Ink jet printhead identification circuit and method

Information

  • Patent Grant
  • 6719397
  • Patent Number
    6,719,397
  • Date Filed
    Friday, February 7, 2003
    21 years ago
  • Date Issued
    Tuesday, April 13, 2004
    20 years ago
Abstract
The present invention provides an ink jet printhead identification circuit and method. The identification circuit is constructed of a fuse and other electronic components. A plurality of circuits are arranged and integrated on the printhead of the cartridge and encoded prior to leaving the factory subjecting the identification and detection circuits to achieve its identification purpose (of identifying general information of the cartridge, such as model number, serial number, color or gray-scale setting, and best printing quality). The circuits may alternatively be encoded subsequent to leaving the factory and usage to a certain state subjecting the identification circuits to achieve its detection purpose (of detecting the current status of the cartridge, such as whether its lifespan has elapsed).
Description




FIELD OF INVENTION




The present invention provides an identification circuit, in particular one for an inkjet printhead using shift registers to transmit the inkjet printhead identification codes to a controller in order.




BACKGROUND OF INVENTION




Consumer demand for product performance increases with technology advancement. Taking inkjet printers as an example, a variety of inkjet printers meeting various printing demands have been developed while each inkjet printer may correspond to a variety of cartridges, such as black ink cartridge, color ink cartridge, and cartridges capable of providing different numbers of jetting orifices on the printhead. The inkjet printer is capable of controlling individual cartridges through different control programs in light of the model or serial number assigned to each cartridge. Due to the various types of available cartridges, in order to prevent users from mistakenly installing an improper cartridge to an inkjet printer and rendering abnormal operation of the inkjet printer, when a cartridge is installed to an inkjet printer, the inkjet printer will identify the cartridge to ensure that the cartridge is applicable to such inkjet printer. An identification circuit is included in each printhead of the cartridge to allow the inkjet printer to identify the cartridge. The identification circuit of the cartridge is only used when the cartridge is first installed to the inkjet printer and is no longer needed once the cartridge has been identified.





FIGS. 1 and 2

illustrate a conventional inkjet printer


10


and a conventional cartridge


12


, respectively. As shown in

FIG. 1

, the inkjet printer


10


includes at least one cartridge


12


installed to the inkjet printer


10


. As shown in

FIG. 2

, the cartridge


12


includes a printhead


14


and a housing


16


. The printhead


14


includes a chip


18


and a flexible print circuit board


13


. The chip


18


is formed there on with a plurality of orifices


15


. The housing


16


includes therein an ink reservoir


17


for storing ink. The printhead


14


and ink reservoir


17


communicate to one another. The ink in the ink reservoir


17


is sprayed from the orifices


15


through the printhead


14


upon heating so as to perform the prescribed printing operation.





FIGS. 3 and 4

disclose the identification circuit diagrams of a one-bit shift register


20


and a parallel in, serial out four-bit shift register


2


, respectively, as disclosed in U.S. Pat. No. 5,940,095 entitled “Ink Jet Print Head Identification Circuit with Serial Out, Dynamic Shift Registers” and assigned to Lexmark International Incorporation.




By referring to FIG. 3, in U.S. Pat. No. 5,940,095, a default logic binary code (0 or 1) is digitally encoded into the one-bit shift register


20


as being mask programmed during fabrication by:




(1) Connecting the source


24


of load transistor


22


to ground


21


and disconnecting the source


24


to voltage source


23


, or




(2) Connecting the source


24


of load transistor


22


to a voltage source


23


and disconnecting the source


24


to ground


21


.




Under condition (1), a default logic “0” encoded to the one-bit shift register


20


is read at the output line


28


when load


25


, clock one


26


, and clock two


27


are activated in sequence. On the other hand, under condition (2), a default lock “1” encoded to the one-bit shift register


20


is read at the output line


28


.





FIG. 4

is the identification circuit diagram of a parallel in, serial out, four-bit shift register


2


as illustrated in U.S. Pat. No. 5,940,095. The circuit includes four serially connected one-bit shift registers


20




a


,


20




b


,


20




c


,


20




d


as shown in FIG.


3


. The input lines of the one-bit shift registers


20




b


,


20




c


,


20




d


(the input line


29


in

FIG. 3

) are electrically connected to the output lines of the one-bit shift register


20




a


,


20




b


,


20




c


(the output line


28


in FIG.


