The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1998
Filed:
Aug. 19, 1996
Brian Keith Lucas, Avon, GB;
Proteus Corporation, Denver, CO (US);
Abstract
The printed circuit board fault injector circuit uses an automated fixture to enable a robot arm mechanism to position a probe at a designated test node on the printed circuit board under test and apply a fault signal thereto. The test apparatus ensures that the designated node is in contact with the fault injector probe and controllably applies a voltage and/or current signal of selected magnitude to the test node to typically create a stuck-at-one or a stuck-at-zero fault or any other definable condition. The fault injector probe produces a stuck-at-zero fault that is not subject to spurious high frequency harmonics by extending the dynamic range of the fault injector circuit to apply a negative voltage to the test node to rob the output stage of the logic circuit that drives the test node of all drive current, thereby forcing a solid stuck-at-zero condition. Additional monitoring circuitry is provided to detect excessive current drain from the fault injector circuit into the test node to avoid causing damage to the printed circuit board under test.