Systems and methods for providing a resistor-pin assembly

#This invention relates generally to instrumentation used in the testing and measuring of electrical signals. More specifically, the invention relates to systems and methods that use voltage probes for making electrical connections between signals under test and the inputs of test equipment.

#Wide bandwidth voltage probes can be categorized into three general types: low-impedance passive probes, active probes, and high-impedance passive probes. The most commonly used type of wide bandwidth voltage probe is the high-impedance passive probe. This probe type is rugged, reliable, simple to use, and inexpensive. For relatively low-frequency signals, including DC signals, these probes can present a very high-impedance load to the circuit under test. However, connecting this probe to a test signal can attenuate its higher frequency components thereby distorting it.

#The simplest type of probe for high-bandwidth signals is the low-impedance, or low-Z, probe. This type of probe typically employs a 50 ohm coaxial cable that is connected to a 50 ohm input of the test instrument. The low-impedance passive probe type is rugged, reliable, and relatively inexpensive. It is also capable of very high bandwidth (well into the GHz frequency range). A drawback of this probe type is the significant load that it introduces to the circuit under test. This load can significantly alter the test signal, perhaps enough to cause a malfunction in the circuit being tested. Consequently, the low-impedance probe type is normally used only when a very high bandwidth is required and only for circuits that can tolerate the significant resistive load of these probes.

#The invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views.

#FIG. 1 is a schematic diagram depicting a pin in accordance with one embodiment of the invention.

#FIG. 2 is a schematic diagram depicting a resistor-pin assembly comprising the pin shown in FIG. 1.

#One way to improve the bandwidth capability of a voltage probe is to place a resistor within the voltage probe in such a way that it is very close to (e.g., within about 1 mm from) a test point that is contacted by the voltage probe. This may involve making a tiny pin-head for contacting the test point, attaching the tiny pinhead to one end of a resistor, and connecting the other end of the resistor to another voltage probe component. However, such a tiny pin-head would be about the size of a grain of sand and would therefore be very difficult to properly handle, even with a pair of tweezers. Therefore, an embodiment of the invention provides a pin having a pin-head that can be easily separated from the remainder of the pin during the manufacturing of a resistor-pin assembly. In this manner, the pin may be used to easily handle and manipulate the pin-head during the manufacturing process. Furthermore, the shaft and base of the pin may be configured to form a component of the resistor-pin assembly, thereby further reducing manufacturing costs.

#Select embodiments of the present invention now will be described with reference to the accompanying drawings. These embodiments are examples, among others, of systems and methods of the present invention. Therefore, the present invention, which may be embodied in many different forms, should not be construed as limited to the embodiments set forth herein.

#FIG. 1 is a schematic diagram depicting a pin 100. The pin 100 may be used to form a pin assembly that can be incorporated into a voltage probe. The pin 100 is preferably only a few millimeters (mm) in length. In one embodiment, for example, among others, the pin is about 7 mm long. The exact length of a pin 100 may be determined based on a desired implementation.