National Taiwan University

Academia Sinica

Taiwan University

Airwave Technologies Inc.

Huei Wang

Zuo-Min Tsai

Che-Chung Kuo

Bo-Jr Huang

Tian-Wei Huang

Shih-Fong Chao

George D Vendelin

Pei-Si Wu

Chung-Chun Chen

Jeng-Han Tsai

Yi-Ching Wu

Chao-Chieh Li

Mei-Chao Yeh

Shih-Chieh Shin

Chau-Ching Chiong

Kun-You Lin

Ming-Da Tsai

Bo-Ze Lu

Yu-Jiu Wang

Yu-Lung Tang

Chun-Lin Kuo

Yuh-Jing Hwang

Yung-Nien Jen

Che-Yu Wang

The present invention is to provide a mixing circuit, comprising: a first transistor; a second transistor; a third transistor; a first connection point connected to a gate terminal of the first transistor, a drain terminal of the second transistor and a source terminal of the third transistor; a second connection point connected to a source terminal of the first transistor and a gate terminal of the second transistor; and a third connection point connected to a drain terminal of the first transistor and a drain terminal of the third transistor.

Mixing circuit

The present invention relates to an electrostatic discharge (ESD) protection circuit, and more particularly to a band-pass structure electrostatic discharge protection circuit. An ESD protection circuit is disposed at the input of a radio frequency (RF) core circuit. The ESD protection circuit comprises a plurality of diodes and inductors constructing a plurality of discharging paths, wherein the diodes and inductors forms a band-pass filter structure. Such that, the RF core circuit with the ESD protection circuit of the present invention feature much higher ESD robustness and better RF performance than the conventional design.

Band-pass structure electrostatic discharge protection circuit

The present invention relates to an electrostatic discharge (ESD) protection circuit, and more particularly to a low parasitic capacitance electrostatic discharge protection circuit. An ESD protection circuit is established with the structure in accordance with the present invention comprising a plurality of discharging paths. The ESD protection circuit is connected to the input/output pad of a radio frequency (RF) core circuit. Such that, the RF core circuit with the ESD protection circuit of the present invention feature much higher ESD robustness. And the parasitic capacitance of the ESD protection is reduced because of the structure of the present invention.

Low parasitic capacitance electrostatic discharge protection circuit

A miniaturized dual-balanced mixer circuit based on a double spiral layout architecture is proposed, which is designed for use to provide a frequency mixing function for millimeter wave (MMW) signals, and which features a downsized circuit layout architecture that allows IC implementation to be more miniaturized than the conventional star-type dual-balanced mixer (DBM). The proposed miniaturized dual-balanced mixer circuit is distinguished from the conventional star-type DBM particularly in the use of a double spiral layout architecture for the layout of two balun circuit units. This feature allows the required layout area to be only about 15% of that of the conventional star-type DBM.

Miniaturized dual-balanced mixer circuit based on a double spiral layout architecture

A miniaturized dual-balanced mixer circuit based on a multilayer double spiral layout architecture is proposed, which is designed for use to provide a frequency mixing function for millimeter wave (MMW) signals, and which features a downsized circuit layout architecture that allows IC implementation to be more miniaturized than the conventional star-type dual-balanced mixer (DBM). The proposed miniaturized dual-balanced mixer circuit is distinguished from the conventional star-type DBM particularly in the use of a 3-dimensional double-spiral circuit layout architecture for the layout of two balun circuit units. This feature allows the required layout area to be only about 15% of that of the conventional star-type DBM.

Miniaturized dual-balanced mixer circuit based on a multilayer double spiral layout architecture

A miniaturized dual-balanced mixer circuit based on a trifilar layout architecture is proposed, which is designed for use to provide a frequency mixing function for millimeter wave (MMW) signals, and which features a downsized circuit layout architecture that allows IC implementation to be more miniaturized than the conventional star-type dual-balanced mixer (DBM). The proposed miniaturized dual-balanced mixer circuit is distinguished from the conventional star-type DBM particularly in the use of a trifilar layout architecture for the layout of two balun circuit units. This feature allows the required layout area to be only about 20% of that of the conventional star-type DBM.

Miniaturized dual-balanced mixer circuit based on a trifilar layout architecture

A switchable bandpass filter includes a first stepped-impedance resonator, a second stepped-impedance resonator wirelessly coupled to the first stepped-impedance resonator, and a first diode connected to one end of the second stepped-impedance resonator.

Switchable bandpass filter having stepped-impedance resonators loaded with diodes

The present invention relates to a low noise cascode amplifier comprising a first transistor, a second transistor, a third transistor, a first inductor, and a second inductor. Furthermore, the first transistor can connect with the second transistor via the first inductor, and the second transistor can connect with the third transistor via the second inductor; thereby, a cascode device can be formed. The inductor and the parasitic capacitances can resonate at high frequency, so that the noise figure of the cascode amplifier can be reduced.

