JP2001026111A - Recording head and recording apparatus comprising the recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording head comprising a fuse ROM circuit, capable of fusing a fuse with a good yield while protecting a readout circuit even in the case the withstand voltage of the readout circuit is lower than a fusing threshold value. SOLUTION: A fuse 101 to be fused selectively for storing information concerning a resistance value of a heater and an ON resistance value of a transistor for driving the heater, a fuse cutting terminal 102 connected with a voltage source 107 or a current source 108 for fusing the fuse, a fuse ROM readout circuit 103 for judging whether or not the fuse is fused, a switch 109 for the changeover operation of blocking between the fuse 101 and the readout circuit 103 at the time of fusing and forming conduction at the time of reading out the information, and a switch control input terminal 110 for controlling the switch state, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head for recording on a recording medium by a recording element and a recording apparatus having the recording head, and more particularly, to a recording head having a circuit for correcting variations in recording characteristics. And a recording apparatus provided with the recording head.

[0002]

2. Description of the Related Art As an information output device in, for example, a word processor, a personal computer, a facsimile, etc., there is a printer for recording desired information such as characters and images on a sheet-like recording medium such as paper or film.

[0003] Various types of printing methods are known for printers. However, ink-jet printing is possible because non-contact printing is possible on printing media such as paper, colorization is easy, and quietness is high. In recent years, the method has attracted particular attention and has been widely used.

[0004] Among such ink jet systems,
A recording head mounted on a recording apparatus using a method in which a change in the state of ink is caused by thermal energy generated from an electrothermal conversion element such as a heater as energy used to perform ink ejection is disclosed in 5-185
As shown in Japanese Patent No. 594, an electrothermal conversion element (heater) and its driving circuit are generally formed on the same substrate by using a semiconductor process technology and manufactured.

FIG. 4 shows an example of such a recording head circuit. In FIG. 4, reference numeral 405 denotes a heater power supply;
01 is a heater, 402 is a power transistor, 409 is a switch for controlling the time for flowing current to the heater, 4
11 is a signal input terminal (HEA) for controlling the switch.
T) and 403 are latch circuits, 408 is a latch clock signal input terminal (LT), 404 is a shift register circuit,
Reference numeral 06 denotes a data signal input terminal (DATA) for inputting image data to the shift register, and reference numeral 407 denotes a clock signal input terminal (CLK) of the shift register.

In FIG. 4, the number of transistors 402 for driving a heater and the number of logic circuit blocks including a switch 409, a latch 403, and a shift register 404 are the same as the number of the heaters 401, and are arranged at the same pitch as the heaters. It is desirable.

However, due to manufacturing problems, the recording characteristics vary, for example, the resistance value of the heater 401 and the ON state of the transistor 402 for driving the heater.
The value of the resistor has some variation with respect to the set value.

Here, when the resistance value of the heater or the resistance value of the transistor for driving the heater increases,
Since the current flowing through the heater decreases and the amount of heat generated decreases,
The ink ejection amount is reduced, and in the case of color recording, the color balance is lost. At the same time, the landing speed is deteriorated due to the reduced ejection speed, and the edge shape (sharpness) of characters and figures is deteriorated, thereby affecting the recording characteristics.

Conversely, when the resistance value of the heater or the resistance value of the transistor for driving the heater decreases, the current flowing through the heater increases, the amount of heat generation increases, and the ink discharge amount increases. Since excessive heat is applied to the heater and the surroundings, the durability deteriorates.

For this reason, in order to correct the variation in the resistance value of the heater and the ON resistance of the transistor for driving the heater, a recording device measures the resistance value of the heater and the ON resistance of the transistor for driving the heater. Built-in,
A method has been proposed in which the control is performed such that the foaming energy becomes substantially constant by changing the time (pulse width) of energizing the heater or the voltage applied to the heater in accordance with the measured value.

In order to reduce the cost by omitting the resistance measuring circuit from the recording apparatus, there is also known a recording apparatus which stores a measurement result and controls a pulse width and a heater voltage according to the storage result.

In such a recording apparatus, a resistor (fuse) that can be blown by Joule heat generated by passing an electric current is arranged on a semiconductor substrate of a recording head, and before a chip is cut out from a wafer in the course of head assembly, Measure the resistance value of the heater and the ON resistance of the transistor for driving the heater,
The measurement result is stored as a digital value, and several resistors incorporated in the recording head are selectively blown according to the stored digital value to change the conduction state, and the digital value is stored. Thereafter, the recording head is assembled. . The recording head or the recording apparatus is equipped with a digital value reading circuit, which reads a stored digital value instead of measuring a resistance value during recording, and controls a pulse width and a heater voltage.

FIG. 5 shows a fuse ROM circuit for recording one-bit information used in such a recording apparatus according to a blown state of a fuse. Usually, a plurality of circuits shown in FIG. Stores bit information.

