Carrier and socket technology for high pin count QFP packages

Abstract

The carrier and socket technology for high pin count Quad Flat Pack (QFP) packages is a set of three components that can be used in various combinations, that allow for easier manipulation of fine pitch, (fine pitch defined as packages having a lead tip to lead tip spacing of 0.65 millimeters or less), QFP between various shipping, test, programming, and prototype environments. The three components are the small outline carrier, surface mountable development socket, and through hole mountable programming socket. The carrier is designed to protect the leads of the QFP from deformation, while allowing the leads to make electrical connection with the contacts of the two different sockets. The development socket is surface mountable with a footprint that is identical to the naked QFP housed within the carrier. The programming socket is a through hole mountable, clam-shell socket, which accepts the same carrier as the development socket. The carrier and socket technology was developed primarily to assist in the development and prototyping of re-configurable QFP devices. Specifically, those QFP devices that need to be placed in a different electrical environment to be re-configured, than the electrical environment the device will be in, once it has been configured to the users satisfaction. >