁ and the strobe signal STB ₀ Is directly output to the driver block DB ₂ as the strobe signal STB ₁ . That is, when each driver block sequentially supplies a strobe signal or a delayed strobe signal to adjacent driver blocks, the first stage driver block outputs the strobe signal to the adjacent driver block as it is.

By doing so, the delay time of the delay circuit DL ₁ of the driver block DB ₁ can be omitted, and the total delay time of one line of the strobe signal can be shortened as much as possible. The driver output timings of the driver blocks DB _{1 to} DB _N can be shifted from each other.

  FIG. 7 shows a configuration example of the thermal head driver in the second modification of the present embodiment. In FIG. 7, the same parts as those in FIG. Note that FIG. 7 shows only the portion of the configuration of the thermal head driver that is different from FIG.

In the thermal head driver 300 in the second modified example, when the strobe signal STB ₀ is inputted and sequentially supplied to each driver block, the strobe signal from the adjacent driver block is sent by the delay circuit every other driver block. Delay. For example, the driver blocks DB ₁ , DB ₃ , DB ₅ ,... Perform output control using the strobe signals from the adjacent driver blocks as they are, and output the strobe signals to the next driver block. Each of the driver blocks DB ₂ , DB ₄ , DB ₆ ,... Performs output control using a delayed strobe signal obtained by delaying a strobe signal from an adjacent driver block, and outputs the delayed strobe signal to the next Output to the driver block.

In this way, it can be sufficiently reduced level of surge voltage in comparison with the case where the timing of the driver output of the driver blocks DB ₁ to DB _N is simultaneously all. For example, when the delay time by the delay circuit is constant, compared to the case where the strobe signal from the adjacent driver block is delayed by the delay circuit for each driver block, from the adjacent driver block by the delay circuit for every two driver blocks. The surge voltage level (surge amount) when the strobe signal is delayed is approximately halved. Further, the total delay time of one line can be reduced to about half compared to the case where the driver output timings of the driver blocks DB _{1 to} DB _N are shifted from each other.

In FIG. 7, the delay circuit is inserted every one driver block. However, the delay circuit may be inserted every plural driver blocks. There may be a plurality of types of driver output timings of the driver blocks DB _{1 to} DB _N.

  FIG. 8 shows a configuration example of the thermal head driver in the third modification of the present embodiment. In FIG. 8, the same parts as those in FIG.

If there is no need to provide a delay circuit DL ₁ to driver block DB ₁ as described above, in the thermal head driver 400 in the third modification has a configuration in which the delay circuit DL ₁ driver block DB ₁ is omitted ing. In this way, the circuit scale of the thermal head driver 400 can be reduced.

  The thermal head 10 shown in FIG. 1 can be mounted with the thermal head driver in any of the first to third modifications.

3. Next, a printer apparatus (thermal printer) as an electronic apparatus to which the thermal head according to any of the present embodiment and any of the first to third modifications is applied, and a printing system to which the printer apparatus is applied will be described. To do.

  FIG. 9 is an explanatory diagram of the printer apparatus according to this embodiment.

  FIG. 9 is a longitudinal sectional view showing only the main part of the longitudinal section of the printer apparatus 700 in the present embodiment. The printer apparatus 700 is configured to set thermal paper as roll paper 710. The print target portion of the roll paper 710 is sent out in a paper feed direction 712 line by line by a given paper feed mechanism (paper feed means). The print target portion is guided toward the print head 720 in the housing 714. The print head 720 mounts the thermal head 10 of FIG. When the print target portion of the roll paper 710 passes between the print head 720 and the platen 722, the print head 720 performs predetermined printing on the print target portion.

  The paper feeding mechanism further feeds the print target portion in the paper feeding direction 712, the roll paper 710 is cut by the cutter 724, and the cut paper can be taken out as a receipt 730.

  In the housing 714, a paper end sensor 740 is provided in front of the print head 720, and the end of the roll paper 710 can be detected when the roll paper 710 is fed in the paper feed direction 712.

  According to the printer device in the present embodiment, surge voltage can be reduced and malfunction due to noise can be prevented.

  FIG. 10 shows a configuration example of a printing system to which the printer device 700 of FIG. 9 is applied.

  The printing system 800 in the present embodiment includes a host computer 810 (control unit in a broad sense) and a printer device 700 that issues a receipt 730 and the like. The host computer 810 includes a main body 812, a display device 814, a keyboard 816, and a mouse 818 as a pointing device.

  FIG. 11 is a block diagram showing a configuration example of the host computer 810 shown in FIG.

  In the host computer 810, a CPU (Central Processing Unit) 860 is provided with a ROM (Read Only Memory) 864 storing program data and the like via a bus line 862, and a RAM for buffering a data processing work area and print data. (Random Access Memory) 866, a communication interface 868 for transmitting print data and print commands to the printer device 700, a display controller 870 for driving and controlling the display device 814 and displaying characters corresponding to the display data, and the keyboard 816 A keyboard controller 872 for capturing a key signal corresponding to the key and a mouse controller 874 for controlling data exchange with the mouse 818 are connected. The printer device 700 also includes a communication interface 880 that receives print data and the like from the communication interface 868.

  The CPU 860 executes predetermined print processing in accordance with a program stored in the ROM 864 or the RAM 866, expands the print data to the RAM 866, and transfers the print data in the RAM 866 to the printer device 700 via the communication interface 868. Can do.

  According to the printing system of the present embodiment, surge voltage can be reduced and malfunction due to noise can be prevented.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, the delay circuit DL _j may not be in the driver block DB _j .