3


), respectively. When load


25


, clock one


26


, and clock two


27


are activated in order, the default binary codes encoded to the one-bit shift registers


20




d


,


20




c


,


20




b


,


20




a


are read from the output line


28


in sequence. If the identification code of a certain model number of an inkjet printhead is 0101, and the default binary codes being sequentially read from the one-bit shift registers


20




d


,


20




c


,


20




b


,


20




a


are 0, 1, 0 and 1, the printer (or computer) identifies the model number of the inkjet printhead. Similarly, if the identification code of a color inkjet printhead is 0001 and the default binary codes being sequentially read from the one-bit shift registers


20




d


,


20




c


,


20




b


,


20




a


are 0, 0, 0 and 1, the printer (or computer) identifies the inkjet printhead is for color printing.




In U.S. Pat. No. 5,940,095, however, the one-bit shift registers


20




a


,


20




b


,


20




c


,


20




d


are each mask programmed during fabrication to produce a default binary code (0 or 1) for allowing the printer (or computer) to identify the general information related to cartridges, while failing to record the current status of the inkjet printhead that being in use after leaving the factory.




Hence, the present invention provides an identification circuit for an inkjet printer cartridge capable of recording the current status of the inkjet printhead being in use after leaving the factory.




SUMMARY OF THE INVENTION




It is, thus, an object of the present invention to provide an ink jet printhead identification circuit and method constructed of fuses and other electronic components.




It is a further object of the present invention to provide an ink jet printhead identification circuit and method being encoded prior to leaving the factory for achieving its identification purpose (of identifying such general information of the cartridge as model number, serial number, color or gray-scale setting, and printing quality, etc.).




It is yet another object of the present invention to provide an ink jet printhead identification circuit and method that is encoded subsequent to leaving the factory for achieving its identification purpose (of detecting the current status of the cartridge).











BRIEF DESCRIPTION OF DRAWINGS





FIG. 1

is a schematic view of a conventional inkjet printer;





FIG. 2

is a schematic view showing a cartridge used in

FIG. 2

;





FIG. 3

is the register circuit diagram for the one-bit shift register disclosed in U.S. Pat. No. 5,940,095;





FIG. 4

is the circuit diagram for the parallel in, serial out identification, four-bit shift register disclosed in U.S. Pat. No. 5,940,095;





FIG. 5

is a block diagram showing the inkjet printhead identification system in accordance with the present invention;





FIG. 6

is an identification circuit diagram of a parallel in, serial out, four-bit shift register in accordance with a first preferred embodiment of the present invention;





FIG. 7

is an identification circuit diagram of a parallel in, serial out, four-bit shift register in accordance with a second preferred embodiment of the present invention;





FIG. 8

is an identification circuit diagram of a parallel in, serial out, four-bit shift register in accordance with a third preferred embodiment of the present invention; and





FIG. 9

is an identification circuit diagram of a parallel in, serial out, n-bit shift register in accordance with a fourth preferred embodiment of the present invention.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




Most printers currently available on market use ink in cyan, magenta, and yellow. The consumption for respective color ink is calculated by the control circuit of the printer during printing, and recorded to assess the respective accumulative consumption of each color ink as well as the total accumulative consumption of all color ink up-to-date, since near exhaustion of any of the three color ink will render an unreliable printing quality.





FIG. 5

illustrates a block diagram of the inkjet printhead identification and detection system


30


in accordance with the present invention. The system includes a printer circuit


31


and a printhead circuit


32


. The printer circuit


31


includes a control circuit


311


and a printhead driving circuit


312


electrically connected to the control circuit


311


. The printhead circuit


32


includes a printhead array


321


, an identification circuit


322


, and a resistor


323


. The printhead driving circuit


312


is connected to the printhead array


321


via a plurality of address lines


33


. At last part of the address lines


331


in the plurality of address lines


33


are in parallel connection with the identification circuit


322


. The identification circuit


322


and resistor


323


are electrically connected to an output line


324


of the identification circuit


322


. The other end of the resistor


323


is grounded.




