Electrical connectors – With circuit conductors and safety grounding provision
Reexamination Certificate
1999-09-30
2001-05-15
Bradley, Paula (Department: 2833)
Electrical connectors
With circuit conductors and safety grounding provision
C439S076100, C439S607070, C439S939000
Reexamination Certificate
active
06231356
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to packaged electronic assemblies, and, more particularly, to a grounding clip for computer peripheral cards.
2. Description of the Related Art
Electronic devices such as computers, laptops, personal digital assistance (PDA's), etc. utilize various types of interfaces in order to exchange data and expand their capabilities. For example, personal computers utilize parallel, serial, and bus interfaces to connect to external devices and exchange data. Bus interfaces often take the form of a slot connected to a printed circuit board that contains electrical contacts, and are sized to receive peripheral cards designed to meet specific standards. Examples of such standards include the Industry Standard Architecture (ISA), the Peripheral Component Interconnect (PCI), and the Personal Computer Memory Card International Association (PCMCIA).
The PCMCIA standard has been extensively refined to provide the requirements for accommodating a variety of device types on the basic peripheral card format. Some of the devices that can be accommodated on the PCMCIA peripheral card include random access memory (RAM), EEPROMs, hard disk drives, fax/modems, etc. PCMCIA cards are relatively small in size, hence lending to popularity for use with laptops, PDA's, etc.
Peripheral cards, such as PCMCIA cards, can be constructed in various ways. A typical PCMCIA card includes a printed circuit board (PCB) containing various types of electronic components mounted thereon. For example, various controller chips or a central processing unit (CPU) chip can be mounted on the PCB. In addition, the PCB may include integrated circuitry formed thereon as part of a fabrication process. The PCB is subsequently encased within a protective metal cover. The protective metal cover includes an edge that contains a plurality of female electrical connectors. Electronic devices that receive PCMCIA cards include corresponding male connectors that establish an electrical connection between the PCMCIA card and the electronic device. Peripheral cards such as PCI and ISA cards, however, are constructed such that only the edge connectors that will subsequently be in contact with the electronic device, are exposed.
One of the major problems encountered in manufacturing and handling peripheral cards is the build-up of electrical charges on the PCB. For example, during the manufacturing process, the peripheral card must be handled and carried on multiple occasions. During this process an electrical charge is generated and built up on the peripheral card. The amount of charge generated and built up depends on the amount of handling and the environment in which the peripheral card is handled. Consequently, a peripheral card can be packaged and sold while bearing an electrical charge thereon. When the peripheral card is inserted into the host device (i.e. the computer or PDA), the charge flows into the host device through the edge connectors. Since the edge connectors are in direct electrical communication with various components in the host device, the discharge of electrical energy from the peripheral card can cause significant damage to the circuit, which can, on occasions, lead to failure of the host device.
The discharge of electrical energy from the peripheral card to the device can be eliminated, for example, by grounding the peripheral card prior to contacting it with the device. This has been typically accomplished by providing a conductive grounding clip on the peripheral card for purposes of engaging an appropriate grounding circuit on the device. For example, the PCMCIA standard provides for grounding clips at a fixed location along the side edge of the peripheral card. Such an arrangement, however, requires additional parts and increases manufacturing costs in order to properly route the requisite number of traces to the grounding edge of the peripheral card.
Accordingly, one disadvantage associated with current peripheral cards is the inadvertent build-up of electrical charges that can potentially destroy circuitry on the host device that will receive the peripheral card. Another disadvantage associated with current peripheral cards is the extended manufacturing steps traditionally required to properly provide a grounding point.
DISCLOSURE OF THE INVENTION
An advantage of the present invention is the ability to easily discharge a peripheral card prior to electrically contacting the host device in which it will be inserted.
This and other advantages are achieved by present invention wherein a grounding clip contacts a peripheral card prior to electrical connection with a host device in order to direct any charge that has been built up on the peripheral card to a grounding point.
In accordance with one aspect of the invention, a grounding clip for a peripheral card comprises a base and at least one plurality of finger. The base includes a contact surface and contains an aperture that is defined by an internal length portion and an internal width portion thereof. Further, the aperture is appropriately sized and configured to receive the particular peripheral card that must be discharged by the grounding clip. The at least one finger extends from one of the internal length portions of the base. Each finger includes a discharge surface for contacting and grounding the peripheral card. Further, according to one embodiment of the invention, the plurality of fingers can be paired and disposed in registry along opposing internal length portions of the base.
The present invention advantageously provides the ability to discharge a peripheral card prior to connection with the host device. This is accomplished by using the discharge surface of the fingers to direct any charge that has been built up on the peripheral card to a low impedance, high frequency grounding point. Hence, damage to the circuitry of the host device, as a result of electrical discharge from the peripheral card, is eliminated.
Additional advantages and novel features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the present invention. The embodiments shown and described provide an illustration of the best mode contemplated for carrying out the present invention. The advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
REFERENCES:
patent: 4738637 (1988-04-01), Asick et al.
patent: 5893766 (1999-04-01), Bellas et al.
patent: 5940275 (1999-08-01), Laity
patent: 6008994 (1999-12-01), Bates
Eastman Scott
Korzik Jim
Kozak Frederic
Stutts Jim
Bradley Paula
Cisco Technology Inc.
Hickman Palermo & Truong & Becker LLP
Leon Edwin A.
Palermo Christopher J.
LandOfFree
Grounding clip for computer peripheral cards does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Grounding clip for computer peripheral cards, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grounding clip for computer peripheral cards will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2545964