Mechanical Supports for Surface-Mounted Leaded and Leadless Components
Original Publication Date: 1986-Nov-01
Included in the Prior Art Database: 2005-Mar-09
Surface-mounted technology uses solder joints to both complete I/O connections and provide the mechanical support necessary to hold a component on a card. Testing has shown that solder joint surface- mounted connections cannot take the loads that pin-in-hole connections can. When a surface-mounted connection is subjected to excessive loads, the solder joint will crack. The crack can disrupt I/O transmissions and cause a card to fail. Testing also shows that the eight corner leads of a surface-mounted component support the most load, and will be the first to crack, causing a card to fail. If a corner solder joint cracks, a card will fail when the corner leads of a component are functional I/O leads. In the improved arrangement, the corner leads are used for mechanical support only.