Socket fixture for testing warped memory modules on a PC motherboard

A memory module test socket can accept modules with bent or warped printed-circuit boards (PCBs). A support plate is mounted above a Personal Computer (PC) motherboard by standoffs. An extender card fits through a slot in the support plate. The bottom edge of the extender card is plugged into a motherboard memory module socket on the motherboard. The top of the extender card has an extender socket that sits atop the support plate. End guides are mounted to the support plate and clamp down the extender socket. Funnel guides formed in the end guides have a funnel shape to guide ends of a memory module for better alignment when inserted into the extender socket. A pusher plate with a triangular guide or a perpendicular rod applies a perpendicular force on the middle of a warped memory module to align the middle to the extender socket during insertion.

FIELD OF THE INVENTION

This invention relates to memory module test sockets, and more particularly to memory-module test sockets for testing warped modules.

BACKGROUND OF THE INVENTION

Memory modules such as Dual-Inline Memory Modules (DIMMs) are widely used in personal computer (PC) and other systems. Robotic arms may pick and place memory modules into special test sockets. The test sockets may be mounted on an inexpensive PC motherboard rather than on an expensive electronic test machine such as automated-test-equipment (ATE).

Test sockets used in memory module production are typically more durable that ordinary memory modules sockets on an inexpensive PC motherboard. Special attention may be given to providing a smooth insertion of the module into the test socket so that the module is not nicked or otherwise damaged during testing.

While the test socket is usually manufactured to a significant degree of precision, the memory modules may not be as precise. Sometimes the small printed-circuit board (PCB) that the memory chips are soldered to is not exactly planar. A certain amount of bend or warpage may exist. Such warped memory modules may be manually inserted into memory module sockets on a PC motherboard, since the human hand can bend the module board slightly to make it fit into the socket. However, during testing, a robotic arm often is used for module insertion. The robotic arm very precisely moves and places the module into the socket, and is not as adaptive as the human hand. When a robotic arm inserts a warped module into a test socket, often the robotic arm is not able to insert the module properly. The module board's warpage may get caught on part of the test socket and hinder insertion.

What is desired is a memory module test socket and robotic system that can test warped memory modules. A test socket that can accept bent modules is desirable, especially for use with a robotic arm.

DETAILED DESCRIPTION

FIG. 1is a top or overhead view of a memory module test socket. Memory module10is inserted into the test socket as the module-under-test (MUT). The ends of memory module10fit into funnel guides22formed in end guides20. The funnel or conical shape of funnel guides22directs the lower edge of memory module10into better alignment with extender socket30, which has metal contacts that make electrical contact with metal contact pads on the bottom edge of memory module10. Funnel guides22allow for a less accurate placement of memory module10in the test socket, which can reduce the cost of the robotic arm or allow for a faster operation, thus reducing test costs.

FIG. 2is a side view of the memory module test socket. Memory chips12may be dynamic-random-access memory (DRAM) chips that are connected to metal contact pads arrayed along the bottom edge of memory module10that make electrical contact with metal springs or contacts inside extender socket30when fully inserted. Funnel guides22are funnel-shaped forms or cutouts of end guides20that guide the ends of memory module10into alignment with extender socket30.

Extender card24is a small printed-circuit board (PCB) that has extender socket30mounted to the top and has metal contact pads on the bottom edge that fits into motherboard memory module socket26. Motherboard memory module socket26can be the standard memory module sockets on the component side of a PC motherboard, or could be replaced with better sockets. Motherboard memory module socket26could also be located on the reverse or solder side of motherboard28, but the added height provided by extender card24provides clearance over components on motherboard28.

Extender card24has metal traces that connect metal contacts on the lower edge with spring contacts in extender socket30on the top edge. In some embodiments, the corresponding lower and top edge contacts are connected together, although some functionality can be added to extender card24such as swapping or crossing over address or data lines.

Support plate40can be a rigid plastic plate that has a slot that extender card24fits through. Extender socket30and end guides20can be supported by the top surface of support plate40. End guides20can be mounted to extender socket30or to support plate40or to both by screws, bolts, clamps, or other mounting methods. For example, pins, bolts, or screws42can secure end guides20to support plate40while extender socket30is clamped down to support plate40by a step on the bottom of end guides20.

Standoff43is attached to support plate40by pins, bolts, or screws44, and to motherboard28by pins, bolts, or screws46. There are typically several standoffs43located on several sides of extender socket30rather than just one as shown.

FIG. 3is an end view of the memory module test socket. Standoff43is attached to motherboard28by pins, bolts, or screws46and to support plate40by pins, bolts, or screws44. Extender card24has lower contact pads that fit into motherboard memory module socket26and has extender socket30that receives metal contacts on memory module10.

End guides20are mounted to support plate40by pins, bolts, or screws42. End guides20surround and clamp down the ends of extender socket30to support plate40. Funnel guides22are formed inside end guides20and guide the edges of memory module10into better alignment with extender socket30as memory module10is pushed further downward.