In FIG. 5, reference numeral 501 denotes a fuse which is selectively blown to store information, and is constituted by a diffusion resistor, a thick film resistor or a thin film resistor. Reference numeral 502 denotes a fuse cutting terminal for applying a voltage and a current for blowing the fuse 501 to blow the fuse, and reference numeral 503 denotes a fuse ROM read for determining whether or not the input is connected to the fuse 501 and the fuse is blown. Circuit, 504
Is a read circuit 503 when the fuse 501 is blown.
Is a pull-up resistor for inputting a Hi level to
Readout circuit 5 when fuse 501 is not blown
The resistance value is set to several tens times to several tens of thousands times the resistance value of the fuse so that the Lo level is input to 03. 505 is a power supply connected to the pull-up resistor, 507 and 508 are a voltage source (507) and a current source (508) that are connected to the 511 fuse cutting terminal 502 at the time of blowing and supply energy for blowing. One of 507 and 508 is connected at the time of fusing.

The operation at the time of fusing will be described with reference to FIG.
In FIG. 5, when either the voltage source 507 or the current source 508 is connected to the fuse cutting terminal 502, the potential of the fuse 501 rises, a current flows through the fuse 501, and the fuse 501 generates heat, resulting in fusing. In this case, the value of the power supply 505 may be any voltage according to convenience. Here, since the resistance value of the pull-up resistor 504 is larger than that of the fuse 501, almost no current flows and the pull-up resistor 5
The fuse is blown before the fuse 04.

Next, the read operation of the fuse ROM will be described with reference to FIG. Voltage source 507 and current source 508
Is not connected at the time of reading, the input voltage VIN of the fuse reading circuit 503 is obtained by the following equation.

VIN = R501 / (R501 + R504) × VDD2 (1) Here, the resistance value R501 of the fuse 501 is 6
Assume 00 Ω and 10 MΩ after fusing. Further, the resistance value R504 of the pull-up resistor 504 is set to 100 kΩ,
Is assumed to be 5V.

The read circuit is realized by a logic circuit in which a comparator, an inverter, a NAND, a NOR, etc. are combined.
If a smaller voltage is input to the readout circuit,
When a voltage higher than the Lo level indicating the non-blown state and 2.5 V is input to the readout circuit, it is determined to be the Hi level indicating the blown state.

Therefore, by substituting the above values into equation (1), V
When IN is calculated, when the fuse 501 is not blown, VIN = 0.03 V, and the read circuit determines that the Lo level indicating non-blown has been input. On the other hand, when the fuse 501 is blown, VIN = 4.95V,
The read circuit determines that the Hi level indicating the fusing has been input.

[0020]

However, in the conventional example described above, the voltage applied to the fuse cutting terminal 502 for blowing the fuse 501 is directly applied to the fuse ROM reading circuit 503.

For this reason, the voltage and current (the fusing threshold) required for fusing are determined by the fuse ROM reading circuit 5.
If the withstand voltage exceeds 03, the reliability of the read circuit 503 is reduced. Further, when the voltage applied to the fuse cutting terminal 502 falls below the fusing threshold, there is a problem that the fusing yield of the fuse 501 is reduced.

By the way, in recent years, demands for improvement in image quality and cost reduction have made finer the elements provided on the substrate of the recording head, and with this, the breakdown voltage of the elements has been decreasing year by year.

FIG. 7 is a circuit diagram of an inverter using a PMOS 701 and an NMOS 702 used as an example of the read circuit 503, and FIG. 8 is a sectional view of the inverter.

An oxide film 81 is provided between the gate 82 of the MOS 701 or 702 and the P-type or N-type semiconductor for insulation, but the oxide film 81 is considered to be safe in terms of reliability. Is generally 3 MeV / cm.
It has been. Therefore, when the thickness of the oxide film 81 is 350 °, the breakdown voltage of the MOS becomes 10.5 V, and when a voltage higher than that is applied, the life of the oxide film 81 is reduced.

Using a Poly-Si gate of MOS as a fuse material, a film thickness of 4400 °, a sheet resistance of 500 / □,
When a fuse having a constricted portion length of 14 μm and a width of 1.5 μm is formed, the fusing threshold is 11 V, and the current at this time is 18 m.
A, which is the withstand voltage of the reading circuit 503 of 10.5 V
Will be exceeded. In order to blow the fuse with a higher yield, the voltage of the voltage source 507 or the current source 508 needs to be set to a voltage obtained by adding a margin of several tens of percent to the blowing threshold, in this case, about 15V.

As described above, in the conventional configuration, it is necessary that the fusing voltage threshold (+ margin) <the voltage of the voltage source 507 or the current source 508 <the withstand voltage of the readout circuit ... (2) However, with the miniaturization of each element formed on the substrate, the withstand voltage of the readout circuit decreases, and it becomes difficult to maintain the relationship of Expression (2), and the reliability of the readout circuit decreases, There is a problem that fusing becomes impossible.

The present invention has been made in view of the above circumstances, and includes a recording head capable of reliably writing and reading information relating to recording characteristics while protecting a reading circuit, and including the recording head. To provide a recording device.

