Characterization of Random Access Memories: Strategies, Test Patterns and Parameters Involved in the Characterization of RAM Memories and an Evaluation of 16 K RAM's of Eight Manufactures

摘要

Techniques for the testing and characterization of dynamic random access memories (RAM's) are described. The general background of RAM operations and related failure modes are discussed. This includes descriptions of typical RAM sensitivities due to supply voltage variations, supply voltage interactions, extreme temperatures, test patterns, operational modes, and timing conditions. An operating region can be defined for each device under test. In addition it is shown how the characterization will result in worst case test conditions for use in production testing. A characterization of eight manufactures of industry standard 16 k x 1 bit dynamic RAMS's is carried out and the sensitivities revealed are described and commented on.