Multipin Connector Research Articles

Generalized analytical formulation for de‐embedding of multiport devices based on known fixtures

The de-embedding is a technique used in radio frequency and signal integrity measurements to extract the scattering (S)-parameters of the device under test (DUT) from the measured data of a global assembly and based on known S-parameters of the left and right test fixtures; thus, it removes the impact of the text fixtures used for the connection of the DUT to the instrumentation. Once the S-parameters are measured, the de-embedding is performed by a multistep approach involving the bidirectional transformation of the S-parameters into the corresponding transfer scattering (T)-parameters. The latter approach is well established for two- and four-port networks and has been recently expanded to the multiport case. This work proposes an alternative analytical formulation to de-embed a multiport device, knowing in advance only the S-parameters of the global multiport assembly and those of the test fixtures. The proposed method does not involve the S-to-T conversion and it requires only the algebraic manipulation of the S-parameter matrix elements; its practical implementation is very well fitted especially for multiport cases, and it is very fast in calculating the de-embedded DUT S-parameters for large port numbers. The results of the proposed formulation, applied to the case of a multipin high-speed connector, are compared with those obtained by measurement and simulations. Their accuracy is shown and discussed to demonstrate the validity of the proposed approach.

Screening of multi-pin connectors — Suggested measuring techniques

The measurement of transfer impedance as a guide to the screening effectiveness of coaxial cables and connectors is well established, but only recently has a serious effort been made to extend the technique to multi-pin connectors used at frequencies up to 1 GHz. Among the many connectors in common use, the D-connector is one family whose widespread use keeps them inexpensive. This paper is written round testing of D-connectors, though its conclusions are applicable to most ranges of multi-pin connectors used in the digital instrument industry. Quite apart from the cost of components to be tested, if adequate screening is needed, it is important that the means of assessing this should not be costly. The test method described here is being discussed and modified by the Working Group of IEC Technical Committee 46 and, to cover the frequency range deemed necessary, uses test equipment which might be thought expensive, though the test itself is simple. Based on the development of this test, which can be used to show the fundamental problems in using such connectors at high frequencies, the paper goes on to outline a test procedure which can use commonly available and inexpensive laboratory equipment, is economical in test time, and yet can be shown to fulfil most of the needs of the connector maker and user.

A SPICE model for angled multipin connectors

A SPICE model for angled multipin connectors

High-speed data transmission in a rack system with coaxial board connectors

The speed at which data can be transmitted in communication rack systems is limited by crosstalk simultaneous switching noise in the data signal. We experimentally evaluated the relationship between this noise and transmission speed. The experimental rack system had 24 independently driven channels consisting of a driver-printed board assembly (PBA), connector, back panel (BP), connector, and receiver-PBA. The drivers are 210-270 ps edge rate ECL devices. The rack structure allowed the line length on the panel to be changed from 15 cm to 45 cm by changing the slots of the driver and receiver cards. A newly developed small, high-density multicoaxial package connector was used, and an error rate detector was used to determine the error-free transmission speed at various receiver reference voltages. For a 60-cm line, the maximum speed of the rack system was 622 Mb/s, more than four times that achieved when using a conventional multipin connector.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The Construction of Endocardial Balloon Arrays for Cardiac Mapping

The advent of multichannel recording systems has enabled clinical mapping to be performed on a beat-by-beat basis using multi-electrode arrays. Surgical ablation of ventricular arrhythmias generally requires endocardial mapping. Clinical usage has indicated that an inflatable balloon array is the most practical design and can obviate the need for ventriculotomy by a transatrial introduction in the deflated state. Successful experience with the left ventricular balloon led to the development of a right ventricular balloon array suitably configured to extend into the outflow tract. Custom moulds are used to create an appropriate balloon from liquid latex. Nylon cloth is cut from a cardboard pattern to fashion a stretchable sock to envelope the balloon. Electrodes are formed by stitching 2-mm silver beads to the balloon sock in a preconfigured pattern. Teflon-coated 31 G multi-strand stainless-steel wires 130 mm in length connect the electrode beads by solder to the multipin connectors for easy hookup to the amplifier inputs. Tygon tubing 0.53 cm in diameter fitted to the balloon allows inflation and pressure monitoring. This basic design has been successfully implemented for the last 6 years.

Ultrasonic transducer method and apparatus

An ultrasonic transducer assembly comprising an injection-molded body member, a pair of piezoelectric ceramic members and a multi-pin connector is described. The piezoelectric ceramic members are electrically connected to the multi-pin connector by means of thin metallic ribbons. When assembled, the transducer assembly is detachably inserted in recesses provided therefor in the end of a hand-held probe.

Insertion force reduction in multipin connectors with various tip shapes

AbstractTo decrease the insertion force of multipin electrical connectors in communication equipment, the tip shape of the male connector was analyzed theoretically, and a model experiment of contact insertion was carried out. From comparison of the theoretical and experimental results, the following results were obtained: (1) if the friction between contacts in connector insertion is not taken into account, a root curve shape is the optimum tip shape; and (2) the insertion experiment using a model for a male connector tip agrees with the theoretical result. As a result, it was shown that the friction between the contacts has an important role, and that to reduce the insertion force, the shape of the tip must be designed with friction taken into account.From the foregoing results, the connector tip was designed to make the insertion force constant regardless of friction. By investigating the force reduction using a multipin connector of about 200 pins, the evaluation based on the tip shape was found to be valid.

High-Density Multipin Connector for High-Speed Pulse Propagation

A Procedure for designing connectors suitable for gigabit per second (Gbit/s) rate pulse propagation is presented. A design chart for a multipin connector satisfying both electrical and mechanical requirements is obtained. The design procedure is as follows. First, the effect of varying the arrangement of ground contact springs on characteristic impedance is investigated using the finite-element method. Next, the effect of varying contact spring size and contact spring pitch is analyzed with respect to characteristic impedance and crosstalk. Finally, a design chart is constructed for the multipin connector by combining the mechanical characteristics of the contact springs with the aforementioned electrical characteristics. Based on the resulting design chart, a prototype multipin connector for a pin grid array is fabricated. The empirically derived electrical characteristics of the prototype connector are in good agreement with those predicted analytically.

The Lightning Arrestor Connector

A multipin connector has been modified to include lightning arresting features. A dielectric stimulated arc is used for rapid electrical, breakdown in the connector prior to any damage to downstream components. This report reviews the connector design basis and concept, and summarizes the electrical test results obtained during development and production. Electrical testing included insulation resistance, high voltage rise rate (to 500 kV/µs) tests and simulated lightning (over 200 kA) exposures. The lightning arrestor connector has been effective under all tests maintaining an insulation resistance over 100 M, and shorting fast rise lightning induced voltages to about 1000 V. A final test of a missile system showed the lightning arrestor connector effectively protected missile components against simulated lightning.

The Lightning Arrestor-Connector Concept: Description and Data

Experimental and theoretical data show that a new compact lightning arrestor can be incorporated into a multipin connector housing to protect components in missile, aircraft, and ground systems from lightning energy. This energy is sometimes transmitted into component compartments causing component burnout, ignition of explosives, and circuit malfunctions. By properly incorporating the lightning arrestor-connector, these effects can be minimized or eliminated. The lightning arrestor-connector concept has been analyzed, and prototype devices have been tested extensively at Sandia Laboratories. Production for use in several missile systems has begun. The design and initial development of the device is described along with data demonstrating the device behavior under simulated lightning tests.