Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: A method for evaluating and correcting a model of an electronic circuit. A list is created which comprises the minimum number of components that must be specified by the operator in order to be able to compute values for the remaining circuit components. Correction of circuit models can be performed even in cases of limited accessibility to the circuit's nodes.

Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: A system that can test individual components having tolerances on a circuit board without complete access to every node on the board is disclosed. The system uses a method that develops test limits from a model of the board, component tolerances, and a list of accessible nodes. A method of reducing the complexity of the test problem by limiting the number of components under consideration is also disclosed. A method of reducing the complexity of the test problem by limiting the number of nodes under consideration is also disclosed. A method of picking nodes to apply stimulus to a board is also disclosed. Finally, a method of correcting for certain parasitics associated with tester hardware is disclosed.

Abstract: An electromagnetic probe is integrated within an integrated circuit or mounted within an IC package to provide a capability for testing continuity between the integrated circuit and a substrate to which the integrated circuit is mounted. In a first embodiment, capacitive test probes are integrated within the integrated circuit, underneath bonding pads. In a second embodiment, Hall-effect devices are integrated within the integrated circuit underneath bonding pads. In a third embodiment, an inductive loop is integrated within the integrated circuit underneath bonding pads. In a fourth embodiment, an IC package assembly includes an internal capacitive test probe for electrical continuity testing. An internal shield may also be used as a capacitive test probe. In a fifth embodiment, an IC package assembly includes an inductive loop within the package for electrical continuity testing.

Abstract: An electromagnetic probe is integrated within an integrated circuit or mounted within an IC package to provide a capability for testing continuity between the integrated circuit and a substrate to which the integrated circuit is mounted. In a first embodiment, capacitive test probes are integrated within the integrated circuit, underneath bonding pads. In a second embodiment, Hall-effect devices are integrated within the integrated circuit underneath bonding pads. In a third embodiment, an inductive loop is integrated within the integrated circuit underneath bonding pads. In a fourth embodiment, an IC package assembly includes an internal capacitive test probe for electrical continuity testing. An internal shield may also be used as a capacitive test probe. In a fifth embodiment, an IC package assembly includes an inductive loop within the package for electrical continuity testing.

Abstract: The present invention is an improved printed circuit board test system in which test probes are positioned to electronically engage a selected device or printed circuit board section on a printed circuit board for testing the printed circuit board for manufacturing defects. The printed circuit board test system uses a bed-of-nails test fixture to ground and excite predetermined sites on a first side of the printed circuit board and a robot to mechanically position test probe(s) at selected test sites on a second side of the printed circuit board. A controller is used to control the movement of the robotic tester and the selection of spring probes in the bed-of-nails fixture to be exited, grounded or measured.

Abstract: The invention is a capacitively coupled probe which can be used for non-contact acquisition of both analog and digital signals. The probe includes a shielded probe tip, a probe body which is mechanically coupled to the probe tip, and an amplifier circuit disposed within the probe body. The amplifier circuit receives a capacitively sensed signal from the probe tip and produces an amplified signal in response thereto. The amplifier has a large bandwidth to accommodate high-frequency digital signals. Further, the amplifier has a very low input capacitance and a high input resistance to reduce signal attenuation and loading of the circuit being probed. The amplifier circuit is disposed in the probe body closely adjacent to the probe tip in order to reduce stray and distributed capacitances. A reconstruction circuit reconstructs digital signals from the amplified capacitively sensed signal.

Abstract: An apparatus and a method is provided for verifying electrical coupling between a first contact point of an electrical device on a circuit board and a first connection pin, on a board tester. Within the tester, a JK flip-flop is electrically coupled to the first connection pin through an amplifier. A Q output of the JK flip-flop is initialized to a logic 0. An electrical probe with an electrical voltage is stroked across the first contact point and any other contact points on the circuit. If the first contact point is electrically coupled to the first connection pin, a logic 1 will be held on the Q output of the JK flip-flop. If there is no electrical coupling, then a logic 0 will be held on the Q output. By reinitializing the JK flip-flop and electrically coupling it to another connection pin, electrical coupling between another contact point and another connection pin may be tested.