Christopher M Murphy

US Patent:

20200264217, Aug 20, 2020

Filed:

Feb 14, 2019

Appl. No.:

16/276494

Inventors:

- San Diego CA, US
Chih-Chieh Cheng - Poway CA, US
Christopher C. Murphy - Lake Zurich IL, US
Tero Tapio Ranta - San Diego CA, US

International Classification:

G01R 19/25
H03F 1/02
H04B 10/079

Abstract:

A power detector with wide dynamic range. The power detector includes a linear detector, followed by a voltage-to-current-to-voltage converter, which is then followed by an amplification stage. The current-to-voltage conversion in the converter is performed logarithmically. The power detector generates a desired linear-in-dB response at the output. In this power detector, the distribution of gain along the signal path is optimized in order to preserve linearity, and to minimize the impact of offset voltage inherently present in electronic blocks, which would corrupt the output voltage. Further, the topologies in the sub-blocks are designed to provide wide dynamic range, and to mitigate error sources. Moreover, the temperature sensitivity is designed out by either minimizing temperature variation of an individual block such as the v-i-v detector, or using two sub-blocks in tandem to provide overall temperature compensation. In one aspect, active resistors are used in order to compensate for temperature variations.

US Patent:

20180262163, Sep 13, 2018

Filed:

Feb 28, 2018

Appl. No.:

15/908354

Inventors:

- San Diego CA, US
Tero Tapio Ranta - San Diego CA, US
Christopher C. Murphy - Lake Zurich IL, US
Robert Mark Englekirk - Littleton CO, US

International Classification:

H03F 1/30
H03F 3/19
H03F 3/21

Abstract:

Temperature compensation circuits and methods for adjusting one or more circuit parameters of a power amplifier (PA) to maintain approximately constant Gain versus time during pulsed operation sufficient to substantially offset self-heating of the PA. Some embodiments compensate for PA Gain “droop” due to self-heating using a Sample and Hold (S&H) circuit. Other embodiments include bias compensation circuits that directly regulate a bias signal to an amplifier stage as a function of localized heating of one or more of amplifier stages. Such bias compensation circuits include physical placement of at least one bias compensation circuit element in closer proximity to at least one amplifier stage than other bias compensation circuit elements. One bias compensation circuit embodiment includes a temperature-sensitive current mirror circuit for regulating the bias signal. Another bias compensation circuit embodiment includes a temperature-sensitive element having a positive temperature coefficient (PTC) for regulating the bias signal.

US Patent:

20180262166, Sep 13, 2018

Filed:

Feb 28, 2018

Appl. No.:

15/908469

Inventors:

- San Diego CA, US
Tero Tapio Ranta - San Diego CA, US
Christopher C. Murphy - Lake Zurich IL, US
Robert Mark Englekirk - Littleton CO, US

International Classification:

H03F 1/30
H03F 3/213
H03G 3/30
H03F 3/195
H03F 3/68

Abstract:

Temperature compensation circuits and methods for adjusting one or more circuit parameters of a power amplifier (PA) to maintain approximately constant Gain versus time during pulsed operation sufficient to substantially offset self-heating of the PA. Some embodiments compensate for PA Gain “droop” due to self-heating using a Sample and Hold (S&H) circuit. Other embodiments include bias compensation circuits that directly regulate a bias signal to an amplifier stage as a function of localized heating of one or more of amplifier stages. Such bias compensation circuits include physical placement of at least one bias compensation circuit element in closer proximity to at least one amplifier stage than other bias compensation circuit elements. One bias compensation circuit embodiment includes a temperature-sensitive current mirror circuit for regulating the bias signal. Another bias compensation circuit embodiment includes a temperature-sensitive element having a positive temperature coefficient (PTC) for regulating the bias signal.

US Patent:

20160029877, Feb 4, 2016

Filed:

Oct 15, 2015

Appl. No.:

14/883833

Inventors:

CHRISTOPHER MURPHY - ORLANDO FL, US

International Classification:

A61B 1/00
A61M 25/01

Abstract:

A medical scope attachment device and system includes one or more expandable rings, each having a resilient main body and an inside diameter defining a central opening that corresponds to a dimension of a medical scope. One or more sets of opposing magnetic elements are disposed within each of the rings. The system also includes a ring attachment device having a shelf that is interposed between a pair of opposing electromagnets. The ring attachment device functioning to transition the expandable rings between an expanded and non-expanded state to receive an existing medical scope.

US Patent:

20150148593, May 28, 2015

Filed:

Nov 22, 2013

Appl. No.:

14/087475

Inventors:

CHRISTOPHER MURPHY - ORLANDO FL, US

International Classification:

A61B 1/00

US Classification:

600102

Abstract:

A medical scope attachment device and system includes one or more expandable rings, each having a resilient main body and an inside diameter defining a central opening that corresponds to a dimension of a medical scope. One or more sets of opposing magnetic elements are disposed within each of the rings. The system also includes a ring attachment device having a shelf that is interposed between a pair of opposing electromagnets. The ring attachment device functioning to transition the expandable rings between an expanded and non-expanded state to receive an existing medical scope.