Electronics and Telecommunications Research Institute

Chang Seok Lee

Jae Jin Lee

Kwang Eui Pyun

Min Gun Kim

Young Kwan Kim

Eun Sil Choi

Seung Yup Paek

Seung Wan Kang

Hyun Woo Joo

Sang Yun Park

Sang Dae Lee

Byung Gyu Kim

Sung Wook Kim

Kwang Jun Yun

Min Kun Kim

Choong Hwan Kim

Ingab Hwang

The present invention relates to a bias stabilization circuit, specifically to a bias stabilization circuit for minimizing the current variations of amplification transistors caused by variations of device parameters which occur during the manufacturing of high-frequency integrated circuits using field-effect transistors, and caused by variations of supply voltage and temperature. In the present invention, the above problem is solved by configuring a level shifter circuit between the drain node and the gate node of the reference voltage generation transistor. Further, by using a constant current source utilizing a depletion transistor and series feedback resistors as a reference current, this circuit becomes stable against the variations of the device parameters as well as the variations of the temperature and supply voltage.

Bias stabilization circuit

The present invention relates to a gain control circuit for a low-noise amplifier. A gain control circuit of a 2-stage low-noise amplifier comprising an input stage noise matching circuit, an intermediate impedance matching circuit, a gain control circuit, and an output stage impedance matching circuit, said gain control circuit including: a feedback circuit connected to a transistor of second stage of the 2-stage low-noise amplifier, said feedback circuit detecting the amplified signal through the first stage and the second stage, and feeding the signal back through a switch circuit; and an attenuation circuit for compensating the harmonics of the input signal.

Gain control circuit for low-noise amplifier

The present invention relates to a gain controlled amplifier, and more particularly, to a gain controlled amplifier using active feedback and variable resistance. It is an object of the present invention to provide a gain controlled amplifier minimizing the gain and the degradation of power characteristics generated when adjusting gain in a variable gain amplifier which receives signals having different power levels, amplifies them in accordance with each power level and outputs output signals in a constant power level. In order to achieve the above object, a gain controlled amplifier in accordance with the present invention comprises an amplifier and an active feedback means for negative feedbacking the output of the amplifier to the input of the amplifier, and further has a feedback amount controller inputting the controlled feedback signal to the amplifier by controlling the feedback amount of said active feedback means.

Gain controlled amplifier

The present invention relates to an equivalent circuit of a package ground terminal paddle which is used to mount a microwave integrated circuit, and more particularly, to an approximate equivalent circuit of the package ground terminal paddle by which the expressions of parasitic components can be easily expanded according to the number of gold wires that are down-bonded to the paddle, by introducing an equivalent circuit structure which takes the impedance component output from each terminal as one common impedance component and grounds the common impedance.

Equivalent circuit of package ground terminal paddle

A method for correcting a high frequency measurement error which can exactly correct the high frequency measurement error even with the use of a standard devices of which characteristic have not been verified by calculating the characteristic impedance of the correction device from the characteristics of an auxiliary measuring device calculated by using a general error correction method, and calculating again the once calculated characteristics of the auxiliary measuring device. The method in accordance with the present invention comprises the steps of modelling an auxiliary measuring device used for measuring a high frequency charateristics of the device under test by two transmission lines connected in series between two terminals and a parasitic component connected in parallel between a junction of the two transmission lines and a ground; and moving a reference measurement point to the junction of the two transmission lines by using a phase angle of each transmission line and calculating a reference impedance at the terminal of the auxiliary measuring device to which an object to be measured is connected by using the difference of the resultant reflection coefficients of each port.

Method for correcting a high frequency measurement error

Growing community of inventors

Daejon-Shi, South Korea

Chang Seok Lee