Furthermore, current programming methods must take into account device variations due to imperfections in the fabrication process, and how to control uniform level distribution in order to increase noise margin and process variation tolerance. Nevertheless, the programming operations lead to high programming latency and energy in some cases, and increase complexity due to the higher number of voltage regulators needed to supply different voltage levels. The main limitation of the existing programming solutions is that the controller should know the desired value for programming in order to apply the appropriate pulses.
In order to deal with such a problem, programming methods purpose to apply pre-known programming pulses according to the desired state or perform an iterative program and verify operations which increase energy and programming latency. Using fixed programming pulses leads to a non-uniform level distribution and state-dependent programming which burdens the controller and demands a modified programming techniques. Some Multi-Level-Cell memories suffer from nonlinearity in their switching mechanism (e.g., ReRAM).
0 kommentar(er)
