STUDENT PAPER: Debugging Signal Corruption in Scan Chain using Phase Laser Voltage Imaging

Thursday, November 9, 2017: 2:45 PM
Ballroom A (Pasadena Convention Center)
Mr. Gopinath ranganathan , Advanced Micro Devices - Singapore Pte Ltd1, Singapore, Singapore
Mr. Venkat Ravikumar , SIngapore University of Technology and Design, Singapore, Singapore
SL Phoa , Advanced Micro Devices - Singapore Pte Ltd, Singapore, Singapore
Prof. KL pey , Singapore University of Technology and Design, Singapore, Singapore
Mr. Neel Leslie , FEI Company, Fremont, CA
Mr. Christopher Nemirow, Ph.D , FEI Company, Fremont, CA

Summary:

Laser Voltage imaging (LVI) is an established technique for isolating scan chain failures, especially those that are stuck-at a particular state. Enhancements such as second harmonic mapping have been beneficial in detecting a fault that is not stuck, but caused a shift in duty-cycle of the injected signal. Here, we describe Phase LVI constructed by integrating a lock-in amplifier as an enhancement to LVI for studying the relative phases between scan flops. Additionally we showcase a case study of successful fault isolation using phase LVI, where traditional LVI techniques weren’t successful