Abstract: A semiconductor device under test (DUT) is checked, particularly for its wirebond integrity, by comparison with an identical reference device which is known good. Each of the DUT and reference device equally has pins. A current is selectively supplied to each pin of the reference device to provide a reference voltage drop at the reference device. Similarly, an identical current is selectively supplied to each pin of the DUT to measure a voltage drop at the DUT. The voltage drop at the DUT is compared with the reference voltage drop to provide a difference. Finally, determination is made as to whether the difference is within a tolerable range.