Test contact connection checking method and circuit
Patent 5886530 Issued on March 23, 1999. Estimated Expiration Date: 
August 15, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
August 15, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3822398 Analyzing electrical circuit boards Automatic test equipment test probe contact isolation detection apparatus and method Self-checking ohmmeter that checks for contact resistance of its probes Self-checking ohmmeter that checks for contact resistance of its probes Patent #: 4954782 InventorsAssigneeApplicationNo. 911781 filed on 08/15/1997US Classes:324/611, Including a remote type circuit324/421, To evaluate contact resistance324/538, Electrical connectors324/756Contact confirmationExaminersPrimary: Do, DiepAttorney, Agent or FirmInternational ClassesG01R 027/14G01R 031/04 AbstractA contact resistance check circuit and method for verifying that a sufficient electrical connection is established between a source and a sense lead of a Kelvin connection. The circuit includes a microprocessor for driving a transformer that is connected to the source/sense probe (i.e., contact resistance) with an input pulse. The input pulse is altered in relation to the magnitude of the contact resistance to produce a check pulse. A comparator is used to compare the check pulse with a threshold voltage and for generating a fault indication signal. A flip flop then stores the fault indication signal so that the fault indication signal may be monitored by the microprocessor.Field of SearchTo evaluate contact resistanceCalibration With auxiliary means to condition stimulus/response signals For sensing Including a remote type circuit With a probe structure With ratio determination With comparison or difference circuit With probe elements Contact confirmation With voltage or current signal evaluation Including a particular probing technique (e.g., four point probe) Of individual circuit component or element Electrical connectors Reed switch | |
