ECE Seminar: Power Supply Impedance Emulation for LSI Testing
Friday, February 3, 2017 - 12:00pm to 1:00pm
Naoki Terao, Department of Electrical Engineering and Information Systems, the University of Tokyo
In semiconductor test, mismatch of power supply integrity between an automatic test equipment (ATE) and a customer board can lead to test failures.This talk will discuss a technique to control the power supply impedance of an ATE by feedback control using compensation current injection so that it emulates the impedance of a customer board, so as not to produce test failures coming from the impedance difference between the two environment.Our technique adjusts the equivalent impedance by injecting compensation current by a current source attached in parallel with the power supply source. The compensation current is calculated and injected in realtime with a feedback manner based on the power supply voltage measurement with the impedance characteristics of ATE's original power delivery network (PDN) and the customer PDN. Experimental results of prototype circuits are demonstrated to show that the compensation current emulates the impedance, and the both power supply voltage fluctuation waveforms agree well.