JP3791538B2 - Thermal recording head driving IC and thermal recording head - Google Patents

Description

  The present invention mainly relates to the arrangement of signal lines and driver transistors of a thermal recording head driving IC.

A conventional thermal recording head drive IC is shown in FIG. 3 of Japanese Patent Laid-Open No. 60-172554, in which driver transistors are arranged along the two long sides of the chip, or in FIG. 3 of Japanese Patent Laid-Open No. 1-29060. As described above, the driver transistors are arranged along one side of the chip, or arranged as three sides as shown in FIG. 6 of the 1981 IEEE International Solid-State Circuits Conference on page 47 as an example of an electroluminescence driver.
JP-A 63-104852 JP 04-276636 JP 61-242159

  Increasing the number of electrodes inevitably reduces the pitch of the electrodes, making bonding difficult. Therefore, there is a limit to reducing the electrode pitch of the IC. At present, the 70 um pitch is the limit. However, if the output electrodes are arranged on one side, the chip shape is determined by the number of outputs and the electrode pitch. The horizontal dimension of a conventional IC is determined by the number of electrodes and the pitch of the electrodes. The main factors that determine the vertical dimension are as follows. 1. 1. Vertical dimension of shift register, latch circuit and strobe circuit block; The lead wiring area when the driver pitch and the output terminal pitch are different. This can be seen well in FIG. 6 on page 47 of the 1981 IEEE International Solid-State Circuits Conference as an example of an electroluminescence driver. 3. Input / output signal terminal and control signal generation circuit; 4. It is a driver transistor.

  When the driver output is arranged on one side of the long side of the semiconductor chip, dead space increases on the long side where the input / output signal terminal and the control signal generating circuit are arranged as the number of outputs increases. Therefore, as this dead space increases, the cost of the IC becomes higher.

  Further, when the driver outputs are arranged on the three long sides of the semiconductor chip, there is a problem that the wiring is increased and the chip area is increased, so that the cost is increased.

  Therefore, the present invention solves such a problem, and an object of the present invention is to increase the area while increasing the number of driver output terminals without reducing the integration efficiency in a semiconductor device having multiple electrodes. It is an object of the present invention to provide a suppressed thermal recording head driving IC.

The thermal recording head driving IC of the present invention comprises:
A shift register comprising a plurality of flip-flop circuits that sequentially shift serial data in synchronization with a clock signal;
Latch means comprising a plurality of latch circuits for converting and holding the serial data into parallel data;
Strobe means comprising a plurality of strobe circuits for controlling the output of the parallel data using a strobe signal;
Driver means comprising a plurality of driver transistors driven based on the output signal of the strobe circuit;
A plurality of output terminals for outputting the output signal of the driver transistor to the heating resistor;
A thermal recording head drive IC including:
The shift register, the latch means, and the strobe means are composed of a plurality of blocks each having the flip-flop circuit that handles 1-bit data, the latch circuit, and the strobe circuit as unit blocks,
The plurality of blocks are arranged in a horizontal row along the long side direction in the rectangular IC.
The output terminals are arranged along all four sides of the rectangular IC,
At least a part of the driver transistors is arranged to be in the same row as the output terminals arranged along the long side.

The thermal recording head of the present invention is
A plurality of the above-mentioned thermal recording head driving ICs are arranged horizontally.

  According to the configuration of the embodiment of the present invention, the connection wiring region between the driver transistor and the block composed of the flip-flop circuit for 1 bit of the shift register, the latch circuit for 1 bit, and the strobe circuit for 1 bit. The driver transistor can be arranged on the four sides of the semiconductor chip while keeping the increase small.

  As described above, according to the embodiment of the present invention, there is an effect of suppressing an increase in area while increasing the number of driver output terminals of an IC for driving a thermal recording head. Therefore, the cost of the IC chip is reduced. Since it is not necessary to narrow the bonding pitch, there is an effect that stable mounting quality can be realized. In addition, it has the effect of reducing the cost of the thermal recording head mounted with the present IC having a low chip cost.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

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

  FIG. 2 is an enlarged view of the right side of FIG.

In the embodiment of FIG. 1, there are driver output terminals from O1 to O144, 20 terminals of O1 to O10, O135 to O144 are arranged on the lower side of the IC chip, O11 and O134 are lateral sides of the semiconductor chip, and 122 terminals of O12 to O133 are Staggered arrangement on the upper side of the semiconductor chip. In the area indicated by 11, 144 patterns each having a flip-flop circuit for 1 bit, a latch circuit for 1 bit, and a strobe circuit for 1 bit as one block are arranged in a horizontal row. Three terminals arranged between them are GND terminals. In the area indicated by 12, input / output signal terminals, power supply terminals and control signal generating circuits are arranged. Reference numerals 13 and 14 denote driver transistor regions.
FIG. 3 shows a basic circuit diagram of an IC for driving a thermal recording head. Claim 1 will be described with reference to FIGS.

