Certain embodiments of the present invention generally relate to a contact configured to deflect across a defined vertical range while electrically connecting a circuit board to a processor.
Many large electronic devices, such as computers, use sockets to connect different electronic components. For example, pin grid array (PGA) sockets are used to electrically connect electronic packages, such as processors, to printed circuit boards. PGA sockets facilitate electrical communication between a large number of pins on the processor and contacts on the circuit board. PGA sockets may utilize a cover that is slidably movable on a base between open and closed positions. The sliding movement may be actuated, for example, by a lever. The cover has a hole array configured to match a pin array on the processor. Similarly, the base has an array of pin receiving chambers configured to accept the pin array of the processor. The processor is mated to the socket by first placing the processor such that its pins slide into the holes of the cover. With the cover in the open position, the processor pins pass through the holes of the cover into the pin receiving chambers of the base, but are not electrically connected to the pin receiving chambers of the base.
When the cover is slid to the closed position, the processor pins electrically connect to contacts in the pin receiving chambers in the base. The contacts have fingers that flexible receive the processor pins therebetween. This PGA base and cover arrangement, however, requires use of a mechanism, such as a lever assembly, thereby introducing excess parts and manufacturing cost. The PGA base and cover arrangement also requires additional space for the contacts as the fingers on the contacts must flex outward away from each other to receive the processor pins. These drawbacks are especially troublesome in applications where space is at a premium, such as on motherboards for desktop and laptop computers.
Consequently, land grid array (LGA) sockets have been developed which require only vertical compression to allow a processor and circuit board to electrically communicate. The LGA sockets do not require the lever mechanism, and can be used in applications with more stringent space requirements. LGA sockets, however, require a vertical compression force to be continuously applied to the processor to maintain proper communication between the processor and the circuit board.
One LGA socket has been proposed in an application, entitled “Surface Mount Technology Land Grid Array Socket,” filed on Aug. 5, 2002, and afforded Ser. No. 10/212,414. FIGS. 1 and 2 illustrate the above-noted electrical system 10 including a surface mount land grid array (LGA) socket 11. The electrical system 10 also includes a circuit board 12 to which the socket 11 is mounted and a processor 18 mounted to the socket 11. The socket 11 includes a frame 14, a housing 16 (see FIG. 2), and bias spring arms 20. The frame 14 includes an array of holes 86 therein that hold socket contacts in a pattern that corresponds to a pattern of contacts provided on the bottom of the processor 18. The bias spring arms 20 locate and position the processor 18 with respect to the socket 11 such that the processor contacts align and engage socket contacts to facilitate electrical communication between the processor 18 and the circuit board 12. When the housing 16 is positioned in the frame 14 and the processor 18 is positioned on the housing 16, the processor and socket contacts are placed under a desired vertical load between the circuit board and the processor.
However, existing LGA socket contacts have experienced certain limitations, such as an unduly limited range of deflection. More specifically, after the processor is positioned on top of the socket contact, the processor applies a normal vertical force that deflects the socket contact between first and second contact positions. The range of deflection determines certain tolerances of the individual components, such as the socket, processor, and circuit board. Conventional LGA socket contacts have an unduly limited range of deflection which places undesirably narrow limits on the component tolerances. Additionally, conventional socket contacts may not return to their unbiased first position upon removal of the processor while affording the desired deflection range.
A need exists for an LGA socket contact that addresses the above noted problems and others experienced heretofore.