Boosting a digit line voltage for a write operation
View Patent ↗Methods, systems, and devices for operating a ferroelectric memory cell or cells are described. The magnitude of a voltage applied across a ferroelectric capacitor may be dynamically increased during a write operation. For example, a memory cell may be selected for a write operation, and a voltage may be applied to a digit line corresponding to the memory cell during the write operation. An additional charge may be transferred to the digit line—e.g., from an energy storage component, such as a capacitor, that is in electronic communication with the digit line. In turn, the voltage across the ferroelectric capacitor of the memory cell may be increased.
1. A method of operating a memory cell, comprising:
selecting the memory cell for a write operation, the memory cell comprising a ferroelectric capacitor that is in electronic communication with a digit line;
applying a first voltage to the digit line during the write operation; and
applying a second voltage to an additional capacitor that is in electronic communication with the digit line during the write operation.
2. The method of claim 1 , further comprising:
activating a switching component that is in electronic communication with the additional capacitor and the digit line during the write operation.
3. The method of claim 2 , further comprising:
determining that a voltage of the digit line has reached a threshold associated with applying the first voltage; and
activating the switching component based at least in part on the determination that the voltage of the digit line has reached the threshold.
4. The method of claim 2 , wherein the second voltage is applied to a first plate of the additional capacitor after the switching component is activated.
5. The method of claim 4 , further comprising:
virtually grounding the digit line before selecting the memory cell for the write operation.
6. The method of claim 5 , wherein a second plate of the additional capacitor is in electronic communication with the digit line via the switching component, and wherein the method further comprises:
virtually grounding the first plate of the additional capacitor after selecting the memory cell for the write operation.
7. The method of claim 6 , further comprising:
deactivating the switching component after virtually grounding the first plate of the additional capacitor.
8. The method of claim 2 , further comprising:
isolating the digit line after activating the switching component and prior to applying the second voltage.
9. The method of claim 1 , wherein a constant voltage is applied at a plate line that is in electronic communication with the memory cell, and wherein the method further comprising:
applying a third voltage to the digit line after the write operation, wherein a magnitude of the third voltage is equal to the constant voltage.
10. The method of claim 9 , further comprising:
virtually grounding the digit line for a read operation after applying the third voltage.
11. The method of claim 1 , wherein applying the first voltage comprises:
triggering a sense component that is in electronic communication with the digit line to apply the first voltage to the digit line.
12. The method of claim 1 , wherein the additional capacitor is a ferroelectric capacitor of a second memory cell that is in electronic communication with the digit line.
13. A method of operating a memory cell, comprising:
selecting the memory cell for a write operation, the memory cell comprising a ferroelectric capacitor that is in electronic communication with a digit line;
applying a first voltage associated with a voltage supply to the digit line during the write operation; and
transferring charge onto the digit line from an energy storage component after applying the first voltage.
14. The method of claim 13 , wherein the energy storage component is in electronic communication with the digit line via a switching component, and wherein the method further comprises:
activating the switching component.
15. The method of claim 14 , further comprising:
charging the energy storage component during the write operation, wherein transferring the charge onto the digit line comprises:
discharging the energy storage component onto the digit line.
16. The method of claim 13 , wherein applying the first voltage comprises triggering a sensing component that is in electronic communication with the digit line and the voltage supply.
17. The method of claim 13 , wherein the memory cell is in electronic communication with a plate line, and wherein a constant voltage is applied to the plate line.
18. An electronic memory apparatus, comprising:
a memory cell comprising a ferroelectric capacitor that is in electronic communication with a digit line;
an additional capacitor in electronic communication with the digit line; and
a controller in electronic communication with the memory cell, and the additional capacitor, wherein the controller is operable to:
select the memory cell for a write operation;
apply a first voltage to the digit line during the write operation; and
apply a second voltage to the additional capacitor during the write operation.
19. The electronic memory apparatus of claim 18 , further comprising a switching component that is in electronic communication with the additional capacitor, and wherein the controller is operable to:
determine that a voltage of the digit line has reached a threshold associated with applying the first voltage; and
activate the switching component based at least in part on the determination that the voltage of the digit line has reached the threshold.
20. The electronic memory apparatus of claim 19 , wherein the controller is operable to:
apply the second voltage to a first plate of the additional capacitor after activating the switching component.
21. The electronic memory apparatus of claim 20 , wherein the controller is operable to:
virtually ground the digit line before selecting the memory cell.
22. The electronic memory apparatus of claim 21 , wherein a second plate of the additional capacitor is in electronic communication with the digit line via the switching component, and wherein the controller is operable to:
virtually ground the first plate of the additional capacitor after selecting the memory cell.
23. The electronic memory apparatus of claim 22 , wherein the controller is operable to:
deactivate the switching component after virtually grounding the first plate of the additional capacitor.
24. The electronic memory apparatus of claim 19 , further comprising a plate line in electronic communication with the memory cell, and wherein the controller is operable to:
apply a constant voltage to the plate line; and
apply a third voltage to the digit line after the write operation, wherein a magnitude of the third voltage is equal to a magnitude of the constant voltage.
25. The electronic memory apparatus of claim 24 , further comprising a sense component that is in electronic communication with the digit line, and wherein the controller is operable to:
isolate the digit line from the sense component after activating the switching component and before applying the second voltage.