Abstract: An antibody-drug conjugate represented by formula (I): (where Ab is an antibody, X is a group represented by formula (X-1), formula (X-2) or formula (X-3): (where at the left represents the binding site with NH and at the right represents the binding side with D), D is a group represented by formula (D-1) or formula (D-2): (where represents the binding site with X), and n is in the range of about 1 to about 8).

Abstract: A memory tester including an algorithmic pattern generator (ALPG) for generating a test pattern as a digital signal based on vector data is provided with a digital-to-analog converter built in the memory tester or provided outside the memory tester. Thus, the function of a device under test (DUT) having the analog-to-digital converting function can be verified. In other words, an address signal included in the test pattern generated in the ALPG is used for generating an analog signal to be input to the DUT having the analog-to-digital converting function, not for address designation. A control unit compares an output digital signal generated in the DUT with the address signal generated in the ALPG as a test digital signal to detect the degree of agreement between these signals, thereby verifying the analog-to-digital converting function of the DUT.