Patent Application
20150041212
The present invention relates generally to the data processing field, and more particularly, relates to a solder tail connector and method for implementing production of solder tail extender connectors from compliant pin connectors.
New connector systems such as Impact™ connector systems are often offered with compliant pins but not solder tail versions. Solder tail versions are often used in flex cross sections. Providing tooling for solder tail versions of compliant pin connectors is expensive and solder tail lengths are limited.
Complaint pin versions are often used in thick rigid cards to be able to meet the electrical stub reduction requirements as signal speeds continue to increase.
Flex cross sections can be converted to rigid flex by adding rigid materials so the compliant pin can reside in a rigid portion of the cross section. This arrangement adds cost, complexity to the flex design, and signal integrity concerns due to material changes within layers and increased stub length.
Paste in hole or wave solder with oversized vias can be used with existing compliant pin connectors, but compliant pin lengths are short so pins may not extend through the cross section. As such, this construction does not allow for clear visual inspection of solder joints, and as a result requires x-ray inspection. Oversized vias have adverse cost, raw substrate manufacturability, reliability, and signal integrity (SI) impacts.
A need exists for methods to enable effective use of compliant pin connectors for solder tail applications.
Principal aspects of the present invention are to provide a solder tail extender connector and method for implementing production of solder tail connectors from compliant pin connectors. Other important aspects of the present invention are to provide such method, and solder tail extender connector substantially without negative effects and that overcome many of the disadvantages of prior art arrangements.
In brief, a solder tail extender connector and method are provided for implementing production of solder tail extender connectors from compliant pins. A forming fixture is provided to collapse compliant pins prior to soldering. The compliant pin is collapsed at or beyond the normal compliant pin low end dimensions and removed from the forming fixture. A solder tail extender optionally is added to the collapsed compliant pin, forming the solder tail extender connector.
In accordance with features of the invention, the methods convert compliant pins to solder tail extender connector without significant additional tooling expenses.
In accordance with features of the invention, the solder tail extender connector enables use with a minimum via size, improving wire-ability, raw substrate manufacturability, reliability and signal integrity performance.
In accordance with features of the invention, the compliant pin includes a selected plating or coating, and the solder tail extender includes a selected plating or coating internally and externally with the selected material to facilitate solder wicking or a selected material that will reflow during connector processing.
In accordance with features of the invention, the solder tail extender includes a selected shape, such as a cylindrical shape or split shape for insertion onto the collapsed compliant pin.
In accordance with features of the invention, the solder tail extender includes a selected solder tail length to form the solder tail extender connector allowing proper stick through for wave solder and visual inspection.
In accordance with features of the invention, the solder tail extender optionally includes additional holes to allow for solder entry.
The present invention together with the above and other objects and advantages may best be understood from the following detailed description of the preferred embodiments of the invention illustrated in the drawings, wherein:
In the following detailed description of embodiments of the invention, reference is made to the accompanying drawings, which illustrate example embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
In accordance with features of the invention, a solder tail extender connector and method are provided for implementing production of solder tail extender connectors from compliant pins.
In accordance with features of the invention, the method is a low cost method to modify compliant pins for use in solder tail applications. The solder tail extender connector enables a reduced required via size, improving wire-ability, raw substrate manufacturability, reliability, cost, and signal integrity (SI) performance. Also via size in flex drives channel to channel cross-talk. By collapsing the compliant pins and reducing via size, the cross-talk is minimized improving system design margin which is critical for many flex designs. The solder tail extender connector provides a customizable solder tail length that allows proper stick through for wave soldering and visual inspection.
Having reference now to the drawings, in
The forming fixture 104 includes a selected bottom edge contour 106 and a selected contoured length 108 for a specific application to collapse the compliant pin 102 before soldering. The compliant pin 102 is inserted into the forming fixture 104 as indicated by an arrow labeled A to be collapsed or formed, and then is removed the forming fixture 104. As illustrated in
The compliant pin 102 has a predefined shape 110 including a compliant section 112 having a central slot or cavity 114, a tapered end or tip 116 and an opposed base or post 118. The compliant pin 102 includes an initial diameter indicated by an arrow B1, such as 0.019″. The compliant pin 102 includes a plating or coating, such as a tin/nickel coating or a gold/nickel coating. The compliant pin 102 withstands the insertion and removal from the forming fixture 104 without compromising coating integrity.
The insertion and removal of the compliant pin 102 from the forming fixture 104 can cause wear to the compliant pin plating finish, while not exposing the undercoat of the compliant pin. The material selection and contouring selection of the forming tool enables use of existing compliant pin metallurgy without being compromised.
Referring to
Referring to
The solder tail extender 302 has a selected size and shape for a particular application, such as cylindrical or other shape, and for example, split for insertion onto the collapsed compliant pin 202. The solder tail extender 302 has a selected length for a particular application to enable proper stick through for wave solder and visual inspection. The solder tail extender 302 includes a selected plating or coating, such as a tin/nickel coating or a gold/nickel coating.
Referring to
Referring to
As indicated in a block 400, a selected forming fixture is provided for receiving and forming a compliant pin, for example as illustrated and described above with respect to
As indicated in a block 404, the collapsed compliant pin is removed from the forming fixture, such as illustrated and described above with respect to
As indicated in a block 406, the selected solder tail extender is added to the collapsed compliant pin forming the solder tail extender connector, and the solder tail extender connector is inserted into a flex via or other desired via, to then be soldered, for example, as illustrated and described with respect to
While the present invention has been described with reference to the details of the embodiments of the invention shown in the drawing, these details are not intended to limit the scope of the invention as claimed in the appended claims.
