Patents Examined by Mathew C. Dooley
  • Method and apparatus for testing semiconductor devices
    Patent number: 6789224
    Abstract: Data output from a semiconductor device under test and a reference clock output therefrom in synchronization with the data are sampled by slightly phased-apart multiphase strobe pulses. The phases of points of change of the output data and the reference clock are obtained from the sampled outputs, then the phase difference between them is measured, and a check is made to determine if the phase difference falls within a predetermined range, thereby evaluating the semiconductor device under test on a pass/fail basis.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: September 7, 2004
    Assignee: Advantest Corporation
    Inventor: Takeo Miura