[0028]

In order to achieve the above-mentioned object, a recording head according to the present invention is a recording head which performs recording by discharging a liquid in accordance with recording data, and uses energy for discharging the liquid. An energy generating element to be generated, a driving element for driving the energy generating element, and information on a resistance value of the energy generating element and a value of an ON resistance of the driving element, a resistor indicating whether or not it is blown, An information readout circuit that reads out the information by determining whether the resistor is blown, a fusing unit that applies a current or a voltage for blowing the resistor, the resistor and the information readout circuit; Switching means for electrically disconnecting or connecting between them.

With this configuration, it is possible to prevent the voltage applied to the resistor from the fusing means from being applied to the information reading circuit when the resistor is blown, so that the withstand voltage of the information reading circuit is higher than the fusing threshold of the resistor. Even when low, the fusing voltage threshold (+ margin) while protecting the information readout circuit
The above voltage can be applied to the resistor, and the resistor is blown with a high fusing yield without deteriorating the reliability of other circuits, and writing and reading of information on recording characteristics such as the resistance value of the energy generating element can be performed. Can be done accurately.

Further, the above object is to provide a recording element, an information generating element for indicating information on recording characteristics according to a conduction state, a reading circuit for reading information on the recording characteristics from the information generating element, The present invention is also achieved by a recording head including switching means for electrically disconnecting or conducting between the element and the readout circuit.

In this case, the electrical state between the information generating element and the read circuit is switched between when the information is written by changing the conduction state of the information generating element and when the information is read from the information generating element, and when the information is read. Since a signal applied to the information generating element at the time of writing can be prevented from being applied to the reading circuit, writing and reading of information relating to recording characteristics can be performed accurately without impairing the reliability of the circuit.

Further, if the recording apparatus is provided with such a recording head and control means for controlling a signal supplied to the drive element or the recording element in accordance with the information read by the read circuit, the read information is obtained. Accordingly, the recording quality can be improved by keeping the recording characteristics constant.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 3 is an external perspective view showing an example of an ink cartridge IJC in which an ink jet recording head as one embodiment of the recording head of the present invention is configured to be separable from an ink tank. In the ink cartridge IJC, as shown in FIG. 3, the ink tank IT and the recording head IJH can be separated at the position of the boundary line K. When the ink cartridge IJC is mounted on the carriage of the recording apparatus, an electrode (not shown) for receiving an electric signal supplied from the carriage side is provided, and the electric signal drives the recording head IJH. Ink is ejected.

The electric circuit of the recording head has a configuration in which any of the circuits described below is added to the circuit of FIG. 4 described above with respect to the conventional example.

In FIG. 3, reference numeral 300 denotes an ink ejection port array. The ink tank IT is provided with a fibrous or porous ink absorber for holding ink, and the ink is held by the ink absorber.

As described above, the ink tank IT and the recording head IJH may be configured to be separable so that only the ink tank IT can be replaced when the ink runs out. And the recording head IJH may be integrally formed to constitute an ink cartridge IJC that can be replaced at the same time.

Hereinafter, an ink jet recording head according to an embodiment of the present invention will be described with reference to some embodiments.

[First Embodiment] FIG. 1 is a circuit diagram showing a configuration of a fuse ROM circuit provided for storing information on recording characteristics in a first embodiment of a recording head according to the present invention. In FIG. 1, reference numeral 101 denotes a fuse which is a resistor for storing information on a resistance value of a heater and an ON resistance value of a transistor for driving the heater as information on printing characteristics, and is selectively blown. The conductive state is changed by the diffusion resistance, the thick film resistance or the thin film resistance.
01, a fuse cutting terminal for applying a voltage or current to blow the fuse, 103 is a fuse R for determining whether the fuse is blown or not.
The OM read circuit 104 is a pull-up resistor for inputting the Hi level to the read circuit 103 when the fuse 101 is blown, and the Lo level is input to the read circuit 103 when the fuse 101 is not blown. The pull-up resistor is set to a resistance value several tens to several tens of thousands times the resistance value of the fuse.

Numeral 105 denotes a power supply connected to a pull-up resistor, and 107 and 108 denote a fuse cutting terminal 1 at the time of blowing.
02, a voltage source (107) and a current source (108) for supplying energy for fusing.
Either 07 or 108 is connected at the time of fusing. 109
Is a switch for cutting off the electrical state between the fuse 101 and the readout circuit 103 or switching between the two states of conduction, and 110 is a switch control input terminal for controlling the state of the switch. .

Next, the operation of the switch 109 will be described with reference to FIG. When the fuse is blown, the fuse cutting terminal 1
A high voltage is applied to the fuse by the voltage source 107 or the current source 108 connected to the fuse 02. At that time, switch 1
Reference numeral 09 denotes a cutoff (OFF) state in advance by an input signal from the switch control input terminal 110, thereby preventing an overvoltage from being applied to the readout circuit. On the other hand, at the time of reading, the switch 109 is turned on in advance by an input signal from the switch control input terminal 110, so that reading can be performed as in the conventional example.

As described above, according to the present embodiment,
By switching the state of the switch 109 to the cutoff state when the fuse is blown, a voltage equal to or higher than the fusing voltage threshold (+ margin) can be applied to the fuse even when the withstand voltage of the readout circuit is lower than the fusing threshold. A fuse ROM circuit having no problem in reliability and having a high fusing yield can be realized.

