Low impedance column multiplexer circuit and method
US7821866B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2007 |
| Grant date | Oct 26, 2010 |
| Priority date | — |
| Expiry date | Feb 2, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2207/002
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The invention has a bootstrapped high voltage pass gate transistor that couples the low voltage sense amplifier to the bitlines. Since the pass gate transistor is bootstrapped its gate floats to the high voltage of the power supply (VCC) plus a delta voltage. This overdrives the pass gate transistor and allows it to pass signals between the sense amplifier and the bitlines with low impedance. This results in good sense differential margins and fast read speeds. The circuit has a pass gate control circuit that places a negative high voltage signal on the gate of the pass gate during non-volatile write operations. This causes the pass gate to isolate the low voltage circuit from the high voltage circuits during this operation. Finally, the circuit is smaller than earlier column multiplexer circuits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.