| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor test apparatus to cope with a speed-up of tested devices. SOLUTION: The apparatus is equipped with a reference signal generating circuit, and phase adjusting circuits provided to coping respectively with output pins of a tested device. Each phase adjusting circuit comprises: a comparative signal generating circuit to generate a comparative signal, based on a reference signal; a strobe signal generating circuit to generate a strobe signal, based on the reference signal; a first delay circuit to delay the comparative signal; a second delay circuit to delay the strobe signal; a phase comparing circuit to output a phase difference signal indicating a phase difference between a device output signal and the comparative signal; a latch circuit to latch the device output signal by synchronizing with the strobe signal; and an arithmetic circuit to compute a delay control amount, based on the phase difference signal so that the phase difference is constant between the device output signal and the comparative signal and, to output a delay control signal indicating the delay control amount to the first delay circuit and the second delay circuit. COPYRIGHT: (C)2009,JPO&INPIT
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