When the ink in the cartridge is near exhaustion and the counter (not shown) in the circuit


311


has accumulated to a preset value, the control circuit


311


will transmit a modified identification code to the identification circuit


322


, and selects the address lines corresponding to the burned fuses. The encoding procedure for burning is then activated based on condition (1) or (2) described in the following embodiments for generating a four-bit binary code (such as 1011). The four-bit binary code is then recorded on a chip (See chip


14


of

FIG. 2

) of the inkjet printhead, such that the printer is capable of detection at the output line


324


if the lifespan of the inkjet printhead has elapsed so as to ensure printing quality. Further, when any of the three color ink is near exhaustion, a signal may be generated based on the default setting to produce a four-bit binary code (such as 1011) to be recorded on the chip of the inkjet printhead, such that the printer is capable of detecting the lifespan of the cartridge has elapsed and thus prohibit the cartridge from further use.




The transistors described in the following embodiments are field effect transistor (FET), hereafter referred to as “transistor” in short.




First Preferred Embodiment





FIG. 6

illustrates an identification circuit diagram of a parallel in, serial out, four-bit shift register


40


in accordance with a first preferred embodiment of the present invention. The four-bit shift register


40


mainly comprises a first, a second, a third and a fourth one-bit shift register fuse circuits


40




a


,


40




b


,


40




c


,


40




d


in serial connection.




Taking the first one-bit shift register fuse circuit


40




a


as an example, each programming route is formed of serial connection of a first circuit set and a second circuit set, wherein the first and second circuit sets each includes parallel connection of a fuse and a corresponding transistor. Each programming route furnishes a one-bit identification code. The first circuit set of parallel connection of a first transistor


411


and a first fuse


413


, is in serial connection with the second circuit set of parallel connection of a second transistor


412


and a second fuse


414


. The electrical connection between the two circuit sets is an output line


41


of the one-bit identification code. The ends of the first and second circuit sets are electrically connected to a ground


415


and a power source


416


, respectively. The gates of the first transistor


411


and the second transistor


412


are electrically connected to a first address line (A


i


)


417


and a second address line (A


j


)


418


, respectively. The program encoded to the first one-bit shift register fuse circuit


40




a


can only be one of the following two conditions:




Condition (1): When an appropriate voltage V


dd


is applied to the power source


416


and while the first address line


417


turns on the first transistor


411


and the second address line


418


turns off the second transistor


412


, a programming route starts at the power source


416


, going through the second fuse


414


and the first transistor


411


, and ends at the ground


415


. The voltage V


dd


is sufficient to burn the second fuse


414


. As such, a low level signal equivalent to 0 may be detected at the output line


41


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


40




a


and furnishing a one-bit identification code of ‘0’.




Condition (2): When an appropriate voltage V


dd


is applied to the power source


416


and while the second address line


418


turns on the second transistor


412


and the first address line


417


turns off the first transistor


411


, a programming route starts at the power source


416


, going through the second transistor


412


and the first fuse


413


, and ends at the ground


415


. The appropriate voltage V


dd


is sufficient to burn the first fuse


413


. As such, a high level signal equivalent to 1 may be detected from the output line


41


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


40




a


and furnishing a one-bit identification code of ‘1’.




The same principle may be applied to the second, third and fourth one-bit shift register fuse circuits


40




b


,


40




c


,


40




d


based on condition (1) or (2) to complete the encoding of the second, third and fourth one-bit shift register fuse circuits


40




b


,


40




c


,


40




d


and to furnish a one-bit identification code of ‘0’ or ‘1’, respectively.




After completion of the encoding process, the first, second, third and fourth one-bit shift register fuse circuits


40




a


,


40




b


,


40




c


,


40




d


as shown in

FIG. 6

are each capable of furnishing a one-bit identification code of 0 or 1. When load


45


, clock one


46


and clock two


47


are activated in order, the four-bit shift register


40


in accordance with the first embodiment of the present invention outputs the furnished binary codes of the one-bit shift register fuse circuits


40




d


,


40




c


,


40




b


and


40




a


in sequence, at the output line


48


. As such, the printer is capable of identifying the model number, color/gray-scale setting, and resolution of cartridge, and to detect whether the lifespan of the cartridge has elapsed based on the corresponding properties of the binary codes. By encoding binary codes prior to leaving the factory, the present invention provides identification of cartridge (model number, color/gray-scale setting, and resolution, etc.). By encoding binary codes after leaving the factory, the present invention provides detection of the current status of the cartridge (whether the lifespan of the cartridge has elapsed, etc.).




