Method for selectively conditioning integrated circuit outputs for

Abstract

A method for automatically generating an in-circuit board test for a circuit board, comprising a plurality of Interconnected digital devices, selectively provides conditioning only to devices which need conditioning. Devices which need conditioning include outputs which should be conditioned prior to being back-driven and problem devices (such as oscillators) which interfere with the testing of other devices. The device outputs which require conditioning are flagged in a device models library which contains predetermined generic test models for the devices on the board. The method for conditioning back-driven devices comprises selecting a device under test (DUT), receiving electrical interconnect data for the devices on the circuit board, determining from the electrical interconnect data which device outputs are driving the inputs of the DUT, determining from the device models library which back-driven outputs should be conditioned, and conditioning any back-driven outputs which are flagged CONDITION in the device models library. The method for conditioning problem devices includes flagging the problem devices in the device models library, determining whether any problem devices exist on the board, determining from the electrical interconnect data which devices are affected by a problem device, and indicating for each affected devcice which of said problem device outputs are to be conditioned prior to testing said affected device. If the DUT is an affected device, then any problem device outputs which affect it will be conditioned prior to testing the DUT. Generation of the in-circuit test is completed by retrieving from the device models library conditioning methods for each device to be conditioned, combining the conditioning methods together to form a test statement, retrieving a test method for testing the DUT from the device models library, and then merging the test statement for conditioning with the test method for testing the DUT.