Samsung Electro-Mechanics Co., Ltd.

Iizuka Shinichi

Jeong Hoon Kim

Myeong Woo Han

Youn Suk Kim

Ki Joong Kim

Jun Goo Won

Kwang Du Lee

Jong Ok Ha

Young Jean Song

Nam Heung Kim

Sang Hoon Ha

Jun Kyung Na

Young Wong Jang

An apparatus that generates and limits a bias current of a power amplifier is provided. The apparatus includes a bias current circuit that generates a bias current to bias the power amplifier, and critically limit an increase in bias current, and a band gap reference circuit that provides a reference voltage or a reference current to the bias current circuit. The bias current circuit is configured to critically limit the increase in bias current, as a first bias transistor that generates the bias current is converted from a triode region to a saturation region, based on the reference voltage or the reference current.

Power amplifier with bias current generating and bias current limiting apparatus

The present invention relates to a power detection circuit and an RF signal amplification circuit having the same. According to an embodiment of the present invention, a power detection circuit including a coupling unit adjacent to an RF matching inductor to extract induced power; a rectification unit for rectifying the signal output from the coupling unit to output the rectified signal; a slope adjustment unit connected between an output terminal of the rectification unit and a ground and adjusting a voltage slope for power detection by changing the output signal of the output terminal of the rectification unit according to changes in internal impedance; and a smoothing unit for receiving the output signal of the output terminal of the rectification unit to smooth the received signal into a DC voltage for power detection using the voltage slope is provided. Further, an RF signal amplification circuit having the same is provided.

Power detection circuit and RF signal amplification circuit having the same

Disclosed herein is a power amplifier system including: a power amplifier; a power controlling unit providing driving voltage and driving current corresponding to a preset reference voltage to the power amplifier; a current controlling unit performing a control so that control current corresponding to applied control voltage flows; a bias controlling unit detecting current and voltage corresponding to the driving current of the power controlling unit and controlling bias current of the power amplifier according to the detected voltage; and a current adjusting unit detecting bias voltage corresponding to the bias current of the power amplifier and adjusting the driving current of the power controlling unit according to the detected bias voltage. Even though applied control voltage increases, current applied to the power amplifier is appropriately adjusted, thereby making it possible to improve characteristics of the power amplifier.

Power amplifier system

Growing community of inventors

Suwon-si, South Korea

Iizuka Shinichi