Second Preferred Embodiment





FIG. 7

illustrates an identification circuit diagram of a parallel in, serial out, four-bit shift register


50


in accordance with a second preferred embodiment of the present invention. The four-bit shift register


50


mainly comprises a first, a second, a third and a fourth one-bit shift register fuse circuits


50




a


,


50




b


,


50




c


,


50




d


in serial connection.




Taking the first one-bit shift register fuse circuit


50




a


as an example, each programming route furnishes a one-bit identification code. A transistor


511


is in serial connection with a fuse


514


. The connection between the two is an output line


51


of the one-bit identification code. The other ends of the transistor


511


and fuse


514


are electrically connected to a first power source


515


and a second power source


516


, respectively. The gate of the transistor


511


is electrically connected to an address line (A


i


)


517


.




The first power source


515


has the option of being connected either to a voltage source for accessing voltage or to an address line.




The program encoded to the first one-bit shift register fuse circuit


50




a


can only be one of the following two conditions:




Condition (1): When a high voltage V


1


is applied to the first power source


515


and the second power source


516


is grounded and while the address line


517


turns on the transistor


511


, a programming route starts at the power source


515


, going through the transistor


511


and the fuse


514


, and ends at the second power source (ground)


516


. The high voltage V


1


is sufficient to burn the fuse


514


. As such, a low level signal equivalent to 0 may be detected at the output line


51


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


50




a


and furnishing a one-bit identification code of ‘0’. When a logic high voltage is applied to the second power source


516


and a low voltage is applied to the address line


517


to turn off the transistor


511


, the burned fuse


514


would prevent the logic high voltage at the second power source


516


from being read at the output line


51


. Instead, a low level signal equivalent to 0 is the first bit read by the first one-bit shift register fuse circuit


50




a.






Condition (2): By turning off the transistor


511


via the address line


517


that is connected to a low voltage such that the voltage V


I


applied to the first power source


515


cannot reach the fuse


514


, the integrity and conductivity of the fuse


514


is preserved. As such, a high level signal equivalent to 1 may be detected at the output line


51


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


50




a


and furnishing a one-bit identification code of ‘1’. As a logic high voltage is applied to the second power source


516


and a low voltage is applied to the address line


517


to turn off the transistor


511


, the logic high voltage at the second power source


516


will then pass through the fuse


514


and transmitted to the first bit of the four-bit shift register


50


via the output line


51


, such that the first bit of the four-bit shift register


50


is a high level signal equivalent to 1.




The same principle may be applied to the second, third and fourth one-bit shift register fuse circuits


50




b


,


50




c


,


50




d


based on condition (1) or (2) to complete the encoding of the second, third and fourth one-bit shift register fuse circuits


50




b


,


50




c


,


50




d


and to furnish a one-bit identification code of ‘0’ or ‘1’, respectively.




After completion of the encoding process, the first, second, third and fourth one-bit shift register fuse circuits


50




a


,


50




b


,


50




c


,


50




d


as shown in

FIG. 7

are each capable of furnishing a one-bit identification code of 0 or 1. When load


55


, clock one


56


and clock two


57


are activated in order, the four-bit shift register


50


in accordance with the second embodiment of the present invention outputs the furnished binary codes of the one-bit shift register fuse circuits


50




d


,


50




c


,


50




b


and


50




a


in sequence, at the output line


58


. As such, the printer is capable of identifying the model number, color/gray-scale setting, and resolution of cartridge, and to detect whether the lifespan of the cartridge has elapsed based on the corresponding properties of the binary codes. By encoding binary codes prior to leaving the factory, the present invention provides identification of cartridge (model number, color/gray-scale setting, and resolution, etc.). By encoding binary codes after leaving the factory, the present invention provides detection of the current status of the cartridge (whether the lifespan of the cartridge has elapsed, etc.).




Third Preferred Embodiment





FIG. 8

illustrates an identification circuit diagram of a parallel in, serial out, four-bit shift register


60


in accordance with a third preferred embodiment of the present invention. The four-bit shift register


60


is primarily formed of serial connection of a first, a second, a third and a fourth one-bit shift register fuse circuits


60




a


,


60




b


,


60




c


,


60




d.






