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Dive into the research topics where Chien-Feng Lee is active.

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Featured researches published by Chien-Feng Lee.


IEEE Microwave and Wireless Components Letters | 2008

A Divide-by-3 Injection Locked Frequency Divider With Single-Ended Input

Sheng-Lyang Jang; Chien-Feng Lee; Wei-Hsung Yen

This letter proposes a new divide-by-3 CMOS injection locked frequency divider (ILFDMOS. ) fabricated in a 0.18-mum CMOS process and describes the operation principle of the ILFD. The ILFD circuit is realized with a double cross-coupled CMOS LC-tank oscillator with an injection MOS. The self-oscillating voltage controlled oscillator is injection-locked by third-harmonic input to obtain the division order of three. Measurement results show that at the supply voltage of 1.8 V, the free-running frequency is from 1.62 to 1.89 GHz. At the incident power of 5 dBm, the locking range is from the incident frequency 4.85 to 5.7 GHz.


IEEE Microwave and Wireless Components Letters | 2008

A Low Voltage 0.35

Sheng-Lyang Jang; Chih-Yeh Lin; Chien-Feng Lee

This letter proposes a new CMOS injection locked frequency divider (ILFD) fabricated in a 0.35 mum CMOS process. The ILFD circuit is realized with a cross-coupled CMOS LC-tank oscillator, and the injecticon is carried out through the bodies of cross- coupled transistors. The self-oscillating ILFD is injection-locked by second-(third-) harmonic input to obtain the division order of two (three). Measurement results show that at the supply voltage of 1.5 V and at the incident power of 10 dBm, the locking range is from the incident frequency 6.94 to 8.41 GHz in the divide-by-3 mode and the operation range is from the incident frequency 4.56 to 5.59 GHz in the divide-by-2 mode.


IEEE Microwave and Wireless Components Letters | 2009

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Sheng-Lyang Jang; Jhong-Chen Luo; Chia-Wei Chang; Chien-Feng Lee; Jhin-Fang Huang

A new injection-locked frequency divider (ILFD) using a standard 0.18 mum CMOS process is presented. The ILFD is based on a differential Colpitts voltage controlled oscillator (VCO) with a direct injection MOSFET for coupling an external signal to the resonators. The VCO is composed of two single-ended VCOs coupled with two transformers. Measurement results show that at the supply voltage of 1.4 V the dividers free-running frequency is tunable from 4.77 to 5.08 GHz, and the proposed circuit can function as a first harmonic injection-locked oscillator, divide-by-2, -3, and -4 frequency divider. At the incident power of 0 dBm the divide-by-2 operation range is from the incident frequency 7.7 to 11.5 GHz and the divide-by-4 operation range is from the incident frequency 18.9 to 20.2 GHz.


IEEE Microwave and Wireless Components Letters | 2008

m CMOS FrequencyDivider With the Body Injection Technique

Sheng-Lyang Jang; Stewart Huang; Chien-Feng Lee; Miin-Horng Juang

This letter presents a new quadrature voltage-controlled oscillator (QVCO). The LC-tank QVCO consists of two first-harmonic injection-locked oscillators (ILOs). The outputs of one ILO are injected to the gates of the tail transistors on the other ILO and vice versa so as to force the two ILOs operate in quadrature. The proposed CMOS QVCO has been implemented with the TSMC 0.18 mum CMOS technology and the die area is 0.582 times 0.972 mm2. At the supply voltage of 1.0 V, the total power consumption is 8.0 mW. The free-running frequency of the QVCO is tunable from 5.31 GHz to 5.75 GHz as the tuning voltage is varied from 0.0 V to 1.0 V. The measured phase noise at 1 MHz offset is -120.01 dBc/Hz at the oscillation frequency of 5.31 GHz and the figure of merit (FOM) of the proposed QVCO is about -185.48 dBc/Hz.


IEEE Microwave and Wireless Components Letters | 2007

LC -Tank Colpitts Injection-Locked Frequency Divider With Even and Odd Modulo

Sheng-Lyang Jang; Chien-Feng Lee

This letter proposes a wideband injection-locked frequency divider (ILFD) and describes the operation principle of the ILFD. The circuit is made of a differential CMOS LC-tank oscillator and is based on the direct injection topology. The wideband function is obtained by tuning the switch across the tank inductors. The divide-by-two ILFD can provide wide locking range and the measurement results show that at the supply voltage of 1.8 V, the dual-band divider free-running frequencies are from 1.77 to 2.17 GHz for the low-band mode, and from 2.59 to 3.2 GHz for the high-band mode. At the incident power of 0 dBm, the locking range is about 1.7 GHz from the incident frequency 3.31 to 5.01 GHz at low band and 4.06 GHz from 3.94 to 8.0 GHz at high-band mode. The circuit can be used as a single wideband ILFD.