[Second Embodiment] FIG. 2A is a circuit diagram showing a configuration of a fuse ROM circuit according to a second embodiment of the recording head of the present invention. In the second embodiment, the switch 109 of the first embodiment is realized by a semiconductor device. In FIG. 2A, reference numeral 209 denotes a diode that operates similarly to the switch 109 in the first embodiment.

Next, the operation of the diode 209 will be described. When the fuse is blown, a high voltage is applied to the fuse by the voltage source 107 or the current source 108 connected to the fuse cutting terminal 102. At this time, if the voltage of the power supply 105 is set to 0 V, the diode 209 becomes reverse-biased, cut off, and prevents an overvoltage from being applied to the reading circuit. On the other hand, at the time of reading, the voltage source 107 and the current source 108 are not connected at the time of reading. Therefore, the diode 209 becomes forward biased, and the input voltage VIN of the fuse read circuit 103 is determined by the following equation.

VIN = R101 / (R101 + R104) × (VDD2-VD) (3) Here, R101 is a resistance value of the fuse 101, which is assumed to be 600Ω before blowing and 10MΩ after blowing. R104 is the resistance value of the pull-up resistor 104, which is assumed to be 100 kΩ. VDD2 is the voltage of the power supply 105 and is assumed to be 5V. VD is the voltage between the anode and the cathode of the diode 209, which is about 0.7V.

The read circuit can be realized by a logic circuit combining a comparator, an inverter, a NAND and a NOR.
When a voltage smaller than V is input to the readout circuit, it is determined to be Lo level (= non-blown), and when a voltage larger than 2.5 V is input to the readout circuit, it is determined to be Hi level (= blown). .

Therefore, when the fuse 101 is not blown, VIN = approximately 0.03 V is input from the equation (3), and the readout circuit determines that the Lo level is input (= non-blown). On the other hand, when the fuse 101 is blown, from equation (3), VIN = approximately 4.26 V is input, and the readout circuit determines that the Hi level is input (= fuse).

As described above, according to the present embodiment,
Since the voltage applied when the fuse is blown is cut off by the diode 209, even if the withstand voltage of the readout circuit is lower than the blowing threshold, a voltage higher than the blowing voltage threshold (+ margin) can be applied to the fuse. A fuse ROM circuit having no problem in reliability and having a high fusing yield can be realized.

[Third Embodiment] FIG. 2B is a circuit diagram showing a configuration of a fuse ROM circuit according to a third embodiment of the recording head of the present invention. The third embodiment utilizes a fact that a diode is generally manufactured using a junction of a transistor in a semiconductor circuit.

In FIG. 2B, reference numeral 219 denotes a transistor obtained by replacing the diode 209 of the second embodiment with a transistor. In the transistor 219, the NPN transistor is CB short-circuited, and the EB junction is used as a diode.

This NPN transistor can be manufactured by the same manufacturing process as the transistor 402 for driving the heater described with reference to FIG.

As described above, according to the present embodiment,
The voltage applied when the fuse is blown is the transistor 219
Therefore, even when the withstand voltage of the readout circuit is lower than the fusing threshold, a voltage higher than the fusing voltage threshold (+ margin) can be applied to the fuse, and the reliability can be improved without increasing the number of manufacturing steps. It is possible to realize a fuse ROM circuit having no problem and having a high fusing yield.

[Fourth Embodiment] FIG. 2C is a circuit diagram showing the configuration of a fuse ROM circuit according to a fourth embodiment of the recording head of the present invention. In the fourth embodiment, as in the third embodiment, the diode 209 in the second embodiment is used.
Is replaced by a transistor 229.

Transistor 2 used in the third embodiment
19 is an NPN type, but the transistor 229 of the present embodiment is a PNP type. This transistor 229
The PNP transistor is CB short-circuited, and the EB junction is used as a diode.

As described above, according to the present embodiment,
The voltage applied when the fuse is blown is the transistor 229.
Therefore, even when the withstand voltage of the readout circuit is lower than the fusing threshold, a voltage higher than the fusing voltage threshold (+ margin) can be applied to the fuse, and the reliability can be improved without increasing the number of manufacturing steps. It is possible to realize a fuse ROM circuit having no problem and having a high fusing yield.

[Fifth Embodiment] FIG. 2D is a circuit diagram showing the configuration of a fuse ROM circuit according to a fifth embodiment of the recording head of the present invention. The fifth embodiment is similar to the third and fourth embodiments in that the diode 2 of the second embodiment
Although a transistor is used in place of the transistor 09, a CB junction is used as a diode instead of the EB junction of the transistor.

In the third and fourth embodiments, the EB
Although the junction is used as a diode, the EB junction is generally a junction of those having a high impurity concentration, so that the withstand voltage of the reverse bias is slightly lower than other junctions.

In the present embodiment, in order to improve this point, P
The CB junction of the NP transistor 239 is used as a diode. This PNP transistor 239
Can be manufactured in the same manufacturing process as the transistor 402 for driving the heater described with reference to FIG.

