High frequency microelectronic circuit enclosure

• US 5,541,565 A
• Filed: 05/22/1995
• Issued: 07/30/1996
• Est. Priority Date: 05/22/1995
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Corporation
• Original Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Edwards, Jeffrey M., Smith, Duncan M., Dowsing, John E. III
• Primary Examiner(s): GENSLER, PAUL L
• Application Number:
  US08/445,965
• Time in Patent Office: 435 Days
• Field of Search: 333/34, 333/246, 333/247, 257/664, 257/666, 257/728
• US Class Current: 333/34
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/1423 Monolithic Microwave Integrated Circuit [MMIC]
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 Multilayer substrate
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/30111 matching
• CPC Class Codes: H05K 1/0237 : High frequency adaptations H05K1/0216 takes precedence
• CPC Class Codes: H05K 3/3421 : Leaded components
• CPC Class Codes: H05K 3/3426 : characterised by the leads
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

An enclosure assembly for a high frequency integrated circuit. The enclosure assembly includes a plurality of lead terminals that are part of a lead frame. The lead terminals are connected to electrical ports of the circuit within the enclosure to connect the circuit to other integrated circuits and/or to a printed circuit board. A portion of the lead terminals outside of the enclosure has a specially shaped flared region that establishes the characteristic impedance of the circuit on the lead lines outside of the enclosure.

Claims

1. A microstrip lead line electrically connected to an electronic circuit, said circuit having a characteristic impedance and being positioned within an enclosure, said lead line having a predetermined width within the enclosure, said lead line extending out of the enclosure and including a flared portion that initially flares outward adjacent to an exterior wall of the enclosure where the flared portion has a width greater than the width of the lead line within the enclosure, said flared portion providing that the lead line outside of the enclosure is substantially impedance matched to the lead line within the enclosure.

2. The lead line according to claim 1 wherein the circuit is a microelectronic circuit operating in the microwave frequency range having a characteristic impedance of about 50 ohms, wherein the flared portion also has a characteristic impedance of about 50 ohms.

3. The lead line according to claim 1 wherein the flared portion includes outwardly extending flared edges that extend outward in a symmetrical manner adjacent to the exterior wall of the enclosure, inwardly extending flared edges that extend inward in a symmetrical manner that narrows the width of the flared portion and rounded edge areas between the outwardly extending flared edges and the inwardly extending flared edges.

4. The lead line according to claim 1 wherein the flared portion extends from a rectangular shaped portion of the lead line within the enclosure and returns to a rectangularly shaped portion of the lead line outside of the enclosure, wherein the rectangularly shaped portion of the lead line outside of the enclosure is wider than the rectangularly shaped portion of the lead line within the enclosure.

5. The lead line according to claim 1 wherein the lead line includes curved sections within the exterior wall of the enclosure that flare into the flared portion.

6. The lead line according to claim 1 wherein the flared portion is electrically connected to a signal line outside of the enclosure.

7. The lead line according to claim 6 wherein the signal line is a microstrip signal line on a printed circuit board.

8. An enclosure assembly comprising:

an enclosure, said enclosure including a metal base layer, a bottom layer, a side wall portion and a cover, said bottom layer including an opening that exposes the base layer;

at least one microelectronic circuit, said microelectronic circuit being positioned within the opening on the base layer, said microelectronic circuit including at least one electrical port; and

at least one microstrip lead line, said at least one microstrip lead line being electrically connected to the at least one electrical port and extending through the enclosure, said lead line including a flared region outside of the enclosure adjacent to an outside surface of the side wall portion, said flared region initially flaring outward from the outside surface of the side wall portion, said flared region providing that the lead line outside of the enclosure is substantially impedance matched to a characteristic impedance of the at least one circuit.

9. The enclosure assembly according to claim 8 wherein the at least one microelectronic circuit operates in the microwave frequency range and has a characteristic impedance of about 50 ohms.

10. The enclosure assembly according to claim 8 wherein the bottom layer, the side wall portion and the cover are made of a Teflon material.

11. The enclosure assembly according to claim 8 wherein the bottom layer, the side wall portion and the cover are made of a plastic material.

12. The enclosure assembly according to claim 8 wherein the flared portion includes outwardly extending flared edges that extend outward in a symmetrical manner adjacent to the outside surface of the side wall portion, inwardly extending flared edges that extend inwardly in a symmetrical manner that narrows the width of the flared portion and rounded edge areas between the outwardly extended flared edges and the inwardly extended flared edges.

13. The enclosure assembly according to claim 12 wherein the enclosure is mounted on a printed circuit board, and wherein the inwardly extending flared edges extend downward to contact a signal trace on the printed circuit board.

14. The enclosure assembly according to claim 8 wherein the flared portion extends from a rectangularly shaped portion of the lead within the enclosure and returns to a rectangularly shaped portion of the lead line outside of the enclosure, wherein the rectangular shape portion of the lead line outside of the enclosure is wider than the rectangularly shaped portion of the lead line within the enclosure.

15. The enclosure assembly according to claim 8 wherein the lead line includes curved sections within the side wall portion that flare into the flared portion.

16. The enclosure assembly according to claim 8 wherein the enclosure is mounted on a printed circuit board and the at least one lead line is electrically connected to a signal trace on the printed circuit board.

17. A lead line electrically connected to an electronic circuit, said electronic circuit having a characteristic impedance and being positioned within an enclosure, said lead line comprising:

an inside portion being positioned within the enclosure and being electrically connected to the circuit, said inside portion having a rectangular shape; and

an outside portion being positioned outside the enclosure and being electrically connected to the inside portion, said outside portion including a flared portion, said flared portion including outwardly extending flared edges that extend outward in a symmetrical manner adjacent to the enclosure, inwardly extending flared edges that extend inward in a symmetrical manner that narrows the width of the flared portion and rounded edge areas between the outwardly extending flared edges and the inwardly extending flared edges, wherein the flared portion causes the outside portion to be impedance matched to the inside portion.

18. The lead line according to claim 17 wherein the outside portion includes a rectangular shaped portion adjacent to the flared portion, wherein a width of the rectangular portion of the outside portion is greater than a width of the inside portion.

19. The lead line according to claim 17 wherein the inside portion includes a curved section within an exterior wall of the enclosure, wherein the curved section curves into the outwardly extending flared edges of the flared portion.

20. The lead line according to claim 17 wherein the flared portion is electrically connected to a signal line outside of the enclosure.