Bit line charge sharing for sram dynamic power savings
AssigneeQUALCOMM Incorporated
InventorsHochul LEE, Anil Chowdary KOTA, Chulmin JUNG
Life of this patent
Estimating the term…
Abstract
A bit line charge sharing precharge circuit is provided that precharges a bit line pair during a charge sharing period in which the bit line pair is isolated from a memory power supply voltage. Prior to the charge sharing period, one of the bit lines in the bit line pair was charged to the memory power supply voltage whereas a remaining one was either fully or partially discharged. Charge thus flows from the charged bit line to the discharge bit line during the charge sharing period to precharge the bit lines for a current read or write operation.
Claims20
A bit line charge sharing precharge circuit, comprising:
- a bit line;
- a complement bit line
- a first switch coupled between the bit line and complement bit line;
- a power supply node for a memory power supply voltage;
- a precharge node;
- a second switch coupled between the precharge node and the power supply node;
- and
- a third switch coupled between the precharge node and the complement bit line.
A method of precharging a pair of bit lines, comprising:
- coupling a precharge node to a node for a memory power supply voltage during a first precharge period to precharge the precharge node;
- isolating the precharge node from the node for the memory power supply voltage after a completion of the first precharge period;
- coupling a bit line to a complement bit line during a charge sharing period following the completion of the first precharge period;
- and
- coupling the precharge node to the bit line and to the complement bit line during the charge sharing period.
A memory, comprising:
- a bit line;
- a complement bit line;
- precharge means for precharging a precharge node during a precharge period;
- and
- means for coupling the bit line to the complement bit line and to the precharge node during a charge sharing period following the precharge period.
Dependencies are inferred from the claim text.