1. US20070024311 - Semiconductor test apparatus

Good device PASS/FAIL determination is realized by measuring timings of a cross point of differential clock signals CLK and a data signal DATA output from a DUT, and obtaining a relative phase difference between both signals. A semiconductor test apparatus comprises differential signal timing measurement means for outputting cross point information Tcross obtained by a timing of a cross point of one of differential signals, non-differential signal timing measurement means for outputting data change point information Tdata obtained by a timing of transition of a logic of the other non-differential signal output, phase difference calculation means for outputting a phase difference ΔT between the cross point information Tcross and the data change point information Tdata, and PASS/FAIL determination means for determining PASS/FAIL of a relative positional relationship of the DUT based on a predetermined threshold value.