High-resolution readout of analog memory cells

摘要

A method includes storing data in an analog memory cell by writing an analog value into the memory cell. After storing the data, the data stored in the memory cell is read by discharging electrical current to flow through the memory cell, during a predefined time interval, while applying a variable voltage to a gate of the memory cell. A fraction of the predefined time interval, during which the variable voltage allows the electrical current to flow through the memory cell, is estimated. The stored data is estimated based on the estimated fraction.

主权项

1. A method, comprising:
storing data in an analog memory cell by writing an analog value into the memory cell; and after storing the data, reading the data stored in the memory cell by:
during a predefined time interval, discharging electrical current to flow through the memory cell while applying a variable voltage to a gate of the memory cell, wherein discharging the electrical current comprises charging a capacitance that is connected in series with the memory cell;estimating a fraction of the predefined time interval during which the variable voltage allows the electrical current to flow through the memory cell, wherein estimating the fraction comprises measuring an integral of the electrical current flowing through the memory cell over the predefined time interval, and wherein measuring the integral of the electrical current comprises measuring an electrical charge level of the capacitance following the predefined time interval; andestimating the stored data based on the estimated fraction.