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Rodenbeck, Christopher T.

Publications and source records attributed to Rodenbeck, Christopher T..

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Variable bandwidth filter

A variable bandwidth filter is described herein, wherein a bandwidth of a passband of the variable bandwidth filter is dynamically tunable. The variable bandwidth tuner is implemented on a CMOS chip, and acts to filter analog signals. The variable bandwidth filter comprises a plurality of finite impulse response (FIR) filters, wherein each FIR filter comprises a plurality of tunable transconductors. The tunable transconductors are tunable in their gain.

Rodenbeck, Christopher T.↗
DOE OSTI2019

Gm-C filter and multi-phase clock circuit

Described herein is a power-efficient Gm-C filter, wherein the Gm-C filter includes several operational transconductance amplifiers (OTAs). In an example, at least two of the OTAs share a common bias current. Further, output of one of the OTAs is used to bias another one of the OTAs. Also described herein is a power-efficient clock generator circuit that is configured to output non-overlapping clock signals. The clock generator circuit includes a ring oscillator circuit, which includes several inverter stages. The clock generator circuit is well-suited for controlling operation of switches.

42 ENGINEERING↗
DOE OSTI2018

Graphene heat dissipating structure

Various technologies presented herein relate to forming one or more heat dissipating structures (e.g., heat spreaders and/or heat sinks) on a substrate, wherein the substrate forms part of an electronic component. The heat dissipating structures are formed from graphene, with advantage being taken of the high thermal conductivity of graphene. The graphene (e.g., in flake form) is attached to a diazonium molecule, and further, the diazonium molecule is utilized to attach the graphene to material forming the substrate. A surface of the substrate is treated to comprise oxide-containing regions and also oxide-free regions having underlying silicon exposed. The diazonium molecule attaches to the oxide-free regions, wherein the diazonium molecule bonds (e.g., covalently) to the exposed silicon. Attachment of the diazonium plus graphene molecule is optionally repeated to enable formation of a heat dissipating structure of a required height.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Electromagnetic isolation structure

The various technologies presented herein relate to isolating an integrated circuit from electromagnetic radiation/interference. The integrated circuit can be encapsulated in a coating (e.g., a conformal coating). A conductive layer can be formed over the coating, where the conductive layer is deposited to connect with an electromagnetic shielding layer included in a substrate upon which the integrated circuit is located thereby forming a Faraday cage around the integrated circuit. Hollow spheres can be included in the coating to improve the dielectric constant of the coating. The conductive layer can be formed from at least one of metallic material or a polymer coating which includes conductive material. The integrated circuit can be utilized in conjunction with a heat sink and further, the integrated circuit can be of a flip chip configuration.

Rodenbeck, Christopher T.↗
DOE OSTI2018

Coherent radar receiver that comprises a sigma delta modulator

Described herein are various technologies relating to processing a coherent signal. A receiver is configured to receive an analog signal, and process the analog signal to generate an input analog signal. The input analog signal has been modulated according to a suitable modulation sequence. A coherent signal sampler coherently samples the modulation sequence, and the result of such sampling is in turn used to demodulate the input analog signal. The resultant signal is then passed to a sigma delta modulator, where it is converted to digital form.

47 OTHER INSTRUMENTATION↗