Sense amplifier incorporating a symmetric midpoint reference
US6621729B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2002 |
| Grant date | Sep 16, 2003 |
| Priority date | — |
| Expiry date | Jun 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2207/063
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A sense amplifier (10) develops internally a midpoint reference current from two reference bits. The midpoint reference current is used to sense the state of a memory bit having at least two distinct resistance states (H and L) by determining whether the sense memory bit develops a larger or smaller current. The midpoint reference current is developed within a single sense amplifier. Predetermined bias voltages are developed from each of a data bit cell, a reference cell programmed to a high state and a reference cell programmed to a low state. Currents are developed from the bias voltages and summed to create the midpoint reference current. A current differential amplifier senses whether the bit input has a high or low resistive state and outputs a voltage indicative of the sensed memory state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.