A memory stores manufacturing information including at least the number of refills, an electronic signature of the manufacturing information, and a first error-detecting code of the manufacturing information. The number of refills is the number of times that, after consumption of a liquid contained in the cartridge, the cartridge is refilled with the liquid.

A liquid cartridge includes a case, a liquid supply portion, a circuit board, a residual-amount detecting portion, a base surface, and a plate member. The residual-amount detecting portion includes an optical access portion accessible by light traveling in a left-right direction. The optical access portion has a portion positioned above and away from electrodes of the circuit board by a first distance in an attached posture. The plate member extends frontward from the base surface, and provides a light-shielding region and a light-transmissive region. The light-shielding region is positioned rearward of the electrodes and frontward of the residual-amount detecting portion. The light-transmissive region is positioned rearward of the light-shielding region and frontward of the residual-amount detecting portion. Each of the light-transmissive region and the light-transmissive region has a portion positioned above and away from the electrodes by the first distance in the attached posture.

A liquid cartridge includes: a cartridge case defining a liquid storage chamber; a liquid supply portion provided at the cartridge case; a residual-amount detecting portion configured to change a state of incident light according to an amount of liquid stored in the liquid storage chamber; and a plate member. The residual-amount detecting portion includes an optical access portion accessible by light traveling in a left-right direction in an attached posture of the liquid cartridge. The plate member is positioned above the liquid storage chamber and frontward of the optical access portion in the attached posture. The plate member is pivotable between a first position and a second position about an axis extending in an up-down direction. In the attached posture of the liquid cartridge, the plate member extends in a front-rear direction at the first position, and extends in a direction crossing the front-rear direction at the second position.

A liquid cartridge includes a case, a liquid supplying portion, a circuit board, a plate member, and a residual-amount detecting portion. The plate member is positioned rearward and above electrodes of the circuit board in an attached posture. The residual-amount detecting portion includes an optical access portion configured to receive light traveling in a left-right direction. The plate member is movable between a first position and a second position. At the first position, a portion of the plate member is positioned frontward of the optical access portion and upward of the electrode group. At the second position, a front end of the plate member is positioned closer to the residual-amount detecting portion than at the first position. The plate member at the first position and the residual-amount detecting portion define therebetween in the front-rear direction a light transmissive region whose light transmittance is higher than the plate member.

A liquid cartridge includes: a cartridge case defining therein a liquid storage chamber; a liquid supply portion; a circuit board; a plate member; and a residual-amount detecting portion. The residual-amount detecting portion is configured to change a state of incident light according to an amount of the liquid stored in the liquid storage chamber, and includes an optical access portion on which light traveling in a left-right direction is incident. The plate member is pivotally movable between: a first posture where a portion of the plate member is positioned upward relative to the optical access portion; and a second posture where the plate member is positioned downward relative to the optical access portion. The plate member in the first posture and the residual-amount detecting portion define a light transmissive region therebetween in the front-rear direction. The light transmissive region has a light transmittance greater than that of the plate member.

In one embodiment a print liquid supply apparatus is provided to supply liquid to a liquid needle of a receiving station comprising a liquid container including an at least partially collapsible liquid reservoir an interface structure at a side of the container, including a liquid channel that includes a reservoir connecting portion that fluidically connects to the reservoir and a needle receiving portion to allow the liquid to flow from the reservoir to the needle; a liquid interface of the liquid channel adjacent the needle receiving portion and at a distance from the reservoir connecting portion, a front wall and/or edge adjacent the liquid interface including a push area which is disposed between the liquid interface and the container; and at least one key pen base and key pen protruding from the base in a direction parallel and opposite to the needle insertion direction; and a contact pad array next to the needle receiving liquid channel portion. In another example a sub-assembly of such apparatus is provided.

A memory cell includes an input coupled to a read line, an output coupled to a circuit ground, a bi-polar memristor, and at least one address switch coupled to an address line to select the memory cell. A memory includes the bi-polar memristor and a one-way current conducting device, wherein the one-way current conducting device is positioned between the memristor cell output and the circuit ground, or between the read line and the memristor cell input.

A liquid cartridge configured to be inserted into a cartridge attachment section includes: a cartridge body having a liquid storage chamber, and a liquid supply portion configured to supply the liquid stored in the liquid storage chamber to an outside. The liquid supply portion includes: a front end face facing frontward, an outer peripheral surface extending rearward from the front end face, and at least one guide provided at the outer peripheral surface. Each of the at least one guide is guided by corresponding at least one projection of the cartridge attachment section during attachment of a liquid supply tube of the cartridge attachment section to the liquid supply portion at a time of attachment of the liquid cartridge to the cartridge attachment section. Each of the at least one guide includes: a first guide portion, and a second guide portion.

Examples of conductive connections are described herein. Some examples of a fluid ejection device may include an electrically conductive non-metal structure in contact with fluid in a fluid reservoir. Some examples of the fluid ejection device may include conductive adhesive forming a conductive connection between the electrically conductive non-metal structure and circuitry.

A liquid cartridge includes: a housing including first and second protrusions; and a circuit board including an electrode. The first protrusion is positioned rearward but the second protrusion is positioned forward relative to the circuit board. When viewed in a width direction crossing a gravitational direction, an outline of the liquid cartridge between a first point and a second point is lower than an imaginary line. The imaginary line passes through the first point on the first protrusion and the second point on the second protrusion. A distance between a front edge of the electrode and the first point is smaller than a distance between the front edge and the second point. A dimension between a front end and a rear end of the second protrusion is greater than a distance between a frontmost end of the housing and the front end of the second protrusion.