Taking the first one-bit shift register fuse circuit


60




a


as an example, each programming route furnishes a one-bit identification code. A transistor


611


is electrically connected with a fuse


614


. The electrical connection between the two is an output line


61


of the one-bit identification code. The other end of the transistor


611


is electrically connected to ground


615


. The other end of the fuse


614


is electrically connected to a power source


616


. The gate of the transistor


611


is electrically connected to an address line (A


i


)


617


. The program encoded to the first one-bit shift register fuse circuit


50




a


can only be one of the following two conditions:




Condition (1): When an appropriate voltage is applied to the power source


616


and while the address line


617


turns on the transistor


611


, a programming route starts at the power source


616


, going through the fuse


614


and the transistor


611


, and ends at the ground


615


. The high voltage is sufficient to burn the fuse


614


. As such, a low level signal equivalent to 0 may be detected at the output line


61


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


60




a


and furnishing a one-bit identification code of ‘0’. As a logic high voltage is applied to the power source


616


and a low voltage is applied to the address line


617


to turn off the transistor


611


, the burned fuse


614


would prevent the logic high voltage at the power source


616


from being read at the output line


61


. Instead, a low level signal equivalent to 0 is the first bit read by the first one-bit shift register fuse circuit


50




a.






Condition (2): By turning off the transistor


611


via the address line


617


that is connected to a low voltage such that the voltage applied to the power source


616


cannot reach the fuse


614


, the integrity and conductivity of the fuse


614


is preserved. As such, a high level signal equivalent to 1 may be detected at the output line


61


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


60




a


and furnishing a one-bit identification code of ‘1’. As a logic high voltage is applied to the power source


616


and a low voltage is applied to the address line


617


to turn off the transistor


611


, the logic high voltage at the power source


616


will pass through the fuse


614


and then transmitted to the first bit of the four-bit shift register


60


via the output line


61


, such that the first bit of the four-bit shift register


60


is a high level signal equivalent to 1.




The same principle may be applied to the second, third and fourth one-bit shift register fuse circuits


60




b


,


60




c


,


60




d


based on condition (1) or (2) to complete the encoding of the second, third and fourth one-bit shift register fuse circuits


60




b


,


60




c


,


60




d


and to furnish a one-bit identification code of ‘0’ or ‘1’, respectively.




After completion of the encoding process, the first, second, third and fourth one-bit shift register fuse circuits


60




a


,


60




b


,


60




c


,


60




d


as shown in

FIG. 8

are each capable of furnishing a one-bit identification code of 0 or 1. When load


65


, clock one


66


and clock two


67


are activated in order, the four-bit shift register


60


in accordance with the third embodiment of the present invention outputs the furnished binary codes of the one-bit shift register fuse circuits


60




d




60




c


,


60




b


and


60




a


in sequence, at the output line


68


. As such, the printer is capable of identifying the model number, color/gray-scale setting, and resolution of cartridge, and to detect whether the lifespan of the cartridge has elapsed based on the corresponding properties of the binary codes. By encoding binary codes prior to leaving the factory, the present invention provides identification of cartridge (model number, color/gray-scale setting, and resolution, etc.). By encoding binary codes after leaving the factory, the present invention provides detection of the current status of the cartridge (whether the lifespan of the cartridge has elapsed, etc.).




Fourth Preferred Embodiment





FIG. 9

is an identification circuit diagram of a parallel in, serial out, n-bit shift register


70


in accordance with a fourth preferred embodiment of the present invention. The n-bit shift register


70


is primarily formed of serial connection of a first, a second, a third, to an n


th


one-bit shift register fuse circuits


70




a


,


70




b


,


70




c


, to


70




n.






Taking the first one-bit shift register fuse circuit


70




a


as an example, each programming route furnishes a one-bit identification code. A first transistor


711


is in serial connection with a fuse


714


. The electrical connection between the two is an output line


71


of the one-bit identification code. The other ends of the first transistor


711


and fuse


714


are electrically connected to a first power source


715


and a second power source


716


, respectively. A second transistor


712


is provided between the second power source


716


and a ground


719


. The gates of the first transistor


711


and second transistor


712


are electrically connected to a first address line (A


i


)


717


and a second address line (A


j


)


718


, respectively. The first power source


715


has the option of being connected either to a voltage source for accessing voltage or to an address line. The program encoded to the first one-bit shift register fuse circuit


70




a


can only be one of the following two conditions:




Condition (1): When an appropriate voltage is applied to the first power source


715


and while the first address line (A


i


)


717


and second address line (A


j


)


718


turn on the first transistor


711


and second transistor


712


, respectively, a programming route starts at the first power source


715


, going through the first transistor


711


, the fuse


714


, and the second transistor


712


, and ends at the ground


719


.




