Fig. 4. 6T SRAM cell
Stability Metrics
The objective pertaining to this paper implies to explore the
suitability of two methods, namely the SNM metric and N curve method,
for evaluating the reliability concerning an Static Random Access Memory
cell. Emphasis is placed on the N curve method due to the drawbacks
associated with using the SNM metric butterfly curves approach, a
restrictive factor constitutes incapability with the intention of
automatically measuring the SNM using inline testers, time-consuming
mathematical calculations, and imprecise results due to the need to fit
squares in each lobe to determine the SNM. Therefore, the N curve method
is considered more appropriate as it offers higher accuracy and does not
require complex mathematical calculations.
Results
Static Noise Margin
The primary determinant of an SRAM cell’s stability is its capacity to
withstand and maintain reliable operation when subjected to high levels
of DC noise voltage, which is commonly referred to as the SNM (Static
Noise Margin).