Texas Instruments Corporation

Angus W Hightower

John Walter Orcutt

Reginald W Smith

Dennis D Davis

David R Kee

Richard E Johnson

A lead from 10 carries an integrated circuit on a die support pad 14. The lead frame has a dam bar including a transverse portion that extends between adjacent leads (20) for limiting mold flash. The dam bar transverse portion 26 is entirely severed from the adjacent leads for final removal by a metal punch 33 along with the supporting web 16.

Method of making an integrated circuit using a pre-served dam bar to

An integrated circuit package having a large number of external connections is assembled using two lead frames stacked one atop the other. The lead frames have complementary lead patterns which interdigitate to provide a very close lead spacing at the periphery of a semiconductor chip on which a complex integrated circuit is fabricated.

Stacked interdigitated lead frame assembly

A carrier having a plurality of leads extending from the lateral sides thereof. The leads extending along the lateral side and over protuberances into depressions in the bottom of the carrier. Each of the depressions is separated by ribs from the other depressions. The ends of the leads disposed in the depressions are prevented from substantial movement by the rib to prevent contact with adjacent leads. At least some of the leads are provided with holes disposed adjacent to the exit of the leads from the enclosure of the carrier. The holes in the leads allow the leads greater flexibility at their portions close to the entrance of the leads into the enclosure. The leads are tapered along their length toward the protuberances. Further, the leads are separated by a width along the lateral side which is within the range of slightly greater than the width of the leads to less than the width of the leads to prevent nesting.

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Richardson, TX, United States of America

Angus W Hightower