The appropriate voltage is sufficient to burn the fuse


714


. As such, a low level signal equivalent to 0 may be detected at the output line


71


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


70




a


and furnishing a one-bit identification code of ‘0’. As a logic high voltage is applied to the second power source


716


and a low voltage is applied to the first address line


717


and second address line


718


to turn off the transistors


711


and


712


, the burned fuse


714


would prevent the logic high voltage at the second power source


716


from being read at the output line


71


. Instead, a low level signal equivalent to 0 is the first bit read by the first one-bit shift register fuse circuit


70




a.






Condition (2): By turning off the first transistor


711


and the second transistor


712


via the first address line (A


i


)


717


and the second address line (A


j


)


718


that are connected to a low voltage, respectively, such that the voltage applied to the first power source


715


cannot reach the fuse


714


, the integrity and conductivity of the fuse


714


is preserved. As such, a high level signal equivalent to 1 may be detected at the output line


71


, as described hereinafter, for completing the encoding of the first one-bit shift register fuse circuit


70




a


and furnishing a one-bit identification code of ‘1’. As a logic high voltage is applied to the second power source


716


and a low voltage is applied to the first address line


717


and second address line


718


to turn off the first transistor


711


and second transistor


712


, respectively, the logic high voltage at the second power source


716


will pass through the fuse


714


and transmitted to the first bit of the n-bit shift register


70


via the output line


71


, such that the first bit of the n-bit shift register


70


is a high level signal equivalent to 1.




The same principle may be applied to the second, third to n


th


one-bit shift register fuse circuits


70




b


,


70




c


to


70




n


based on condition (1) or (2) to complete the encoding of the second, third to n


th


one-bit shift register fuse circuits


70




b


,


70




c


to


70




n


and to furnish a one-bit identification code of ‘0’ or ‘1’, respectively.




After completion of the encoding process, the first, second, third to n


th


one-bit shift register fuse circuits


70




a


,


70




b


,


70




c


to


70




n


as shown in

FIG. 9

are each capable of furnishing a one-bit identification code of 0 or 1. When load


75


, clock one


76


and clock two


77


are activated in order, the n-bit shift register


70


in accordance with the fourth embodiment of the present invention outputs the furnished binary codes of the one-bit shift register fuse circuits


70




n


to


70




b


and


70




a


in sequence, at the output line


78


. As such, the printer is capable of identifying the model number, color/gray-scale setting, and resolution of cartridge, and to detect whether the lifespan of the cartridge has elapsed based on the corresponding properties of the binary codes. By encoding binary codes prior to leaving the factory, the present invention provides identification of cartridge (model number, color/gray-scale setting, and resolution, etc.). By encoding binary codes after leaving the factory, the present invention provides detection of the current status of the cartridge (whether the lifespan of the cartridge has elapsed, etc.).




One advantage of this preferred embodiment is that n address lines (A


1


-A


n


) are used to encode n×(n−1)/2 fuses. For example, only five address lines (A


1


, A


2


, A


3


, A


4


, A


5


) are needed to encode 10 fuses, exemplified as follows:

























Fuse




1




2




3




4




5




6




7




8




9




10











First




A1




A1




A1




A1




A2




A2




A2




A3




A3




A4






address






line (A


1


)






Second




A2




A3




A4




A5




A3




A4




A5




A4




A5




A5






address






line (A


2


)














The parallel in, serial out shift registers


40


,


50


,


60


and


70


in accordance with the present invention as described above, may be integrated into the chip


18


of the printhead


14


shown in FIG.


2


. Shift registers consisting of different numbers of bits may also replace the four-bit shift registers


40


,


50


, and


60


. The identification purpose of the identification circuit is not limited to the identification of the model number, serial number, color or gray-scale setting, and resolution of the cartridge; neither is the identification purpose of the identification circuit limited to the detection of whether the lifespan of the cartridge has elapsed.




