Printhead cartridge interface having power regulation

1 . A system for interconnecting a printhead cartridge and a cradle unit for supporting the printhead cartridge, the system comprising:

an interface at which the printhead cartridge is removably engageable with the cradle unit, the interface comprising connections for connecting the printhead cartridge with a power supply of the cradle unit; and

a power regulation circuit incorporated in the interface for regulating supply of power from the power supply to the printhead cartridge.

2 . A system according to claim 1 , wherein the power regulation circuit is configured to regulate the supply of power from the power supply so that ink ejection nozzles of a printhead incorporated in the printhead cartridge receive substantially constant power.

3 . A system according to claim 1 , wherein the interface incorporates a printed circuit board, the connections and power regulation circuit being arranged on the printed circuit board.

4 . A system according to claim 3 , wherein the connections of the interface are arranged to connect the printhead cartridge with print control circuitry of the cradle unit.

5 . A system according to claim 4 , wherein the print control circuitry is incorporated on a second printed circuit board, the first and second printed circuit boards having complementary connectors which cooperate to provide the connection of the printhead cartridge and print control circuitry.

6 . A system according to claim 5 , wherein the first printed circuit board is arranged so as to substantially orthogonally project from the second printed circuit through the cooperation of the complementary connectors.

7 . A system according to claim 6 , wherein the complementary connectors are arranged so that the first printed circuit board is able to pivot with respect to the second printed circuit board.

8 . A system according to claim 1 , wherein the power regulation circuit is configured to output a regulated voltage up to 5.5 Volts from a supply of 12 Volts from the power supply.

9 . A system according to claim 8 , wherein the power regulation circuit is configured to output a regulated current of 3.5 Amps from a supply of 2 Amps from the power supply.

10 . A system according to claim 8 , wherein the power regulation circuit is configured to output the regulated voltage with a maximum variation of 100 milliVolts.

11 . A system according to claim 1 , wherein the power regulation circuit incorporates a power storage circuit for storing at least some of the power being supplied to the printhead cartridge from the power supply.

12 . A system according to claim 11 , wherein the power storage circuit includes a plurality of capacitors for storing said power.

13 . A system according to claim 12 , wherein the capacitors include electrolytic and ceramic capacitors.

14 . A system according to claim 13 , wherein the electrolytic capacitors are 100 microFarad capacitors.

15 . A system according to claim 13 , wherein the electrolytic capacitors are tantalum capacitors.

16 . A system according to claim 13 , wherein eight of the electrolytic capacitors are arranged in parallel to store about 12 millijoules of energy.

17 . A system according to claim 13 , wherein the ceramic capacitors are 10 microFarad capacitors.

18 . A system according to claim 13 , wherein six of the ceramic capacitors are arranged in parallel to store about 900 microJoules of energy.

19 . A system according to claim 12 , wherein the power storage circuit further includes an inductor for storing some of said power.

20 . A system according to claim 19 , wherein the inductor is a 10 microHenry inductor.