Test apparatus and test method

Abstract

A test apparatus for testing a device under test including a receiving circuit for receiving signals transmitted through a communication cable is provided. The test apparatus includes: an waveform generating section for outputting waveform data to define an waveform to be provided to an input terminal of a receiving circuit; a digital filter having the filter characteristic substantially reverse to the attenuation characteristic of the communication cable, for outputting amplified waveform data obtained by amplifying the waveform data; a DA converter for converting the amplified waveform data to an analog waveform; and a low-pass filer having the attenuation characteristic substantially the same as that of the communication cable, for attenuating the analog waveform and providing the same to the receiving circuit.

1 . A test apparatus for testing a device under test including a receiving circuit for receiving signals transmitted through a communication cable, comprising: 
 an waveform generator for outputting waveform data to define an waveform to be provided to an input terminal of the receiving circuit;    a digital filter having filter the characteristic substantially reverse to the attenuation characteristic of the communication cable, for outputting amplified waveform data obtained by amplifying the waveform data;    a DA converter for converting the amplified waveform data to an analog waveform; and    a low-pass filter having the attenuation characteristic substantially the same as that of the communication cable, for attenuating the analog waveform and providing the same to the receiving circuit.    
     
     
         2 . The test apparatus according to  claim 1 , wherein the minimum voltage step of converting by the DA converter is larger than the maximum voltage of the analog waveform provided from the low-pass filer to the receiving circuit.  
     
     
         3 . The test apparatus according to  claim 1 , wherein 
 the communication cable includes a plurality of transmitting paths;    the receiving circuit includes the plurality of input terminals for receiving the signal from each of the plurality of transmitting paths, respectively, and    the waveform generator outputs the plurality of waveform data which should be provided to the plurality of input terminals and which include the effect of interference generated in the plurality of transmitting paths.    
     
     
         4 . The test apparatus according to  claim 1  further comprising a simulation section for calculating by simulating a receiving waveform inputted to the input terminal of the receiving circuit after an output signal of a transmitting circuit for transmitting a signal to the receiving circuit through the communication cable is passed through the communication cable, wherein 
 the waveform generating section acquires digital data of the receiving waveform and outputs the same as the waveform data.    
     
     
         5 . A test method for testing a device under test including a receiving circuit for receiving signals transmitted through a communication cable, comprising: 
 outputting waveform data to define an waveform to be provided to an input terminal of the receiving circuit;    outputting amplified waveform data obtained by amplifying the waveform data with the filter characteristic substantially reverse to the attenuation characteristic of the communication cable;    converting the amplified waveform data to an analog waveform; and    attenuating the analog waveform and providing the same to the receiving circuit with the attenuation characteristic substantially the same as that of the communication cable.    
     
     
         6 . The test method according to  claim 5  further comprising calculating by simulating a receiving waveform inputted to the input terminal of the receiving circuit after an output signal of the transmitting circuit for transmitting a signal to the receiving circuit through the communication cable is passed through the communication cable, wherein 
 the waveform generating step acquires digital data of the receiving waveform and outputs the same as the waveform data.