Microstrip line of different widths, ground planes of different distances

Patent metadata

Field	Value
Publication number	US-9405064-B2
Application number	US-201213439557-A
Country	US
Kind code	B2
Filing date	Apr 4, 2012
Priority date	Apr 4, 2012
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

An apparatus is provided. There is a circuit assembly with a package substrate and an integrated circuit (IC). The package substrate has a microstrip line, and the IC is secured to the package substrate and is electrically coupled to the microstrip line. A circuit board is also secured to the package substrate. A dielectric waveguide is secured to the circuit board. The dielectric waveguide has a dielectric core that extends into a transition region located between the dielectric waveguide and the microstrip line, and the microstrip line is configured to form a communication link with the dielectric waveguide.

First claim

The invention claimed is:

1. An assembly comprising:
(A) a microstrip line of conductive material, the microstrip line having a first portion with a first width and a second portion with a second width greater than the first width;
(B) an integrated circuit electrically coupled to the first portion of the microstrip line;
(C) a first ground plane of conductive material under the integrated circuit and extending out from under the integrated circuit and under the first portion of the microstrip line and not under the second portion of the microstrip line at a first distance under the microstrip line;
(D) a second ground plane of conductive material electrically coupled to the first ground plane and extending under and beyond the second portion of the microstrip line at a second distance under the microstrip line greater than the first distance;
(E) a base substrate having a top surface; and
(F) a dielectric waveguide having a dielectric core and dielectric cladding around the core, the core having one surface formed on the top surface of the substrate, and a first end portion of the dielectric core being coupled to the second portion of the microstrip line over the second ground plane.

2. The assembly of claim 1 including a package substrate carrying the integrated circuit and the microstrip line.

3. The assembly of claim 1 including a solder ball coupling the first ground plane to the second ground plane.

4. The assembly of claim 1 in which the dielectric core has a first dielectric constant, the base substrate has a second dielectric constant lower than the first dielectric constant, and the dielectric cladding has a third dielectric constant lower than the first dielectric constant.

5. The assembly of claim 1 in which the dielectric core has a first dielectric constant, the base substrate has a second dielectric constant lower than the first dielectric constant, and the dielectric cladding has a third dielectric constant similar to the second dielectric constant.

6. The assembly of claim 1 in which the microstrip line has a third portion joining the first portion and second portion, the third portion widening from the first portion to the second portion.

7. The assembly of claim 1 in which the microstrip line has a third portion joining the first portion and second portion, the third portion widening from the first portion to the second portion and is rounded.

8. The assembly of claim 1 in which the dielectric core is generally rectangular in cross section and has one, flat side attached to the base substrate and cladding on the other three sides.

9. The assembly of claim 1 in which the first and second distances present about 50 ohms of matching impedance to the respective first and second portions of the microstrip line.

10. The assembly of claim 1 in which the base substrate is a printed circuit board.

11. The assembly of claim 1 in which the second ground plane extends under the integrated circuit, the first ground plane, and the dielectric waveguide.

12. The assembly of claim 1 in which the dielectric waveguide has another end portion, and including another microstrip line coupled to the another end of the dielectric waveguide, and another integrated circuit coupled to the another microstrip line.

Assignees

• Herbsommer Juan A
• Payne Robert F
• Corsi Marco
• Haroun Baher S
• Ali Hassan
• Texas Instruments Inc

Inventors

• Herbsommer Juan A
• Payne Robert F
• Corsi Marco
• Haroun Baher S
• Ali Hassan

Classifications

• H05K1/18

  structurally associated with non-printed electric components (H05K1/16 takes precedence) · CPC title

• H05K1/115

  Via connections; Lands around holes or via connections (H05K1/112 takes precedence) · CPC title

• H01P3/16

  Dielectric waveguides, i.e. without a longitudinal conductor · CPC title

• G02B6/12004 Primary

  Combinations of two or more optical elements · CPC title

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title