IMPLEMENTING ENHANCED PSEUDO RANDOM PATTERN GENERATORS WITH HIERARCHICAL LINEAR FEEDBACK SHIFT REGISTERS (LFSRs)

摘要

A method and circuit for implementing enhanced Logic Built In Self Test (LBIST) diagnostics, and a design structure on which the subject circuit resides are provided. A plurality of pseudo random pattern generators (PRPGs) is provided, each PRPG comprising one or more linear feedback shift registers (LFSRs). Each respective PRPG includes an XOR feedback input selectively receiving a feedback from another PRPG and predefined inputs of the respective PRPG. A respective XOR spreading function is coupled to a plurality of outputs of each PRPG with predefined XOR spreading functions applying test pseudo random pattern inputs to LBIST channels for LBIST diagnostics.