FIG. 9 shows an NPN transistor 402 and PN
FIG. 14 is a diagram showing an example of a stacked structure of a P transistor 239.
In FIG. 9, reference numeral 901 denotes a P-type semiconductor substrate;
It becomes the transistor substrate (substrate) and the collector of the PNP transistor, and is usually grounded. 902 is P
An N- layer serving as a collector of an NPN transistor formed on a p-type semiconductor substrate 901;
N- which is the base of the PNP transistor formed above
And is manufactured in the same step as 902. 904 is N
A P layer serving as a base of the NPN transistor formed on the layer 902; 905, a P layer serving as an emitter of the PNP transistor formed on the N− layer 903;
4 is manufactured in the same process. Reference numeral 906 denotes an N + layer formed on the P layer 904 and serving as an emitter of the NPN transistor.

In FIG. 2D, due to the Miller effect of the transistor, R 101 is 1 / current gain (β) of the PNP transistor 239 as viewed from the fuse read circuit 103.
It looks doubled. Therefore, the fuse read circuit 103
Is determined by the following equation.

VIN = R101 · I + VBE = VDD2-R104 · (1 + β) · I (4) Here, R101 is a resistance value of the fuse 101, which is assumed to be 600Ω before blowing and 10MΩ after blowing. R104 is the resistance value of the pull-up resistor 104, which is assumed to be 100 kΩ. VDD2 is the voltage of the power supply 105 and 5V
Assume that I is a current flowing through R101. β is PN
The current gain of the P transistor 239, which is assumed to be 10. VBE is a base-emitter voltage of the PNP transistor and is about 0.7V.

The read circuit can be realized by a logic circuit combining a comparator, an inverter, a NAND and a NOR. When the input threshold value is 2.5 V, if a voltage smaller than 2.5 V is input to the readout circuit, it is determined to be Lo level (= non-blown), and a voltage larger than 2.5 V is set to the readout circuit. Hi when input to
Judge as level (= fusing).

Therefore, when the fuse 101 is not blown, from equation (4), VIN = about 0.7 V is input, and
The read circuit determines that the Lo level has been input (= non-blown). On the other hand, when the fuse 101 is blown,
From equation (4), VIN = approximately 4.57 V is input, and the readout circuit determines that the Hi level has been input (= fuse).

As described above, according to the present embodiment,
The voltage applied when the fuse is blown is determined by the transistor 239.
Therefore, even if the withstand voltage of the readout circuit is lower than the fusing threshold, a voltage higher than the fusing voltage threshold (+ margin) can be applied to the fuse, and the withstand voltage can be increased without increasing the number of manufacturing steps. And a fuse ROM circuit with a high fusing yield can be realized.

[Sixth Embodiment] FIG. 10A is a circuit diagram showing a configuration of a fuse ROM circuit according to a sixth embodiment of the recording head of the present invention. The sixth embodiment uses an NMOS transistor instead of the diode 209 of the second embodiment.

When a recording head is manufactured by a bipolar process, the number of manufacturing steps is large and the cost is high. For this reason, the recording head is set to CMO for the purpose of cost reduction.
Japanese Patent Application Laid-Open No. H10-34893 proposes manufacturing by the S process. In this case, instead of the transistor 402 for driving the heater shown in FIG.
The MOS transistor 602 shown in FIG.

The NMOS transistor 1109 of FIG. 10A
Has a drain connected to the fuse 101, a source connected to the readout circuit 103, and a gate connected to the power supply 405. Reference numeral 1005 denotes a gate power supply of the NMOS transistor, which is grounded when fusing, and 105 when reading.
And the same potential.

In FIG. 10A, the input voltage VIN of the fuse read circuit 103 is determined by the following equation.

VIN = (R101 + RMOS) / (R101 + RMOS + R104) .VDD2 (5) Here, R101 is a resistance value of the fuse 101, which is assumed to be 600Ω before blowing and 10MΩ after blowing. R104 is the resistance value of the pull-up resistor 104, which is assumed to be 100 kΩ. VDD2 is the voltage of the power supply 105 and is assumed to be 5V. RMOS is the ON resistance of the NMOS transistor 1009, and is assumed to be 4 kΩ.

The read circuit can be realized by a logic circuit combining a comparator, an inverter, a NAND and a NOR. Here, when the input threshold value is 2.5 V, if a voltage smaller than 2.5 V is input to the readout circuit, it is determined to be Lo level (= non-blown),
If a voltage higher than V is input to the readout circuit, it is determined to be at the Hi level (= blown).

Therefore, when the fuse 101 is not blown, from the equation (5), VIN = about 0.22 V is input, and the read circuit determines that the Lo level is input (= non-blown). On the other hand, when the fuse 101 is blown, from equation (5), VIN = approximately 4.95 V is input, and the readout circuit determines that the Hi level is input (= fuse).

At this time, the NMO on the side connected to the fuse is
LDD (Lightly Doped Dra
The in) structure is more preferable because the withstand voltage of the NMOS transistor 1109 is improved to 40 V or more.

Here, it has been described that 1005 has the same potential as 105 at the time of reading. However, any voltage may be set as long as the NMOS transistor 1109 is turned on at the time of reading.