  The serial data input from 30 serial data input terminals SI is synchronized with the clock signal input from 31 clock signal input terminals CR, and 33 shift registers composed of 32 FFs (flip-flops) 1 to FF144. The inside is sequentially shifted. In the present invention, as shown in FIG. 2, 144 patterns 11 each having a flip-flop circuit for 1 bit, a latch circuit for 1 bit, and a strobe circuit for 1 bit as one block are arranged in a horizontal row. In this shift, when switching from FF9 to FF10 due to the switching of the aluminum wiring layer, the Q9 data output from FF9 is not connected between adjacent flip-flops, but is connected to the data indicated by arrow 21 by 1 in the adjacent FF. I'm jumping over. Subsequently, the serial data from the FF 10 to the FF 12 and the right end is U-turned by the wiring connecting the data, and is further shifted to the FF 13 where three flip-flops are skipped. Further, the output of the strobe circuit input to the driver transistor is connected to the output from the strobe circuit having a 1-bit flip-flop circuit, a 1-bit latch circuit, and a 1-bit strobe circuit as one block. That is, just because driver transistors and output terminals are arranged on the upper and lower sides of the semiconductor chip, it is not necessary to provide two stages of shift registers on the upper and lower sides. The driver output terminal pitch is 70 μm due to the electrode pitch limitation due to bonding or the like, but the block pitch is also a pattern in which the flip-flop circuit for 1 bit, the latch circuit for 1 bit, and the strobe circuit for 1 bit are made into 1 block. Since a logic transistor advantageous for miniaturization is used in terms of transistor configuration, it can be made sufficiently smaller than 70 μm. Therefore, a flip-flop circuit for 1 bit, a latch circuit for 1 bit, and a strobe circuit for 1 bit are made into one block. In the pattern 11, the gate wiring to the driver transistors on both the upper side and the lower side in one row is sufficiently possible. The gate wiring to the driver transistors on the upper side and the lower side is possible without using the present invention. However, in the present invention, the shift position of the serial data is most considered in order to reduce the variation of the wiring resistance to the driver transistor. A flip-flop in an appropriate position can be used. That is, the serial data is first taken into the FF 9 at the most suitable position for the connection 22 to the 9th bit driver transistor, and the data output from Q9 is FF10 as a flip-flop at the most suitable position for the 10th bit driver transistor connection. Next, serial data is sequentially shifted to serial data FF11 and FF12, and the serial data shifted to FF144 is then converted into parallel data in synchronization with the latch signal inputted from 34 latch input terminal LA. 35 is held in one latch circuit. Next, 37 strobe circuits comprising latch data and one or a plurality of 36 strobe signal input terminals STR input a 1-bit flip-flop circuit, 1-bit latch circuit, and 1-bit data. The strobe circuit is one block, the output of the strobe circuit from the upper or lower side of the block pattern is input to the driver transistor gate, 38 driver transistors are turned ON / OFF, and connected to the output terminal by wire bonding or face-down mounting To a heating resistor (not shown). Since such a driver IC is mounted on the thermal recording head from several chips to several tens of chips, it is required to reduce the cost of the IC, that is, to reduce the size and increase the density. Therefore, reference numerals 13 and 14 in FIG. 1 denote driver transistor regions. However, as one embodiment of the present invention, driver transistors are arranged horizontally in 1 to 10 bits and 135 to 144 bits shown in FIG. Since the input / output signal terminal, the power supply terminal, and the control signal generating circuit have a pattern size of about 100 μm in height, the driver transistors are arranged vertically with respect to the output terminal as shown in 11 bits to 134 bits shown in FIG. Then, the semiconductor chip size becomes as large as about 300 μm in the vertical direction, and the dead space can be widened.

