公开(公告)号：US20200065456A1

公开(公告)日：2020-02-27

申请号：US16535795

申请日：2019-08-08

Applicant: UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC.

Inventor： Mark M. Tehranipoor ,  Domenic J. Forte ,  Farimah Farahmandi ,  Adib Nahiyan ,  Fahim Rahman ,  Mohammad Sazadur Rahman

IPC: G06F21/14 ,  H03K19/177 ,  G06F21/72 ,  G06F12/14

Abstract: A dynamically obfuscated scan chain (DOSC) includes a control module designed to control memory loading, a linear feedback shift register (LFSR), a dynamic Obfuscation Key generator configured to use LFSR to generate a φ-bit protected Obfuscation Key, in order to confuse and change the test data into an output scan vectors when the Obfuscation Key update is triggered. The DOSC also includes a shadow chain, configured to input the φ-bit protected Obfuscation Key generated by the LFSR, and output k └φ×α┘-bit protected Obfuscation Keys, and obfuscated scan chains. The DOSC operating method includes: loading control vectors to LFSR from control module during initialization; generating the Obfuscation Key at an output of the LFSR; generating the Obfuscation Key bit by bit based at least in part on the shadow chain and the Obfuscation Key during a first scan clock after reset in order to confuse test patterns.