David Brett Newman

US Patent:

6407634, Jun 18, 2002

Filed:

Jun 16, 2000

Appl. No.:

09/595073

Inventors:

Joseph Staudinger - Gilbert AZ
David A. Newman - Tempe AZ
Benjamin R. Gilsdorf - Phoenix AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03F 338

US Classification:

330149, 330 10, 375297, 455 63, 455126

Abstract:

A linear envelope tracking radio frequency (RF) power amplifier having an adaptive analog signal processing circuit. The amplifier outputs a voltage which is sampled by the adaptive analog signal processing circuit. The adaptive analog signal processing circuit generates an error signal which varies the linearity of the power amplifier. In one embodiment, the error signal controls a modulator which in turn controls the supply voltage to the power amplifier. In another embodiment, the control signal varies a controller which in turn varies a load placed on the power amplifier. The load in turn varies in linearity of the amplifier.

US Patent:

6600344, Jul 29, 2003

Filed:

Jun 26, 2000

Appl. No.:

09/605084

Inventors:

David A. Newman - Tempe AZ
Benjamin R. Gilsdorf - Phoenix AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03K 5153

US Classification:

327 58, 327 61

Abstract:

An envelope detector circuit for use in controlling a RF amplifier is provided. The envelope detector circuit includes a first semiconductor device having a first input port that receives a first input signal and a first output port that provides current to charge a capacitor in response to the first input signal. The envelope detector circuit additionally includes a first current drain coupled to the first semiconductor device and the capacitor, where the first current drain conducts current away from the capacitor. The envelope detector circuit further includes a second semiconductor device having a second input port that is set to a biasing voltage and a second output port that is coupled to the first output port of the first semiconductor device. A voltage level of the first output port is indicative of a level of an envelope of the first input signal when the voltage level remains above a threshold voltage equaling the biasing voltage minus a semiconductor voltage, and the voltage level otherwise does not fall below the threshold voltage.

US Patent:

6617920, Sep 9, 2003

Filed:

Apr 16, 2002

Appl. No.:

10/123271

Inventors:

Joseph Staudinger - Gilbert AZ
David A. Newman - Tempe AZ
Benjamin R. Gilsdorf - Phoenix AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03F 338

US Classification:

330149, 330 10, 375297, 455 63, 455126

Abstract:

A linear envelope tracking radio frequency (RF) power amplifier having an adaptive analog signal processing circuit. The amplifier outputs a voltage which is sampled by the adaptive analog signal processing circuit. The adaptive analog signal processing circuit generates an error signal which varies the linearity of the power amplifier. In one embodiment, the error signal controls a modulator which in turn controls the supply voltage to the power amplifier. In another embodiment, the control signal varies a controller which in turn varies a load placed on the power amplifier. The load in turn varies in linearity of the amplifier.

US Patent:

6750722, Jun 15, 2004

Filed:

Jun 28, 2002

Appl. No.:

10/184857

Inventors:

David A. Newman - Tempe AZ
Benjamin R. Gilsdorf - Phoenix AZ

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H03F 304

US Classification:

330296, 330307, 330285

Abstract:

A power amplifiers base current is biased by a control circuit that produces a linear relationship across varying temperatures and processes. A voltage to current converter controls a voltage follower configured operational amplifier in response to a reference device to drive the voltage and current of the power amplifier.

US Patent:

6809593, Oct 26, 2004

Filed:

Apr 28, 2003

Appl. No.:

10/424251

Inventors:

David A. Newman - Tempe AZ
Benjamin R. Gilsdorf - Phoenix AZ

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H03G 310

US Classification:

330285, 330296

Abstract:

A power amplifiers base current is biased by a control circuit that produces a linear relationship across varying temperatures and processes. A voltage to current converter controls a voltage follower configured operational amplifier in response to a reference device to drive the voltage and current of the power amplifier. A slope control circuit is coupled to the reference device to limit a maximum power control slope.

US Patent:

7276974, Oct 2, 2007

Filed:

Sep 8, 2005

Appl. No.:

11/222545

Inventors:

David A. Newman - Tempe AZ, US
Benjamin R. Gilsdorf - Phoenix AZ, US
David S. Peckham - Barrington Hills IL, US

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H02H 7/20

US Classification:

330298, 330207 P

Abstract:

Method and apparatus are provided for protecting radio frequency (RF) power amplifiers. A circuit () is provided for limiting a supply current to a first stage (Q) of the RF power amplifier having a second stage (Q) coupled to the first stage. The circuit comprises a comparator () having first and second inputs and an output, and a switching circuit () having an input coupled to the output of the comparator () and having an output configured to couple to the first stage (Q). The first input of the comparator () is configured to receive the supply current, and the second input is configured to receive a current supplied to the second stage (Q). The comparator () is configured to compare a ratio of the supply current to the first stage to the current supplied to the second stage (Q) with a predetermined value. The switching circuit () is configured to limit the supply current to the first stage (Q) when the ratio exceeds the predetermined value.

US Patent:

7301402, Nov 27, 2007

Filed:

Nov 17, 2005

Appl. No.:

11/282734

Inventors:

George B. Norris - Gilbert AZ, US
Benjamin R. Gilsdorf - Phoenix AZ, US
David A. Newman - Tempe AZ, US

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H03F 1/52

US Classification:

330298

Abstract:

A soft saturation detection circuit for a radio frequency (“RF”) power amplifier is configured to detect the onset of soft saturation in an unambiguous and accurate manner. The circuit compares the time derivative of a voltage signal indicative of the RF output power to the time derivative of a control voltage signal for the RF power amplifier. The circuit also employs a gating mechanism that ensures that a soft saturation indication signal is generated under appropriate operating conditions.

US Patent:

7440731, Oct 21, 2008

Filed:

Jul 27, 2005

Appl. No.:

11/191687

Inventors:

Joseph Staudinger - Gilbert AZ, US
Benjamin R. Gilsdorf - Phoenix AZ, US
David A. Newman - Tempe AZ, US
George B. Norris - Gilbert AZ, US
Gary W. Sadowniczak - Phoenix AZ, US
Richard E. Sherman - Mesa AZ, US

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H01Q 11/12
H04B 1/04

US Classification:

455 91, 455126, 4551271

Abstract:

A radio frequency (“RF”) power amplifier circuit as described herein is configured to detect and measure an output load mismatch and to adjust the operating characteristics of the RF power amplifier to reduce output signal distortion. The circuit includes a directional RF signal coupler that obtains a coupled reflected RF signal that is indicative of the output load mismatch. The coupled reflected RF signal is processed to generate one or more bias control signals for the RF power amplifier. In operation, a mismatch condition will result in a measurable coupled reflected RF signal and a corresponding reduction in output power from the RF power amplifier. Ultimately, the output power control mechanism strives to maintain the RF power amplifier within a linear operating range.