US Patent No. 10,251,258

DIELECTRIC WAVEGUIDE CORE BETWEEN GROUND PLANES SECURED IN A CHANNEL


Patent No. 10,251,258
Issue Date April 02, 2019
Title Dielectric Waveguide Core Between Ground Planes Secured In A Channel
Inventorship Juan A. Herbsommer, Allen, TX (US)
Robert F. Payne, Lucas, TX (US)
Marco Corsi, Oak Point, TX (US)
Baher S. Haroun, Allen, TX (US)
Hassan Ali, Murphy, TX (US)
Assignee Texas Instruments Incorporated, Dallas, TX (US)

Claim of US Patent No. 10,251,258

1. An apparatus comprising:(a) a circuit board having a first side, a second side, an elongate channel formed in and open to the first side of the circuit board, and a first conductive ground plane that underlies at least a portion of the channel, the channel having opposed side walls that extend from the first side of the circuit board towards the second side of the circuit board, a bottom wall that extends between the side walls, and the side walls and the bottom wall are between the first and second sides of the circuit board, the circuit board having a first dielectric constant;
(b) a package substrate that is secured to the first side of the circuit board, the package substrate including a second conductive ground plane that is electrically coupled to the first ground plane, and a conductive microstrip line that is substantially parallel to the first and second ground planes, the microstrip line having:
(i) a first portion that overlays at least a portion of the second ground plane and that is separated from the second ground plane by a first distance, the first portion of the microstrip line being dimensioned to have an impedance to propagate radiation having a certain wavelength; and
(ii) a second portion that overlays at least a portion of the first ground plane and that is separated from the first ground plane by a second distance, the second distance being greater than the first distance, the second portion of the microstrip line is dimensioned to have an impedance to propagate radiation having the certain wavelength, and the second portion of the microstrip line being located within a transition region;
(c) an integrated circuit (IC) that is secured to the package substrate and that is electrically coupled to the first portion of the microstrip line; and
(d) a dielectric waveguide core that overlies at least a portion of the first ground plane, that extends under the second portion of the microstrip line in the transition region, and that is secured in and extends through the channel, the dielectric waveguide core having a second dielectric constant different from the first dielectric constant.