The NMOS transistor 1109
Can be manufactured using the same manufacturing process as that of MOS transistor 602 in FIG.

As described above, according to the present embodiment,
Since the voltage applied when the fuse is blown is cut off by the NMOS transistor 1109, even if the withstand voltage of the readout circuit is lower than the blowing threshold, a voltage higher than the blowing voltage threshold (+ margin) can be applied to the fuse. In addition, the cost can be reduced without increasing the number of manufacturing steps, and a fuse ROM circuit having no problem in reliability and having a high fusing yield can be realized.

[Seventh Embodiment] FIG. 10B is a circuit diagram showing a configuration of a fuse ROM circuit according to a seventh embodiment of the recording head of the present invention. In the seventh embodiment, instead of the diode 209 of the second embodiment, an NMOS transistor that operates as a diode by short-circuiting between the source and the gate is used.

In FIG. 10B, the NMOS transistor 1009 is used as a diode with its source and gate short-circuited. A gate oxide film of a MOS transistor is generally considered to be vulnerable to electrostatic breakdown. Accordingly, since the gate of the NMOS transistor 1109 of the circuit in FIG. 10A is connected to the power supply 405, when a surge such as static electricity is applied to the power supply 405, there is a possibility of causing electrostatic breakdown. In the seventh embodiment, resistance is inserted between the gate and the power supply, so that resistance to electrostatic breakdown is improved. The operation is similar to that of the sixth embodiment.

In the seventh embodiment, even if the NMOS transistor is replaced with a PMOS transistor as in the relationship between the third embodiment and the fourth embodiment, the same operation can be performed. Needless to say, this can be achieved.

As described above, according to the present embodiment,
Since the voltage applied when the fuse is blown is cut off by the NMOS transistor 1009, even if the withstand voltage of the readout circuit is lower than the blowing threshold, a voltage higher than the blowing voltage threshold (+ margin) can be applied to the fuse. In addition, it is possible to reduce the cost without increasing the number of manufacturing steps, to improve the reliability against electrostatic breakdown, and to realize a fuse ROM circuit with a high fusing yield.

[Eighth Embodiment] FIG. 11 is a circuit diagram showing a configuration of a fuse ROM circuit according to an eighth embodiment of the recording head of the present invention. The eighth embodiment has two fuse cutting terminals. In FIG. 11, 11
11 is a first fuse cutting terminal, and 1102 is
This is a second fuse cutting terminal.

Next, the operation when the fuse is blown will be described with reference to FIG. At the time of fusing, the first fuse cutting terminal 1
The voltage source 107 or the current source 108 is connected to 111, and at the same time, the second fuse cutting terminal is grounded. As a result, a high voltage is applied to the fuse, and the fuse is blown. At that time, the switch 109 is shut off (OFF) in advance.
And no overvoltage is applied to the readout circuit.

Next, the operation at the time of reading will be described. At the time of reading, the voltage source 1 is connected to the first fuse cutting terminal 1111.
07 or the current source 108 is not connected, and the second fuse cutting terminal is not grounded. At this time, the switch 109 is turned on (ON) in advance, and reading can be performed as in the conventional example.

As described above, according to the present embodiment,
Since the voltage applied when the fuse is blown is cut off by the switch 109, even when the withstand voltage of the readout circuit is lower than the blowing threshold, a voltage higher than the blowing voltage threshold (+ margin) can be applied to the fuse. Thus, it is possible to improve the reliability and realize a fuse ROM circuit having a high fusing yield.

In the eighth embodiment, the switch 1
09 may be configured using any one of a diode, a bipolar transistor and a MOS transistor as in the second to seventh embodiments, and it is needless to say that the object of the present invention can be achieved.

In the sixth to eighth embodiments, the MOS transistor has been described as an example.
JFET (junction field effect transistor), MIS (Me
It is needless to say that the object of the present invention can be achieved even if a transistor having the same characteristics as a MOS transistor such as talInsulated Semiconductor) is used.

In the embodiment described above, the resistor of the fuse is blown by Joule heat. However, the resistor is a semiconductor element, for example, a Zener diode, and is in an insulating state before the Zener breakdown voltage is exceeded. By applying a voltage that exceeds the Zener withstand voltage,
It goes without saying that the object of the present invention can be achieved even with a configuration that transits to the conductive state.

Further, a configuration in which there are two conductors with an insulating film, for example, a gate oxide film interposed therebetween, is also conceivable. In this case 2
The two conductors are normally insulated, but the object of the present invention can be achieved even in a configuration in which the application of a high electric field causes the breakdown of the insulating film and the two conductors become conductive.

Further, although the description has been made on the assumption that the fuse resistor is manufactured by the same material and in the same process as the gate wiring film of the MOS transistor, the recording head is protected from shock waves when bubbles in the heater or ink disappear. A cavitation-resistant film to protect the recording head from corrosion by ink, or a conductive film for mounting, for example, a film for a pump, or the same material as the wiring film, and manufactured in the same process. The same effect can be obtained.

In the above embodiments, the recording head for ejecting ink using thermal energy has been described as an example, but the present invention is not limited to this.
For example, the ink may be ejected using a piezo element or the like. Further, the present invention can be applied not only to an ink jet recording head but also to, for example, a thermal head.