  In the invention according to the dependent claims of the present invention, a part of the constituent features of the dependent claims can be omitted. Moreover, the principal part of the invention according to one independent claim of the present invention may be made dependent on another independent claim.

The figure which shows the structural example of the thermal head in this embodiment. FIG. 3 is a diagram illustrating a configuration example of a thermal head driver in the present embodiment. 3A to 3C are explanatory diagrams of the delay circuit of FIG. FIG. 3 is a timing diagram of an operation example of the thermal head driver of FIG. 2. FIG. 3 is a timing diagram of an operation example of the thermal head driver of FIG. 2. The figure which shows the other structural example of the thermal head driver in a 1st modification. The figure which shows the other structural example of the thermal head driver in a 2nd modification. The figure which shows the other structural example of the thermal head driver in a 3rd modification. FIG. 3 is an explanatory diagram of a printer apparatus according to the present embodiment. FIG. 10 is a diagram illustrating a configuration example of a printing system to which the printer apparatus of FIG. 9 is applied. FIG. 11 is a block diagram of a configuration example of a host computer in FIG. 10. Explanatory drawing of the principle of a thermal printer.

Explanation of symbols

10 thermal head, 20 ceramic plate,
30 ₁ to 30 _{M first} to _M- th thermal head drivers,
100, 200, 300, 400 Thermal head driver, 700 Printer device,
710 roll paper, 712 paper feed direction, 714 housing,
720 print head, 722 platen, 724 cutter, 730 receipt,
800 printing system, 810 host computer, 812 main body,
814 display device, 816 keyboard, 818 mouse,
CLK clock signal, _DB 1 to DB _N driver block,
DFF _{1 to} DFF _N flip-flop, DL _{1 to} DL _N delay circuit,
DO1~DON driver output, DSTB ₁ ~DSTB _N delayed strobe signals,
LT _{1 to} LT _N latch, LAT latch signal, OC _{1 to} OC _N output control circuit,
OD ₁ ~OD _N output driver, _STB 0 ~STB _N strobe signals,
SI serial data

Claims (12)

A thermal head driver for driving a heating element,
A first output driver for driving the first heating element based on the first pixel data in synchronization with the change timing of the strobe signal;
A delay circuit that outputs a delayed strobe signal obtained by delaying the strobe signal;
A thermal head driver comprising: a second output driver for driving a second heat generating element based on second pixel data in synchronization with a change timing of the delayed strobe signal. A thermal head driver for driving a plurality of heating elements,
Each driver block includes a plurality of driver blocks each having an output driver for driving a heat generating element and a delay circuit for delaying a strobe signal;
A first driver block of the plurality of driver blocks is
Driving the heating element corresponding to the first driver block based on the strobe signal and the first pixel data;
A second driver block of the plurality of driver blocks is
A thermal head driver, wherein the heat generating element corresponding to the second driver block is driven based on a delayed strobe signal obtained by delaying the strobe signal by a delay circuit and second pixel data. A thermal head driver for driving a plurality of heating elements,
Each driver block includes a plurality of driver blocks each having an output driver for driving a heat generating element and a delay circuit for delaying a strobe signal;
Each driver block
Output the strobe signal from the adjacent driver block as it is or delay the strobe signal by a delay circuit,
A first driver block of the plurality of driver blocks is
Driving the heating element corresponding to the first driver block based on the strobe signal and the first pixel data from the adjacent driver block;
A second driver block of the plurality of driver blocks is
A thermal head that drives a heating element corresponding to the second driver block based on a delayed strobe signal obtained by delaying a strobe signal from an adjacent driver block by a delay circuit and second pixel data. driver. In claim 2 or 3,
Each driver block
A flip-flop constituting a shift register in which pixel data is shifted in a given shift direction;
A latch for latching pixel data held in the flip-flop,
The output driver is
A thermal head driver that drives a heating element based on an output of the latch and the strobe signal or the delayed strobe signal. In any of claims 2 to 4,
The delay circuit of each driver block is
A signal line through which a strobe signal from an adjacent driver block is transmitted includes a delay element connected to its input;
The first driver block is
With the output of the delay circuit of the first driver block electrically disconnected, the signal on the signal line is supplied as a strobe signal to the adjacent driver block,
The second driver block comprises:
A thermal head driver, wherein the delayed strobe signal is supplied to an adjacent driver block as a strobe signal in a state where the signal line is electrically disconnected. In any of claims 2 to 5,
When each driver block sequentially supplies the strobe signal or the delayed strobe signal to adjacent driver blocks, the first stage driver block outputs the strobe signal as it is to the adjacent driver block. . In claim 5 or 6,
Each driver block
The thermal head driver, wherein the output of the delay circuit or the signal line is electrically disconnected by a master slice to supply the strobe signal or the delayed strobe signal to the output driver. A plurality of heating resistance elements to which a given power supply voltage is supplied at one end;
8. A thermal head comprising: the thermal head driver according to claim 1, wherein an output of each output driver is electrically connected to the other end of each of the plurality of heating resistance elements. .   A thermal head comprising the thermal head driver according to claim 1. The thermal head driver according to any one of claims 1 to 7,
An electronic apparatus comprising: a printing target portion of printing paper; and paper feeding means. The thermal head according to claim 8 or 9,
An electronic apparatus comprising: a printing target portion of printing paper; and paper feeding means. An electronic device according to claim 10 or 11,
And a control unit that supplies print data to the electronic device.

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