Device for reading analog nonvolatile memory cells, in particular flash cells
US6195289A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Oct 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C27/02
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A read device comprises a sense amplifier having an input connected to a data memory cell to be read and an output issuing a signal correlated to the threshold voltage of the data memory cell. A first and second voltage sources circuit have respect first and second outputs that supply respective first and a second input reference voltage. A resistive divider connected between the first and the second outputs of the voltage source circuits has a plurality of outputs supplying respective intermediate reference voltages having values between the first and the second input reference voltages. A plurality of comparator circuits have a first input connected to the output of the sense amplifier, a second input connected to a respective output of the resistive divider, and an output supplying a digital signal indicative of the outcome of a respective comparison. Each voltage source circuit comprises a nonvolatile reference memory cell of the same type as the data memory cell and having an own threshold voltage correlated to the input reference voltage, supplied by the voltage source circuit. Thereby, the input reference voltages, and thus the intermediate reference voltages supplied to the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.