Abstract: With the present invention, a component may be identified based upon selected physical characteristics of the component. In one embodiment, a system is provided for storing information pertaining to components within a set of components. A characterization function, which is a function of relevant physical characteristics shared by each component within the set of components, is associated with the set of components. The system includes a characterization value test station and a database. The characterization value test station is used to determine the characterization values of the components pursuant to the characterization function. The database stores information that pertains to each component with the component's characterization value linked as an identifier to the information. In this manner, information pertaining to a component may be retrieved from the database based on the component's characterization value.

Abstract: The present invention provides a method for identifying components based upon selected physical characteristics. Initially, a characterization function that will produce a unique characterization value within a set of components, is (or has been) assigned to the set of components. The characterization function is a function of at least one physical characteristic that is shared by the components within the set of components. Next, the measurable physical characteristics defined as part of the characterization function are measured by testing. A characterization value, which is calculated from the assigned characterization function, is determined for each component. Each component that is to be subsequently identified is then identified by its associated characterization value.

Abstract: An integrated circuit testing apparatus and method of testing. In a first embodiment an amplifier amplifies the difference in a reference integrated circuit (RIC) response and a device under test integrated circuit (DUTIC) response to an electrical stimulus. The electrical stimulus is provided at an input of the DUTIC and the RIC by a stimulus circuit. A analog comparator determines when the amplified differences exceeds an adjustable threshold value. The sensitivity of the comparator is adjustable and the desired threshold value is adjusted before testing begins. If the amplified difference exceeds the threshold value of the comparator an error signal is generated. The apparatus of the invention includes a presetable counter which generates a device fail signal if a predetermined number of error signals are generated by the comparator. An initialization circuit loads a selectable value into the counter to provide a variable number of allowable errors before a DUTIC fails the test.