1. Field of the Invention
The present invention relates to connectors for connecting circuit boards. More particularly, the present invention relates to apparatus and methods for detecting defects of connectors on circuit boards.
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2. Description of Related Art
Most computer systems include a connection structure for connecting printed circuit boards of the computer system together (e.g., central process unit boards, memory boards, etc.). One such connection structure includes a circuit board that serves as a centerplane. The centerplane (or backplane) has a set of centerplane connectors mounted to the centerplane. For such structure, the computer system also includes another circuit board called a daughter card that has card connectors that mate with the centerplane connectors. That is, the centerplane connectors and the card connectors typically include corresponding sets of contacts, respectively. For example, pins and pin-receiving sockets, which are configured to make electrical contact with each other when the centerplane connectors and the card connectors mate.
Installation of a daughter card into a computer system typically involves a user sliding the daughter card into an opening of a card cage of the connection structure. The centerplane typically resides the rear end of the card cage, or in the middle of the card cage if the card cage is configured to receive daughter cards through both ends. As the daughter card slides within the card cage, card connectors along the edge of the daughter card eventually engage centerplane connectors mounted to the centerplane at the rear or in the middle of the card cage. After the card connectors make electrical contact with the centerplane connectors, the user continues to slide the daughter card further into the card cage until the daughter card moves into a fully-seated position within the card cage. The user can repeat this installation process for other daughter cards as well.
To avoid damage to the daughter card and/or the centerplane, a detailed inspection of the centerplane connectors is required before inserting the card connectors into the centerplane connectors. The centerplane connectors should be inspected for mechanical defects such as bent and/or damaged pins on the centerplane connectors. The detected defects need to be remedied prior to insertion of the daughter card or the defects may spread into other connectors and on to the daughter card. However, because of the larger number of relatively small contacts on each of the centerplane connectors (e.g., a central processing unit (CPU) connector may have 840 pins, a repeater board (RP) may have 1400 pins, an input/output (I/O) may have 560 pins), the prior arts were unable to reliably spot damages on the centerplane connectors.
Accordingly, there is a need to provide apparatus and methods that reliably detect defects on the centerplane connectors. That is, it would be desirable to provide an inspection system that can reliably spot damages on centerplane connectors having a larger number of relatively small contacts.