Hanil Lee

US Patent:

8310312, Nov 13, 2012

Filed:

Aug 11, 2009

Appl. No.:

12/539507

Inventors:

Hanil Lee - San Diego CA, US
Li-Chung Chang - Irvine CA, US

Assignee:

QUALCOMM, Incorporated - San Diego CA

International Classification:

H03F 3/68

US Classification:

330295

Abstract:

Amplifiers with improved linearity and noise performance are described. In an exemplary design, an apparatus includes first through sixth transistors. The first transistor receives an input signal and provides an amplified signal. The second transistor receives the amplified signal and provides signal drive for an output signal. The third transistor receives the input signal and provides an intermediate signal. The fourth transistor provides bias for the third transistor in a high linearity mode. The fifth transistor receives the intermediate signal and provides signal drive for the output signal in a low linearity mode. The third and fourth transistors form a deboost path that is enabled in the high linearity mode to improve linearity. The third and fifth transistors form a cascode path that is enabled in the low linearity mode to improve gain and noise performance. The sixth transistor generates distortion component used to cancel distortion component from the first transistor.

US Patent:

8270499, Sep 18, 2012

Filed:

May 15, 2009

Appl. No.:

12/467111

Inventors:

Li-Chung Chang - Irvine CA, US
Maulin P. Bhagat - San Diego CA, US
Hanil Lee - San Diego CA, US
Ravi Sridhara - San Diego CA, US

Assignee:

QUALCOMM, Incorporated - San Diego CA

International Classification:

H04B 3/00
H04L 27/00

US Classification:

375258, 375316

Abstract:

A receiver with a balanced I/Q transformer is described. In an exemplary design, the receiver includes an LNA that amplifies a received RF signal and provides a single-ended RF signal to the balanced I/Q transformer. The balanced I/Q transformer includes at least one primary coil and first and second secondary coils. The first secondary coil is magnetically coupled to the at least one primary coil and provides a first differential RF signal to a first mixer. The second secondary coil is magnetically coupled to the at least one primary coil and provides a second differential RF signal to a second mixer. The first and second mixers downconvert the first and second differential RF signals with I and Q LO signals, respectively, and provide differential I and Q downconverted signals. The primary and secondary coils may be fabricated on two conductive layers of an integrated circuit.

US Patent:

20210297046, Sep 23, 2021

Filed:

Mar 23, 2020

Appl. No.:

16/827280

Inventors:

- San Diego CA, US
Ramkumar SIVAKUMAR - San Diego CA, US
Qubo ZHOU - San Diego CA, US
Xinwang ZHANG - San Diego CA, US
Hanil LEE - San Diego CA, US
Dongyang TANG - San Diego CA, US
Vijayakumar DHANASEKARAN - San Diego CA, US

International Classification:

H03F 1/02
H03F 3/21

Abstract:

A power amplifier provides reduction of click and pop in audio applications. The power amplifier includes a first amplifier and an auxiliary amplifier. The auxiliary amplifier is used to ramp the power amplifier output from ground to an offset voltage to reduce the “click and pop” sound. The first amplifier and the auxiliary amplifier having a shared feedback loop. An output of the first amplifier and an output of the auxiliary amplifier may be switchably coupled to the shared feedback loop. A wave generator controls a switch to couple the first amplifier output or the auxiliary amplifier output to the shared feedback loop.