Techniques for reducing rock bottom leakage in memory

1. A memory system comprising:

a word line (WL) driver circuit comprising a transistor coupled between a WL of a memory and a reference potential node; and

a clamping circuit comprising:

logic configured to generate a control signal to drive a gate of the transistor; and

a first head switch coupled between a voltage rail and a supply input of the logic, wherein the logic is configured to generate the control signal to drive the gate of the transistor such that the control signal is floating when the first head switch is open.

2. The memory system of claim 1 , wherein the first head switch is configured to be open during a sleep non-retention mode of operation of the memory system.

3. The memory system of claim 1 , wherein the logic comprises an inverter.

4. The memory system of claim 1 , wherein the control signal is configured to be logic high during a sleep retention mode of the memory system.

5. The memory system of claim 1 , wherein the WL driver circuit further comprises an inverter having an output coupled to a drain of the transistor.

6. The memory system of claim 1 , further comprising:

a second head switch coupled between a voltage rail and a supply input of a peripheral circuit; and

a third head switch coupled between the second head switch and a supply input of the WL driver circuit.

7. The memory system of claim 6 , wherein the second head switch is configured to be open during a sleep mode of operation of the memory system.

8. The memory system of claim 6 , wherein the logic is further configured to generate the control signal to drive the third head switch.

9. The memory system of claim 6 , wherein the peripheral circuit comprises logic configured to control the WL driver circuit.

10. The memory system of claim 1 , wherein the transistor comprises an n-type metal-oxide-semiconductor (NMOS) transistor.

11. A method for memory control, comprising:

generating, via logic of a clamping circuit, a control signal to drive a gate of a transistor of a word line (WL) driver circuit;

selectively coupling, via the transistor, a WL of a memory to a reference potential node based on the control signal; and

selectively coupling, via a first head switch of the clamping circuit, a voltage rail to a supply input of the logic such that the control signal is floating when the first head switch is open.

12. The method of claim 11 , wherein the selectively coupling the voltage rail to the supply input comprises opening the first head switch during a sleep non-retention mode of operation.

13. The method of claim 11 , wherein the logic comprises an inverter.

14. The method of claim 11 , wherein generating the control signal comprises setting the control signal to logic high during a sleep retention mode.

15. The method of claim 11 , wherein the WL driver circuit further comprises an inverter having an output coupled to a drain of the transistor.

16. The method of claim 11 , further comprising:

selectively coupling, via a second head switch, the voltage rail to a supply input of a peripheral circuit; and

selectively coupling, via a third head switch, the second head switch to a supply input of the WL driver circuit.

17. The method of claim 16 , wherein selectively coupling the voltage rail to the supply input of the peripheral circuit comprises opening the second head switch during a sleep mode of operation.

18. The method of claim 16 , wherein the control signal is further generated to drive the third head switch.

19. The method of claim 16 , further comprising controlling, via logic of the peripheral circuit, the WL driver circuit.

20. The method of claim 11 , wherein the transistor comprises an n-type metal-oxide semiconductor (NMOS) transistor.