Andrew C Chen

US Patent:

7642946, Jan 5, 2010

Filed:

Apr 7, 2008

Appl. No.:

12/098842

Inventors:

Marcel L. Lugthart - Aliso Viejo CA, US
Andrew R. Chen - Redondo Beach CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03M 1/34

US Classification:

341163, 341154, 341144, 341155

Abstract:

A system and method are provided allowing for successive approximation analog to digital conversion. A first differential voltage is sampled and held during a first cycle. The first differential voltage is converted to a differential current. A second differential voltage is generated based on the differential current flowing through parallel-coupled respective first and second variable resistances. First and second portions of the second differential voltage are compared to produce a comparison result therefrom. Successive approximation is used to generate a signal based on the comparison result, the signal being an output signal and being used to control resistances of respective ones of the first and second variable resistances during subsequent cycles.

US Patent:

7944251, May 17, 2011

Filed:

Mar 9, 2009

Appl. No.:

12/381227

Inventors:

Andrew Chen - Redondo Beach CA, US
Joseph Aziz - Irvine CA, US
Derek Tam - Irvine CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03B 1/00

US Classification:

327108, 327109, 327512

Abstract:

According to one exemplary embodiment, a transmitter module includes a line drive including a current digital-to-analog converter, where the line driver provides an analog output waveform. The current digital-to-analog converter receives a digitally filtered input waveform including at least two voltage steps. The at least two voltage steps of the digitally filtered input waveform cause a rise time of the analog output waveform to have a reduced dependency on process, voltage, and temperature variations in the line driver, while meeting stringent rise time requirements. The digitally filtered input waveform has an initial voltage level and a final voltage level, where the final voltage level is substantially equal to a sum of the at least two voltage steps of the digitally filtered input waveform.

US Patent:

7982491, Jul 19, 2011

Filed:

Apr 8, 2009

Appl. No.:

12/384793

Inventors:

Joseph Aziz - Irvine CA, US
Andrew Chen - Redondo Beach CA, US
Derek Tam - Irvine CA, US
Agnes Neves Woo - Encino CA, US
Marcel Lugthart - Aliso Viejo CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03K 17/16
H03K 19/003

US Classification:

326 30, 326 34, 326 86

Abstract:

According to one exemplary embodiment, an active termination circuit includes at least one active termination branch, where the at least one active termination branch includes at least one transistor for providing an active termination output. The at least one active termination branch further includes an amplifier driving the at least one transistor, where the amplifier has a non-inverting input coupled to the active termination output via a feedback network. The amplifier controls a current flowing through the at least one transistor so as to provide the active termination output. The active termination output can be provided at a drain of the at least one transistor, where a source of the at least one transistor is coupled to ground through a degeneration transistor and a tail current sink.

US Patent:

8183885, May 22, 2012

Filed:

Apr 8, 2009

Appl. No.:

12/384795

Inventors:

Joseph Aziz - Irvine CA, US
Andrew Chen - Redondo Beach CA, US
Derek Tam - Irvine CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03K 19/094

US Classification:

326 86, 326 83, 327109, 341145

Abstract:

In one embodiment, a circuit for providing a tail current for a line driver includes an adjustable current source. The adjustable current source includes a number of current source cells coupled together in a parallel configuration, where the current source cells are configured to provide the tail current for the line driver in response to a digital control signal. The circuit can further include a digital core coupled to the adjustable current source, where the digital core provides the digital control signal. The digital control signal provides a number of bits, where each bit controls one of the current source cells. In one embodiment, a current source cell can comprise a number of current source sub-cells. The current source cells can be configured to provide the tail current for the line driver in response to the digital control signal when the line driver is operating in a class AB mode.

US Patent:

8243510, Aug 14, 2012

Filed:

Aug 30, 2006

Appl. No.:

11/514029

Inventors:

Andrew Chen - Redondo Beach CA, US
Bibhudatta Sahoo - San Diego CA, US
Ali Anvar - Aliso Viejo CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

G11C 11/34

US Classification:

36518501, 36518514, 257315

Abstract:

According to one exemplary embodiment, a memory cell in a semiconductor chip includes a non-volatile memory transistor, a control gate, and a floating gate. The control gate is capacitively coupled to the floating gate of the non-volatile memory transistor by a metal capacitor. The metal capacitor can be formed in one or more metal levels and in one embodiment is in a shape of a comb with multiple fingers. In one embodiment, the non-volatile memory transistor is an NMOS non-volatile memory transistor.

US Patent:

8289046, Oct 16, 2012

Filed:

Jun 30, 2011

Appl. No.:

13/173706

Inventors:

Joseph Aziz - Irvine CA, US
Andrew Chen - Redondo Beach CA, US
Derek Tam - Irvine CA, US
Agnes Neves Woo - Encino CA, US
Marcel Lugthart - Aliso Viejo CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03K 17/16
H03K 19/003

US Classification:

326 30, 326 34, 326 86, 326 90

Abstract:

According to one exemplary embodiment, an active termination circuit includes at least one active termination branch, where the at least one active termination branch includes at least one transistor for providing an active termination output. The at least one active termination branch further includes an amplifier driving the at least one transistor, where the amplifier has a non-inverting input coupled to the active termination output via a feedback network. The amplifier controls a current flowing through the at least one transistor so as to provide the active termination output. The active termination output can be provided at a drain of the at least one transistor, where a source of the at least one transistor is coupled to ground through a degeneration transistor and a tail current sink.

US Patent:

8598917, Dec 3, 2013

Filed:

Apr 27, 2011

Appl. No.:

13/095688

Inventors:

Andrew Chen - Redondo Beach CA, US
Joseph Aziz - Irvine CA, US
Derek Tam - Irvine CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

H03B 1/00

US Classification:

327108, 327109

Abstract:

According to one exemplary embodiment, a transmitter module includes a line drive including a current digital-to-analog converter, where the line driver provides an analog output waveform. The current digital-to-analog converter receives a digitally filtered input waveform including at least two voltage steps. The at least two voltage steps of the digitally filtered input waveform cause a rise time of the analog output waveform to have a reduced dependency on process, voltage, and temperature variations in the line driver, while meeting stringent rise time requirements. The digitally filtered input waveform has an initial voltage level and a final voltage level, where the final voltage level is substantially equal to a sum of the at least two voltage steps of the digitally filtered input waveform.

US Patent:

51126877, May 12, 1992

Filed:

Sep 30, 1991

Appl. No.:

7/767768

Inventors:

Richard L. Frentzel - Chino Hills CA
Andrew Chen - Covina CA

Assignee:

Advanced Products Inc. - Cheshire CT

International Classification:

B32B 516

US Classification:

428402

Abstract:

A thermally curable conductive polymer thick film composition comprising, by weight: (a) about 3-15 parts of at least one thermoplastic vinyl acetate/vinyl chloride/dicarboxylic acid multipolymer resin; (b) a second thermoplastic resin selected from the group consisting of: (i) about 1-6 parts of at least one thermoplastic polyurethane resin; (ii) about 2-10 parts of at least one thermoplastic polyurethane resin; (iii) about 1-10 parts of a mixture of at least one thermoplastic polyurethane and at least one thermoplastic polyester resin; (c) about 0. 05-1 parts of a tertiary amine; (d) an effective amount of at least one organic solvent capable of substantially dissolving (a), (b), and (c) ingredients; and (e) about 50-80 parts of silver flake.