Convolution/deconvolution SRAM analyses for complex gamma mixtures RTN distributions

摘要

This paper discusses, for the first time, how the statistical SRAM design analyses should be changed when: (1) the time-dependent (TD) voltage margin variations (MV) after the screening test will dominate the overall behavior of the MV variations and (2) the shapes of the MV distribution will change from the Gaussian to the complex mixtures of Gamma distributions. We discuss on the SRAM TD-MV analyses with not only the forward problem but also the inverse problem, i.e., deconvolution analyses. The proposed algorithm for the deconvolution to circumvent the issues caused by a high-pass filtering behavior is discussed. The results given by the proposed convolution /deconvolution design analyses have shown that the followings have been enabled: (1) to figure out the unknown truncating point (TP) based on the overall final MV distributions as a reverse-engineering, (2) to decide the aimed TP/RDF/RTN required to achieve a target specs, and (3) to work out the required MV-shift-amount by the assisted circuit schemes to avoid any out of specs in the market during the life-time.