Further, in the above embodiments, the liquid droplets discharged from the recording head and the liquid contained in the ink tank are not limited to ink. For example, an ink tank may contain a processing liquid discharged to a recording medium in order to improve the fixability and water resistance of the recorded image or to improve the image quality.

The above-described embodiment is particularly provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection even in an ink jet recording system. This is to achieve high-density and high-definition recording by using a method in which a state change of ink is caused by energy.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding the film boiling to the electrothermal transducer arranged corresponding to the sheet or the liquid path holding the Since thermal energy is generated in the electrothermal transducer and film boiling occurs on the heat-acting surface of the recording head, bubbles in the liquid (ink) corresponding to this drive signal on a one-to-one basis can be formed. It is valid.

By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

The configuration of the recording head is not limited to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications. A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting surface is arranged in a bent region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slot is used as a discharge part of an electrothermal transducer, and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of thermal energy corresponds to a discharge part. A configuration based on 138461 may be adopted.

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length is determined by combining a plurality of recording heads as disclosed in the above-mentioned specification. This may be either a configuration satisfying the above requirements or a configuration as a single recording head formed integrally.

In addition to the cartridge type recording head in which the ink tank is provided integrally with the recording head itself described in the above embodiment, the recording head is electrically connected to the apparatus main body by being mounted on the apparatus main body. A replaceable chip-type recording head may be used, which allows easy connection and supply of ink from the apparatus main body.

In the above-described embodiment, the description is made on the assumption that the ink is a liquid. However, even if the ink solidifies at room temperature or lower, it is possible to use an ink that softens or liquefies at room temperature. Or, in the ink jet method, generally, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range.
It is sufficient that the ink is in a liquid state when the use recording signal is applied.

In addition, in order to positively prevent the temperature rise due to thermal energy as energy for changing the state of the ink from a solid state to a liquid state, the temperature is positively prevented.
Alternatively, in order to prevent evaporation of the ink, an ink which solidifies in a standing state and liquefies by heating may be used. In any case, the application of heat energy causes the ink to be liquefied by application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used.

In such a case, the ink is disclosed in JP-A-54-5
No. 6,847, or Japanese Patent Application Laid-Open No. 60-71260, in which the porous sheet is opposed to the electrothermal converter while being held as a liquid or solid substance in the concave portion or through hole of the porous sheet. It may be. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0101]

As described above, according to the present invention,
Since the voltage applied from the fusing means to the resistor during the fusing of the resistor can be prevented from being applied to the information reading circuit, the information reading circuit can be operated even when the breakdown voltage of the information reading circuit is lower than the fusing threshold of the resistor. A voltage equal to or higher than the fusing voltage threshold (+ margin) can be applied to the resistor while protecting, and the resistor is blown with good fusing yield without impairing the reliability of other circuits, and the resistance of the energy generating element is reduced. There is an effect that writing and reading of information relating to recording characteristics such as values can be performed accurately.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of a fuse ROM circuit according to a first embodiment of the present invention.

FIG. 2A is a circuit diagram showing a configuration of a fuse ROM circuit according to a second embodiment of the present invention.

FIG. 2B is a circuit diagram showing a configuration of a fuse ROM circuit according to a third embodiment of the present invention.

FIG. 2C is a circuit diagram showing a configuration of a fuse ROM circuit according to a fourth embodiment of the present invention.

FIG. 2D is a circuit diagram showing a configuration of a fuse ROM circuit according to a fifth embodiment of the present invention.

FIG. 3 is an external view illustrating a configuration of an inkjet recording head.

FIG. 4 is a circuit diagram of a general inkjet recording head.

FIG. 5 is a circuit diagram showing a configuration of a conventional fuse ROM circuit.

FIG. 6 is a circuit diagram showing an NMOS transistor for driving a heater.

FIG. 7 is a circuit diagram illustrating a configuration of a general readout circuit.

FIG. 8 is a longitudinal sectional view showing a stacked structure of a readout circuit.

FIG. 9 is a diagram illustrating a transistor structure of a fuse ROM circuit according to a fifth embodiment of the present invention.

FIG. 10A is a fuse ROM according to a sixth embodiment of the present invention.
FIG. 3 is a circuit diagram illustrating a configuration of a circuit.

FIG. 10B is a fuse ROM according to a seventh embodiment of the present invention.
FIG. 3 is a circuit diagram illustrating a configuration of a circuit.

FIG. 11 is a circuit diagram showing a configuration of a fuse ROM circuit according to an eighth embodiment of the present invention.

