Freescale Semiconductor,inc.

Skyworks Solutions, Inc.

Li-hung Kang

Howard W Patterson

Younkyu Chung

Chong W Choi

Zhongian Yuan

A power amplifier bias circuit having a controllable current profile includes a first transistor device configured as a switch, and configured to receive a non-regulated system voltage, and a plurality of resistors configured to provide a current and configured to determine an amount of a bias current that flows through a second transistor device, where the second transistor device is part of a current mirror comprising a third transistor device and the amount of bias current flowing through the second transistor device determines a power output of the third transistor device.

Power amplifier bias circuit having controllable current profile

A disclosed self regulating biasing circuit (SRBC) includes an unregulated node that couples to an unregulated power supply that produces a supply voltage. An impedance element of the SRBC carries an unregulated current having a nominal component and a variance component between an unregulated node and a regulated node. A detection circuit connected between the unregulated node and a third node detects a variance component of a supply voltage and generates a detection current based on the variance component. A compensation circuit connected to the third node draws a compensation current, based on the detection current, from the regulated node. The SRBC is designed wherein the compensation current is approximately equal to the variance component of the unregulated current. The regulated node may be connected to a control terminal of a transistor to be biased.

Self regulating biasing circuit

An RF amplifier is disclosed having a first and second current mirror module. The first and second current mirror modules each provide current to affect the quiescent bias current of the RF amplifier.

Growing community of inventors

Gilbert, AZ, United States of America

Li-hung Kang