Low noise cascode amplifier

A miniaturized multilayer hybrid-phase signal splitter circuit is proposed, which is fully equivalent in function to a conventional rat-race coupler, but with a specialized circuit layout structure that allows its IC implementation to be more miniaturized than the conventional rat-race coupler. The proposed hybrid-phase signal splitter circuit features the use of a multilayer substrate for the layout of six transmission lines in such a manner that the transmission lines in the middle layer are inductively coupled to the transmission lines on the overlying layer as well as the transmission lines on the underlying layer to form a Marchand balun. In IC implementation, the required layout area is only about 10% of the layout area for the conventional rat-race coupler.

Miniaturized multilayer hybrid-phase signal splitter circuit

A V-band radio frequency (RF) electrostatic discharge (ESD) protection circuit uses meander inductors and diodes connecting in series to provide ESD protection. When operated in low frequency, the static electricity input from a RF pad may discharge to ground or to a voltage VDD through the meander inductor and the diode, so that a core circuit is not damaged by ESD. When operated in high frequency, the high frequency stray effect of the core circuit is substantially reduced due to impedance isolation generated by the meander inductors. Therefore, a low-noised amplifier (LNA) can receive an accurate high frequency input signal.

V-band radio frequency electrostatic discharge protection circuit

A microwave or millimeter-wave balun is provided. The balun uses three edge-coupled lines along with a plurality of air bridges instead of two edge-coupled lines used in a conventional planar Marchand balun. The first edge-coupled line and the second edge-coupled line are substantially parallel, and the third edge-coupled line is disposed also substantially in parallel between the first edge-coupled line and the second edge-coupled line. The plurality of air bridges are transmission lines between the first edge-coupled line and the second edge-coupled line. The air bridges have total width longer than one half of the total length of the first edge-coupled line or the second edge-coupled line. By combining three edge-coupled-lines and a plurality of air bridges, the Marchand balun has a higher coupling coefficient and increases the operation bandwidth. The microwave monolithic integrated circuit (MMIC) mixer based on the balun can provide compact size compared to conventional ones.

Marchand balun with air bridge

A distributed active transformer (DAT) based millimeter-wave (MMW) power amplifier circuit is designed for power amplification of MMW frequency signals. The proposed MMW power amplifier circuit is characterized by distributing the input frequency signals into two sets of differential signals and by the use of a distributed active transformer circuit unit to process these two sets of differential signals to thereby generate an amplified frequency signal as the end result of output. The invention provides higher and greater added values and power added efficiency (PAE) and is ideal for use in millimeter-wave communications systems with an operation frequency around 60 GHz.

Distributed active transformer based millimeter-wave power amplifier circuit

A ring-based multi-push voltage-controlled oscillator (VCO) generates a multi-push output signal using a control voltage. The ring-based multi-push VCO includes a plurality of delay cells, a plurality of buffer amplifiers, and a bias unit. The delay cells connect each other in sequence to form a ring structure, and each delay cell connects with the respective buffer amplifier. The bias unit connects with the buffer amplifiers to output the multi-push output signal. The control voltage supplied to the delay cells is utilized to control the frequency of the multi-push output signal, and the ring structure formed by the delay cells is to multiply the frequency of the multi-push output signal to increase the frequency tuning range.

Ring-based multi-push voltage-controlled oscillator

A unilateral feedback power amplifier utilizes new feedback techniques and devices to make the amplified high-frequency signal unilateral, let the output power, power gain and impedance matching simultaneously accomplish the optimal values, and enhance the stability of the system. In this feedback amplifier, a generalized multi-port feedback circuit is in shunt with the input terminal and the output terminal of the power transistor. This generalized multi-port feedback circuit receives an amplified high-frequency signal and eliminates the reverse admittance of the amplified high-frequency signal to let the admittance value of the output amplified high-frequency signal approach zero so as to be unilateral. Moreover, the generalized multi-port feedback power amplifier differs from the conventional power amplifier of cascaded architecture in that the ground terminal of the power transistor is directly connected to the system ground. Therefore, the heat-radiating problem of the power transistor can be greatly improved.

Unilateral feedback power amplifier and method for realizing the same

A single-pole-double-throw switch is provided, which is configured to be integrated with a bandpass filtering function and includes four quarter-wavelength transmission lines connected in series, five resonators connected in parallel to each other, and four transistors connected in parallel to four of the five resonators. When two of the four transistors are turned on and the others are turned off, the single-pole-double-throw switch is equivalent to a third-order quarter-wavelength short-circuited stub bandpass filter.

Growing community of inventors

Taipei, Taiwan

Huei Wang