FIG. 4highlights better alignment of a mis-aligned memory module inserted into the test socket. Memory module10is placed off-center relative to extender socket30during insertion. However, funnel guides22catch one of the ends of memory module10and guide the module to the right as it falls or is pushed downward. Notches23on the edges of memory module10can accept a levered handle or a spring clip (not shown) in end guides20to secure memory module10into the test socket once inserted.

FIG. 5highlights final alignment of a mis-aligned memory module inserted into the test socket. Once the lower edge of memory module10reaches the top of extender socket30, memory module10has been re-aligned by funnel guides22. As memory module10is pushed further downward, the lower edge of memory module10is forced into extender socket30with a proper alignment of metal contact pads so that electrical contact is made.

FIG. 6shows a pusher plate being used to insert a warped memory module. Pusher plate70has a triangular guide that pushes downward upon the top edge of memory module10during insertion. If there is a slight bend or warp to memory module10, the triangular guide of pusher plate70can apply a perpendicular force (to the left or right in the end view ofFIG. 6) to flex memory module10into a flatter position.

Pusher plate70and its triangular guide can extend the whole length of memory module10, or could extend just near the middle of memory module10.

FIG. 7shows a warped memory module being inserted into the test socket. Memory module10has a bend or warp on its PCB causing the middle of memory module10to be mis-aligned to slot74in extender socket30when the ends of memory module10are guided into alignment with extender socket30by funnel guides22.

FIG. 8shows a perpendicular rod that pushes the middle of a warped memory module into alignment with the test socket. Perpendicular rod76applies a perpendicular force to the middle of memory module10, bending the module PCB inward to better align with slot74. Opposing perpendicular rod78applies an opposing perpendicular force when memory module10is warped in the other direction from that shown inFIG. 8. Only one of perpendicular rod76and opposing perpendicular rod78is activated at a time, although in some embodiments both rods76,78could be activated at the same time to pinch the middle of memory module10into alignment with slot74in extender socket30. A soft end or tip could be provided to rods76,78where they make contact with memory module10to prevent scratching or damage to memory module10.

Perpendicular rods76,78may be mounted with servos77or other motor drives onto support plate40, or may be part of the robotic arm assembly.

Alternate Embodiments

Several other embodiments are contemplated by the inventors. For example, ejectors may be added to extender socket30to aid in removal of memory module10after testing is completed. Sliding levered handles may be added to extender socket30or to end guides20to provide leverage when inserting and removing memory modules. See for instance U.S. Pat. No. 6,981,886 for a mechanism of the sliding levered handle. The levered handles can have an end that engages notches23ofFIG. 4. A robotic arm may activate the ejectors or levered handles, or an actuator, servo, or other motor or motion device or mechanism may be used to move the ejector or handles. The sliding levered handles may also be mounted to the robotic arm directly. Alternately, the notch engager for notches23may also be made a part of the robotic arm.

More than one test socket may be placed on the same support plate40, and motherboard28may have several motherboard memory module sockets26. Other functions such as for error-correction code (ECC) testing may be added to extender card24. See for instance U.S. Pat. No. 7,272,774 for ECC testing using an extender card.

Support plate40may have a variety of shapes and have various cutouts and slots74to fit extender card24and components on motherboard28that protrude above support plate40. Support plate40may be made from a thicker, more insulating material or fiberglass to improve the rigidity.

More than one memory module socket may be used on support plate40. Each levered handle could engage just one notch on one memory module, or a notch engager could have an elongated depth so that notches on two or more memory modules could be engaged simultaneously.

Various other enhancements can be made, such as locks, stops, or holding mechanisms for holding levered handle or memory module10in its position. The levered handles could be attached to a base that is attached directly to a memory module socket, without using a support plate40.

Positions such as up, down, etc. are relative and may be interchangeable, such as when the socket is transformed or re-positioned. Support plate40, standoffs, and extender socket30can be made from a variety of materials such as metal or rigid plastic.

Extender socket30could be mounted to support plate40or to end guides20in a variety of other ways, such as by adhesive, clamps, pins, clips, screws, or bolts in various locations, etc. The shape and size of slot74can vary, such as one or more long rectangles or ovals to closely fit one or more extender card24, or other shapes.

The background of the invention section may contain background information about the problem or environment of the invention rather than describe prior art by others. Thus inclusion of material in the background section is not an admission of prior art by the Applicant.

Any methods or processes described herein are machine-implemented or computer-implemented and are intended to be performed by machine, computer, or other device and are not intended to be performed solely by humans without such machine assistance. Tangible results generated may include reports or other machine-generated displays on display devices such as computer monitors, projection devices, audio-generating devices, and related media devices, and may include hardcopy printouts that are also machine-generated. Computer control of other machines is another tangible result.