Patent ID: 6731104
Filing Date: 2004-05-04
Classification: G01R

Abstract:
A measurement probing system having electrical over stress and electrostatic discharge protection for input circuitry of the measurement test instrument comprising:a measurement probe having a housing, a spring loaded coaxial probe assembly and a pressure sensor with the spring loaded coaxial probe assembly disposed within an internal cavity formed in the housing and having a semi-rigid coaxial cable that includes a central signal conductor and an outer shielding conductor with one end of the semi-rigid coaxial cable formed as a probing tip extending from one end of the housing and the other end receiving a coaxial connector extending from the other end of the housing, and a compression spring positioned on the semi-rigid coaxial cable, and the pressure sensor having first and second electrically conductive contacts with the first electrically conductive contact secured and electrically coupled to the outer shielding conductor of the semi-rigid coaxial cable and the second electrically conductive contact secured to the housing with the housing movable from a first position to a second position relative to the spring loaded coaxial probe assembly from pressure applied to the probing tip of the measurement probe in contact with a device under test; and a control module mounted in and electrically coupled to the measurement test instrument having a plurality of coaxial connectors with each coaxial connector having a signal conductor, the signal conductor of a first of the coaxial connector coupled via a coaxial cable to the central signal conductor of the semi-rigid coaxial cable, the signal conductor of a second coaxial connector coupled via a coaxial cable to the input circuitry of the measurement test instrument and the signal conductor of a third coaxial connector coupled via a termination resistor to electrical ground, and an input signal connector having at least a first electrical contact with the electrical contact electrically coupled by an electrical conductor to the second electrically conductive contact of the pressure sensor, the electrical contact of the input connector and the signal conductors of the coaxial connectors coupled to control circuitry for selectively coupling the probing tip of the semi-rigid coaxial cable to electrical ground via the termination resistor when the housing is in the first position and the control circuitry responsive to at least an activation signal generated by the first and second electrically conductive contacts of the pressure sensor contacting each other by movement of the housing to the second position to couple the probing tip to the input circuitry of the measurement test instrument.