FIG. 4 shows a schematic plan view of a conventional thermal recording head driving IC. In the conventional layout, in the case of 41 driver transistor regions and 42 output terminals of 64 bits, the electrode pitch is about 4700 μm when the electrode pitch is 70 μm. 43 block areas in which 64 patterns of 1-bit flip-flop circuits, 1-bit latch circuits, and 1-bit strobe circuits are arranged in one block are approximately 4000 μm, 44 input / output signal terminals, power supply terminals In addition, the control signal generation circuit area has a width of about 3300 μm, and as the number of output terminals increases, the dead space at both ends of the block areas 44 and 43 increases, and the chip size does not decrease.
In the present invention, when the semiconductor chip width is about 8600 μm when the electrode pitch is 70 μm, 144 patterns each including one-bit flip-flop circuit, 1-bit latch circuit, and 1-bit strobe circuit as one block are provided. When the GND terminal is inserted, the width of the semiconductor chip is almost the same, and the input / output signal terminal, power supply terminal and control signal generating circuit area is about 3300 μm wide, and the lower side driver transistor and driver output terminal area are wide on both sides. Since it is about 5000 μm, the pattern arrangement has almost no dead space. In other words, by arranging the driver transistor and output terminal on the four sides of the semiconductor chip, it was possible to arrange only the input / output signal terminal, power supply terminal and control signal generation circuit area on the lower side of the conventional dead. This is the reason why the most suitable pattern arrangement for reducing the size of the semiconductor chip without space is realized. According to the present invention, the size of the semiconductor chip can be reduced without reducing the electrode pitch. Therefore, since the electrode pitch is not reduced, the bonding can be performed stably and the mounting quality can be improved.

  FIG. 5 shows a thermal recording head module in which a plurality of IC chips according to this embodiment are arranged horizontally. Reference numeral 50 denotes a thermal recording head driving IC according to the present invention. Reference numeral 51 denotes a base of the thermal head, 52 denotes a heating resistor element, and 53 denotes a wiring from the IC chip to the resistor element. The driver output on the lower side of the IC is wired around the lower side of the IC. As can be seen from FIG. 5, the driver output signal can be connected to the resistance element without reducing the bonding pitch.

  In the present invention, 144 outputs are taken as an example, but the number of outputs is the same regardless of the number of outputs, and the number of outputs arranged on the four sides of the semiconductor chip is an optimum output with no dead space depending on the number of outputs and the electrode pitch. The number is decided. Further, in the embodiment, the output terminals O12 to O133 arranged on the upper side of the semiconductor chip are arranged in a staggered manner, but the effect is the same even in a one-row arrangement. Further, the output terminal may be an aluminum pad for wire bonding or a bump such as a gold bump for soldering down or a solder bump.

The figure showing the schematic plane of IC which is an Example of this invention. The figure showing the expansion of the right side part of FIG. The figure showing the basic circuit of IC for a thermal recording head drive. FIG. 6 is a diagram illustrating an outline of a conventional thermal recording head driving IC. The figure showing the Example of the thermal recording head module of this invention.

Explanation of symbols

10 IC chip outline 11 Area of 144 patterns in which a flip-flop circuit for 1 bit, a latch circuit for 1 bit, and a strobe circuit for 1 bit are made into one block 12 I / O signal terminal, power supply terminal, control signal generation circuit Region 13 Vertically arranged driver transistor 14 Horizontally arranged driver transistor 20 IC chip partial outline 21 Data connection wiring 22 Connection wiring to driver transistor 30 Serial data input terminal 31 Clock input terminal 32 Flip-flop circuit 33 Shift register 34 Latch input terminal 35 Latch Circuit 36 Strobe signal input terminal 37 Strobe circuit 38 Driver output 40 IC chip 41 Driver transistor 42 Driver output terminal 43 Shift register / latch circuit / strobe circuit 44 Input / output control circuit 50 Akira of the heat-sensitive recording head drive IC
51 Recording Head Base 52 Heating Resistance Element 53 Output Signal Routing Wiring

Claims (2)

A shift register comprising a plurality of flip-flop circuits that sequentially shift serial data in synchronization with a clock signal;
Latch means comprising a plurality of latch circuits for converting and holding the serial data into parallel data;
Strobe means comprising a plurality of strobe circuits for controlling the output of the parallel data using a strobe signal;
Driver means comprising a plurality of driver transistors driven based on the output signal of the strobe circuit;
A plurality of output terminals for outputting the output signal of the driver transistor to the heating resistor;
A thermal recording head drive IC including:
The shift register, the latch means, and the strobe means are composed of a plurality of blocks having the flip-flop circuit that handles data for 1 bit, the latch circuit, and the strobe circuit as unit blocks,
The plurality of blocks are arranged in a horizontal row along the long side direction in the rectangular IC.
The output terminals are arranged along all four sides of the rectangular IC,
An IC for driving a thermal recording head, wherein at least a part of the driver transistor is arranged to be in the same row as the output terminal arranged along the long side.   2. A thermal recording head comprising a plurality of the thermal recording head driving ICs according to claim 1 arranged laterally.

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