DAVID S. SOBEL, MD
Medical Practice at Franklin St, Oakland, CA
License number
California G39862
Category
Medical Practice
Type
Public Health & General Preventive Medicine
Address
Address
1950 Franklin St, Oakland, CA 94612
Phone
(510) 987-1000
(510) 625-6262
(510) 625-6262
Professional information
Dr. David S Sobel, Oakland CA - MD (Doctor of Medicine)
Specialties:
Family Medicine, Preventive Medicine
Address:
1950 Franklin St, Oakland 94612
(510) 987-1000 (Phone)
(510) 987-1000 (Phone)
Languages:
English
Education:
Medical School
University of California At San Francisco
Graduated: 1978
University of California At San Francisco
Graduated: 1978
Low-Noise Transmitter System And Method
US Patent:
7274915, Sep 25, 2007
Filed:
Aug 27, 2004
Appl. No.:
10/927311
Inventors:
David Sobel - Oakland CA, US
Augustine Kuo - Berkeley CA, US
Augustine Kuo - Berkeley CA, US
Assignee:
Broadcom Corporation - Irvine CA
International Classification:
H04B 1/04
US Classification:
4551142, 4551271
Abstract:
A low-noise transmitter architecture and method for high linearity, high output-swing systems such as Asymmetrical Digital Subscriber Line (ADSL) systems. The transmitter uses a switched-current DAC having a current source coupled to ground, followed by a resistive transimpedance amplifier (TIA). The resistance of the current source is typically large enough so that noise from an op-amp included in the TIA is not significantly amplified at the output. The current source may be passive and may include at least one resistor connected to ground. With a passive current source, portions of a signal output by the DAC enter either the current source or the resistive transimpedance amplifier, but not both, eliminating noise in the system produced by the current source.
Low-Noise Transmitter System And Method
US Patent:
7590393, Sep 15, 2009
Filed:
Sep 24, 2007
Appl. No.:
11/860343
Inventors:
David Sobel - Oakland CA, US
Augustine Kuo - Berkeley CA, US
Augustine Kuo - Berkeley CA, US
Assignee:
Broadcom Corporation - Irvine CA
International Classification:
H04B 1/04
US Classification:
4551142, 4551271
Abstract:
A low-noise transmitter architecture and method for high linearity, high output-swing systems such as Asymmetrical Digital Subscriber Line (ADSL) systems. The transmitter uses a switched-current DAC having a current source coupled to ground, followed by a current-to-voltage converter. The resistance of the current source is typically large enough so that noise from an op-amp included in the current-to-voltage converter is not significantly amplified at the output. The current source may be passive and may include at least one resistor connected to ground. With a passive current source, portions of a signal output by the DAC enter either the current source or the current-to-voltage converter, but not both, eliminating noise in the system produced by the current source.