Patent Number: 6,401,225

Title: Comparator circuit for semiconductor test system

Abstract: A comparator circuit includes a window high impedance detector which detects any glitches or fails in the high impedance state of the device under test (DUT) within a specified time range. The comparator circuit includes a first analog comparator for receiving an output signal of the DUT and comparing the output signal with a high threshold voltage, a second analog comparator for receiving the output signal of the DUT and comparing the output signal with a low threshold voltage, and a window high impedance detector for detecting a deviation from a high impedance state of the DUT throughout a specified time range and for producing a fail signal when the deviation is detected.

Inventors: Miura; Takeo (Tatebayashi, JP)

Assignee: Advantest Corp.

International Classification: G01R 19/165 (20060101); G01R 31/3193 (20060101); G01R 31/317 (20060101); G01R 31/28 (20060101); G01R 031/28 ()

Expiration Date: 06/04/2019