Abstract: An IC testing apparatus in which an accident occurring when a measurement part mounted on a test head is changed can be avoided. A type signal generating device 301 is provided on each of measurement parts so that a type signal TYPE can be sent from the type signal generating device 301 when a measurement part 300 is mounted on a test head 200. The type signal is read by a type signal reading device 102 provided in an IC tester 100. The type signal is transmitted to a handler 400 together with the number of simultaneous tests SUM extracted from a test program loaded in a main controller 101 of the IC tester. In the handler, a decision device 402 determines, based on the transmitted number of simultaneous tests and the type signal, whether or not the test program is proper and whether or not the arrangement of IC sockets set in the handler coincides with the arrangement of IC sockets of the measurement part.

Abstract: An instantaneous differential non-linearity DNL can be determined with a high accuracy with a reduced volume of computation and independently from a testing frequency while allowing an evaluation of factors in a compounded fault. A sine signal is applied to an AD converter 14 under test, a conversion output of which is divided into a sine component and a cosine component, with local maxima or minima aligned with each other. A square sum of the individual samples is formed, and a square root of the square sum is formed to determine an instantaneous amplitude (21). The amplitude of the sine wave signal is interleaved into a series of instantaneous amplitudes (20), and a first stage of the wavelet transform (46) is applied to the interleaved series of instantaneous amplitudes, with its output being oversampled to perform a second stage of wavelet transform (46′). A maximum amplitude of the transform output is detected by peak detector 23′. A detected value is used to estimate the DNL.