Power application test apparatus and method of mixing logic circuit of conventional and boundary-scan

摘要

PURPOSE: To provide a method for testing a circuit board having both of a boundary scanning(BS) element and a non-boundary scanning(NBS) element. ;CONSTITUTION: BS nodes 31A-31D are distinguished from NBS nodes 32A-32C, a large number of pairs of NBS nodes which are within a prescribed distance R from element pins to be joined with BS nodes are determined by utilizing a Cartesian coordinates (X, Y) of all pins of all elements on a circuit board. The number of the NBS node are divided into independent groups to be tested in parallel. Drivers 37 for the BS elements are forced to be in a first logical state and respective NBS nodes are formed in logical state for respective short periods and NBS node tests are carried out independently in parallel, so that the testing cycle is carried out. Receivers 38 on the BS elements capture response vector within a short period and the results are scanned and sent out of the circuit board for evaluation.;COPYRIGHT: (C)1995,JPO