[Explanation of symbols]

 101, 501 Fuse 102, 502 Fuse cutting terminal 103, 503 Readout circuit 104, 504 Pull-up resistor 105, 505 Power supply 107, 507 Voltage source 108, 508 Current source 109 Switch 209 Diode 219, 239 NPN transistor 229 PNP transistor 401 Electrothermal Conversion element (heater) 402 Power transistor 403 Latch circuit 404 Shift register circuit 414 Heater power supply 413 Switch 901 P-type semiconductor substrate 902, 903 N− layer 904, 905 P layer 906 N layer 1009, 1109 NMOS transistor 1005 Gate power supply

Claims (36)

[Claims] 1. A recording head that performs recording by discharging a liquid in accordance with print data, comprising: an energy generating element that generates energy for discharging the liquid; a driving element that drives the energy generating element; A resistor indicating information on a resistance value of the energy generating element and an ON resistance value of the driving element depending on whether the resistor is blown; and determining whether the resistor is blown and reading the information. An information reading circuit; a fusing unit for applying a current or a voltage for fusing the resistor; and a switching unit for electrically interrupting or connecting between the resistor and the information reading circuit. Characteristic recording head. 2. The method according to claim 1, wherein the switching unit electrically disconnects the resistor from the information read circuit when the resistor is blown, and the information read circuit reads the information when the information read circuit reads the information. 2. The recording head according to claim 1, wherein a resistor is electrically connected to the information reading circuit. 3. The recording head according to claim 1, wherein the energy generating element, the driving element, and the resistor are provided on a same semiconductor substrate. 4. The recording head according to claim 1, wherein the switching unit includes a switch. 5. The recording head according to claim 1, wherein the switching unit includes a semiconductor switching element. 6. The recording head according to claim 5, wherein the energy generating element, the driving element, the resistor, and the semiconductor switching element are provided on a same semiconductor substrate. . 7. The recording head according to claim 5, wherein said semiconductor switching element is a diode. 8. The recording head according to claim 7, wherein the diode has an anode connected to the information reading circuit and a cathode connected to the resistor. 9. The recording head according to claim 5, wherein said semiconductor switching element is a transistor. 10. The recording head according to claim 9, wherein said semiconductor switching element is a bipolar transistor. 11. The semiconductor switching element may be a MOS.
The recording head according to claim 9, wherein the recording head is a transistor. 12. The semiconductor switching device according to claim 12, wherein the semiconductor switching device is an MIS.
The recording head according to claim 9, wherein the recording head is a transistor. 13. The semiconductor switching device according to claim 1, wherein the semiconductor switching element is a JFE.
The recording head according to claim 9, wherein T is T. 14. The recording head according to claim 9, wherein the transistor is an NPN transistor having a collector and a base connected to the information reading circuit and an emitter connected to the fuse. 15. The recording head according to claim 9, wherein the transistor is a PNP transistor having an emitter connected to the information reading circuit and a collector and a base connected to the fuse. 16. The recording head according to claim 9, wherein the transistor is a PNP transistor having an emitter connected to the information reading circuit, a base connected to the fuse, and a collector grounded. . 17. The recording head according to claim 9, wherein the transistor is an N-type transistor having a source connected to the information reading circuit and a drain connected to the fuse. 18. The recording head according to claim 9, wherein the transistor is a P-type transistor having a drain connected to the information reading circuit and a source connected to the fuse. 19. The recording head according to claim 9, wherein the semiconductor switching element is manufactured in the same process as the driving element. 20. The recording head according to claim 1, wherein the resistor comprises a thick film resistor. 21. The recording head according to claim 1, wherein the resistor is formed of a thin-film resistor. 22. The recording head according to claim 1, wherein the resistor is made of a diffusion resistor. 23. The method according to claim 1, wherein the resistor is formed of a Zener diode.
A recording head according to the item. 24. A recording head according to claim 1, wherein the information read out by the information reading circuit is:
A control unit for controlling a signal supplied to the driving element. 25. A recording element, an information generating element indicating information on a recording characteristic according to a conduction state, a reading circuit for reading the information on the recording characteristic from the information generating element, the information generating element and the reading A switching unit for electrically disconnecting or conducting between the circuit and the circuit. 26. The recording head according to claim 25, wherein the information generating element is a resistor that indicates the information according to whether or not the element is blown. 27. The recording head according to claim 26, wherein the resistor is a fuse. 28. The recording head according to claim 25, wherein the information generating element is a semiconductor element that changes to a conductive state when a voltage exceeding a withstand voltage is applied. 29. The recording head according to claim 28, wherein said semiconductor element is a Zener diode. 30. The switching means is set to the cutoff state when changing the conduction state of the information generating element, and the switching means is set to the conduction state when the information is read from the information generation element by the readout circuit. The recording head according to any one of claims 25 to 29, further comprising a signal input unit that inputs a signal of (i). 31. The recording head according to claim 25, wherein the switching unit includes a switch. 32. The recording head according to claim 25, wherein said switching means includes a semiconductor switching element. 33. The recording head according to claim 25, wherein the recording element includes an energy generating element that generates energy for discharging ink. 34. The recording head according to claim 25, wherein the recording element includes a thermal energy converter that generates thermal energy. 35. The printing apparatus according to claim 35, further comprising a driving element for driving the thermal energy converter, wherein the recording characteristic is information on a resistance value of the thermal energy converter and a resistance value of the driving element when driving. The recording head according to claim 34. 36. A recording head according to claim 25, further comprising: a control unit that controls a signal supplied to the recording element in accordance with the information read by the reading circuit. A recording device characterized by the above-mentioned.