Storage apparatus, liquid discharge head, and liquid discharge apparatus
A storage apparatus, comprising a memory unit including an anti-fuse element and a resistance element connected in parallel to the anti-fuse element, and an information writer that writes information into the anti-fuse element by cyclically applying a signal to the memory unit, wherein the information writer changes a cycle of a signal to be applied to the memory unit on a basis of a current value supplied to the memory unit.
1 . A storage apparatus comprising:
a memory unit including an anti-fuse element, a resistance element connected in parallel to the anti-fuse element, and a switch element connected in series with the anti-fuse element, wherein if the switch element is in a conductive state a current is supplied to the anti-fuse element and if the switch element is in a non-conductive state the current is not supplied to the anti-fuse element;
a current detection unit for detecting a current value supplied to the memory unit; and
an information writer that writes information into the anti-fuse element by applying a cyclical signal to the switch element to change the state of the switch element between the conductive state and the non-conductive state,
wherein the anti-fuse element comprises a metal oxide semiconductor (MOS) structure,
wherein the current value detected by the current detection unit indicates a dielectric breakdown state of the MOS structure of the anti-fuse element,
wherein the information writer applies a first signal of having a first cycle to the switch element before a current value supplied to the memory unit reaches a first reference value, and applies a second signal having a second cycle larger than the first cycle to the switch element after the current value supplied to the memory unit reaches the first reference value, and
wherein the first reference value corresponds to a change in the MOS structure from a state before dielectric breakdown to a soft dielectric breakdown state.
2 . The storage apparatus according to claim 1 further comprising a protection element connected in parallel to the memory unit.
3 . The storage apparatus according to claim 2 , wherein with the resistance element as a first resistance element, the storage apparatus further includes a second resistance element disposed between a power source line for supplying a power source voltage to the memory unit and the memory unit.
4 . The storage apparatus according to claim 3 , wherein the information writer changes a cycle of a signal to be applied to the anti-fuse element on a basis of a current value supplied to the anti-fuse element specified by comparison between a voltage generated in the second resistance element and a reference voltage.
5 . A liquid discharge head comprising:
the storage apparatus according to claim 1 ; and
a liquid discharge element for discharging liquid.
6 . A liquid discharge apparatus comprising:
the liquid discharge head according to claim 5 ; and
a head controller for performing drive control of the liquid discharge head.
7 . The liquid discharge apparatus according to claim 6 ,
wherein the current detection unit is installed in the liquid discharge head.
8 . The liquid discharge apparatus according to claim 6 ,
wherein the current detection unit is installed in the head controller.
9 . The liquid discharge apparatus according to claim 6 further comprising:
a carriage configured to move the liquid discharge head on a basis of a control signal from the head controller,
wherein the current detection unit is installed in the carriage.