Patent ID: 8278961
Filing Date: 2012-10-02
Classification: G01R

Abstract:
1. A test apparatus for performing, on a device under test, both i) an eye mask test for determining whether an eye opening of a signal under test is larger than a predefined eye mask and ii) a functional test different from the eye mask test, the apparatus comprising: a level comparing section that, during both the eye mask test and the functional test, receives a signal under test output from the device under test and outputs a logical value, the logical value indicating a comparison result obtained by comparing a signal level of the signal under test with preset first threshold and second threshold; an acquiring section that, during both the eye mask test and the functional test, acquires the logical value output from the level comparing section, according to a strobe signal supplied thereto; an expected value comparing circuit that, during both the eye mask test and the functional test, determines whether the logical value acquired by the acquiring section corresponds to a preset expected value; and a threshold control section that, i) during the eye mask test, sets an upper limit and a lower limit of a voltage of a predefined eye mask in the level comparing section as the first threshold and the second threshold, and, ii) during the functional test, prestores voltage levels defining high and low logic levels of the signal under test, as the first threshold and the second threshold, to be set in the level comparing section.