Abstract: A fiber to chip coupling connecting an optical fiber to an integrated circuit. A section of fiber is laid on top of the surface of the chip, where the end of the fiber has been cut at an angle to form an angled tip. The angled tip has a flat surface which reflects light down to a waveguide grating coupler disposed on the integrated circuit. Light is reflected off the reflective surface of the angled tip by total internal reflection. The waveguide grating coupler is designed to accept the slightly diverging light beam from the reflective surface of the angled tip of the fiber. Light can also propagate through the fiber to chip coupler in the opposite direction, up from the substrate through the waveguide grating and into an optical fiber after bouncing off the reflective surface of the angled tip.
Type:
Grant
Filed:
March 11, 2004
Date of Patent:
January 9, 2007
Assignee:
Luxtera, Inc.
Inventors:
Lawrence C. Gunn, III, Thierry J. Pinguet, Maxime J. Rattier, Zhen-Li Ji, Jeremy Witzens
Abstract: A control loop system is provided that employs an active DC output control circuit that more accurately calibrates the desire voltage at a load, e.g. 3.3 volts, by adjusting a trim pin on a DC/DC converter. In a first embodiment, an active DC output control circuit calibrates a DC/DC converter that is connected to a single load. In a second embodiment, an active DC output control circuit calibrates multiple DC/DC converters that are connected to multiple loads.
Type:
Grant
Filed:
November 13, 2002
Date of Patent:
February 21, 2006
Assignee:
Summit Microelectronics
Inventors:
Kenneth C. Adkins, Theodore Martin Myers, John Tabler, Anurag Kaplish, Thomas J. O'Obrien
Abstract: Optoelectronic devices of the present invention include several embodiments of an electronically active optical waveguide made of a strip loaded waveguide with a lateral, self-aligned diode fabricated in a layer of silicon. A voltage applied across the diode changes the free carrier density in a portion of the active waveguide, which can change the refractive index in that portion of the waveguide. Changing the refractive index can cause a phase shift of an optical signal propagating down the waveguide and this effect can be used to control the optical signal. Changing the free carrier density can also change the amount of optical attenuation in a section of an active waveguide. Optoelectronic devices such as: modulators, attenuators, switches, beam diverters, tunable filters and other devices can be fabricated on a standard SOI substrate (silicon on insulator), which is typically used in the fabrication of CMOS integrated circuits.
Type:
Grant
Filed:
August 27, 2003
Date of Patent:
February 14, 2006
Assignee:
Luxtera, Inc.
Inventors:
Lawrence C. Gunn, III, Bing Li, Thierry J. Pinguet, David L. R. Press, Maxime Jean Rattier
Abstract: An avalanche photodetector (APD) is made from composite semiconductor materials. The absorption region of the APD is formed in a n-type InGaAs layer. The multiplication region of the APD is formed in a p-type silicon layer. The two layers are bonded together. The p-type silicon layer may be supported on an n+ type silicon substrate. A p-n junction formed at the interface between the silicon layer and the substrate. Alternatively, the n-type InGaAs layer may be supported on an InP substrate. In this case, a p-n junction is formed by making n-doped surface regions in the p-type silicon superlayer. In either case, the p-n junction is reverse biased for avalanche multiplication of charge carriers. The maximum of the electric field distribution in the APD under reverse bias operating conditions is located at p-n junction. This maximum is at a distance equal to about the thickness of the p-type silicon layer away from the absorption region.
Abstract: Multi-sensor system for real-time embedded monitoring of object senses mixed-mode object conditions. Various sensors separately provide disparate analog signals representing different measurable attributes regarding sensed object. For example, such sensors may separately sense temperature, pressure, or other biometric value. Then, according to specified rule set or other qualifying parameters, a digital signal is generated by a processor or controller to indicate one or more condition of the sensed object according to certain sensor input values. Additionally, such multi-sensor scheme may be coupled to a digital network or otherwise coupled thereto for simulation and/or communication applications.
Type:
Grant
Filed:
December 23, 1998
Date of Patent:
July 2, 2002
Inventors:
Dennis Sunga Fernandez, Irene Hu Fernandez
Abstract: A content addressable memory (CAM) with built-in power saving management. The CAM includes a comparator circuit region that is coupled to a match line (ML) as well as a swing line (SL). The comparator circuit region is coupled to CAM cells. The comparator region is adapted for comparing match data with stored data within the CAM cells. The ML has its ML voltage level pre-charged to a pre-charge voltage level (Vc). Additionally, the SL is pre-charged to ground. In turn, in response to a data mismatch detected by the comparator, the ML voltage level drops from Vc by a ML voltage swing (Vswing) while the SL charge shares with the Ml. Advantageously, in response to this data mismatch, the SL charge shares with the ML such that Vswing is approximately less or equal to Vc/2. That is, the charge sharing prevents the ML from discharging all the way to ground.