In summary, the conventional U.S. Pat. No. 5,940,096 can only achieve the identification purpose by encoding the cartridge prior to leaving the factory. The present invention, however, allows encoding of the cartridge prior to leaving the factory, or subsequent to leaving the factory and usage to a certain state for achieving the identification and detection purposes. Further, the conventional U.S. Pat. No. 5,940,095 digitally encodes a default logic binary code (0 or 1) into a one-bit shift register


20


as being mask programmed during fabrication, while the present invention adopts fuses to establish the default logic binary code. Hence, the technical measures as adopted by and the effects as achieved by the present invention are distinguishably different from those disclosed in the conventional U.S. Pat. No. 5,940,095.




The above embodiments are intended for describing the present invention without limiting the scope that the present invention may be applied. Modifications made in accordance with the disclosures of the present invention without departing from the spirits of the present invention are covered by the equivalents of the present invention.



Claims
  • 1. An inkjet printhead identification circuit, used in a printhead of a cartridge for identifying general information and detecting current status of the cartridge, comprising:a power source, a ground, an output line, a first address line, and a second address line; a first transistor and a first fuse in parallel connection, provided between the ground and the output line, the first transistor having a gate that is electrically connected to the first address line; and a second transistor and a second fuse in parallel connection, provided between the power source and the output line, the second transistor having a gate that is electrically connected to the second address line; wherein, when the first address line turns on the first transistor and the second address line turns off the second transistor, an appropriate voltage applied to the power source burns the second fuse; and when the second address line turns on the second transistor and the first address line turns off the first transistor, an appropriate voltage applied to the power source burns the first fuse.
  • 2. The inkjet printhead identification circuit of claim 1, wherein a plurality of identification circuits form a shift register.
  • 3. The inkjet printhead identification circuit of claim 1, wherein a plurality of identification circuits form a logical circuit.
  • 4. The inkjet printhead identification circuit of claim 1, wherein the general information is at least one of model number, serial number, color or gray-scale setting, and best printing quality.
  • 5. The inkjet printhead identification circuit of claim 1, wherein the current status of the cartridge is to ascertain a ink volume in the cartridge in lower than a preset value.
  • 6. An inkjet printing apparatus for furnishing identification information of a printhead to an inkjet printer, comprising:a control circuit, for generating control signals that control operation of the inkjet printer; an inkjet printhead performing printing operation based on the control signals generated by the control circuit; an identification circuit, used in a printhead of a cartridge for identifying general information and detecting current status of the cartridge, comprising: a power source, a ground, an output line, a first address line, and a second address line; a first transistor and a first fuse connected in parallel, provided between the ground and the output line, the first transistor having a gate that is electrically connected to the first address line; and a second transistor and a second fuse in parallel connection, provided between the power source and the output line, the second transistor having a gate that is electrically connected to the second address line; wherein, when the control circuit generates control signals commanding the first address line to turn on the first transistor and the second address line to turn off the second transistor, an appropriate voltage applied to the power source bums the second fuse; and when the control circuit generates control signals commanding the second address to turn on the second transistor and the first address line to turn off the first transistor, an appropriate voltage applied to the power source burns the first fuse.
  • 7. An inkjet printhead identification method for identifying general information of a cartridge and detecting current status of the cartridge, comprising the steps of:a. providing an identification circuit to a printhead of a cartridge, the identification circuit comprises: a power source, a ground, an output line, a first address line, and a second address line; a first transistor and a first fuse in parallel connection, provided between the ground and the output line, the first transistor having a gate that is electrically connected to the first address line; and a second transistor and a second fuse in parallel connection, provided between the power source and the output line, the second transistor having a gate that is electrically connected to the second address line; b. burning the second fuse by an appropriate voltage applied to the power source when the first address line turns on the first transistor and the second address line turns off the second transistor; and c. burning the first fuse by an appropriate voltage applied to the power source when the control circuit generates control signals commanding the second address to turn on the second transistor and the first address line to turn off the first transistor.
US Referenced Citations (7)
Number Name Date Kind
5363134 Barbehenn et al. Nov 1994 A
5504507 Watrobski et al. Apr 1996 A
5757394 Gibson et al. May 1998 A
5940095 Parish et al. Aug 1999 A
5966144 Edwards Oct 1999 A
6022094 Gibson et al. Feb 2000 A
6568783 Hu et al. May 2003 B2