IEICE Transactions on Electronics | 2008

CMOS Quadrature VCO Implemented With Two First-Harmonic Injection-Locked Oscillators

Sheng-Lyang Jang; Chia-Wei Chang; Chien-Feng Lee; Jhin-Fang Huang

This paper proposes a wide-locking range divide-by-3 frequency divider employing 3D helical inductors fabricated in the 0.18-μm 1P6M CMOS technology. The divider consists of an nMOS cross-coupled LC oscillator and two injection MOSFETs in series with the cross-coupled NMOSFETs, and the LC resonator is composed of two 3D helical inductors and varactors. The aim of using 3D inductor is to reduce chip size. At the supply voltage of 1.2V, the divider free-running frequency is tunable from 2.1GHz to 2.6GHz, and at the incident power of 0dBm the locking range is about 2.11GHz (29.16%), from the incident frequency 5.99GHz to 8.1GHz. The core power consumption is 4.56mW. The die area is 0.664×0.831mm2.


IEEE Microwave and Wireless Components Letters | 2007

A Wide Locking Range

Chien-Feng Lee; Sheng-Lyang Jang; Miin-Horng Juang

This letter proposes a new wideband Colpitts injection locked frequency divider (ILFD) and describes the operation principle of the ILFD. The circuit consists of a differential CMOS LC-tank oscillator and a direct injection topology. The divide-by-two ILFD can provide wide locking range, and the measurement results show that at the supply voltage of 2.4 V, the tuning range of the free running ILFD is from 4.46 to 5.6 GHz, about 1.14 GHz, and the locking range of the ILFD is from 8.03 to 11.63 GHz, about 3.6 GHz, at the injection signal power of 0 dBm. The ILFD dissipates 19.92 mW at a supply voltage of 2.4 V and was fabricated in 1P6M 0.18 mum CMOS process. At the tuning voltage of 1.2 V, the measured phase noise of the free running ILFD is -110.8 dBc/Hz at 1 MHz offset frequency from 4.94 GHz and the phase noise of the locked ILFD is -135.4 dBc/Hz, while the input signal power is -4 dBm.


IEICE Transactions on Electronics | 2008

LC

Sheng-Lyang Jang; Chia-Wei Chang; Sheng-Chien Wu; Chien-Feng Lee; Lin-yen Tsai; Jhin-Fang Huang

Novel low phase noise quadrature voltage-controlled oscillator (QVCO) and quadrature injection locked frequency divider (QILFD) with two coupled Hartley VCOs are proposed and implemented using the standard TSMC 0.18μm CMOS 1P6M process. The QVCO employs pMOS as the core to reduce the up-conversion of low-frequency device noise to RF phase noise. It uses super-harmonic coupling technique to couple two differential Hartley VCOs and four small-size coupling transistors to set the directivity of quadrature output phases. At the 1.7V supply voltage, the output phase noise of the QVCO is -124dBc/Hz at 1MHz offset frequency from the carrier frequency of 4.12GHz, and the figure of merit is -185dBc/Hz. At the supply voltage of 1.7V, the total power consumption is 13.1mW. At the supply voltage of 1.5V, the tuning range of the free-running QILFD is from 2.05GHz to 2.36GHz, about 310MHz, and the locking range of the ILFD is from 3.99 to 5.19GHz, about 1.20GHz, at the injection signal power of 0dBm.


IEEE Microwave and Wireless Components Letters | 2008

-Tank Injection-Locked Frequency Divider

Sheng-Lyang Jang; Ming-Hsiang Suchen; Chien-Feng Lee

This letter proposes a wide locking range and low power complementary Colpitts injection-locked frequency divider (ILFD) employing a 3-D helical transformer. The proposed ILFD consists of two single-ended complementary Colpitts oscillators coupled by a 3-D transformer to form a differential oscillator. The aim of using the 3-D transformer is to reduce chip size. The divide-by-2 LC-tank ILFD is implemented by adding an injection nMOS between the differential outputs of the voltage controlled oscillator. The measurement results show that at the supply voltage of 1.8 V, the divider free-running frequency is tunable from 4.24 to 4.8 GHz. At the incident power of 0 dBm, vtune=0.9 V, and V DD=1.5 V, the locking range is about 2.4 GHz (26.9%), from the incident frequency 7.7 to 10.1 GHz. The core power consumption is 3.9 mW. The die area is 0.548times 0.656 mm2.


international symposium on vlsi design, automation and test | 2008

Divide-by-3 LC Injection Locked Frequency Divider Implemented with 3D Inductors

Sheng-Lyang Jang; Chun‐Yuan Chiu; Chien-Feng Lee

This paper presents a novel differential voltage controlled oscillator (VCO). The VCO uses a closed-loop ring inductor and is composed of two single-ended complementary Colpitts LC VCOs coupled by two identical inductors and is implemented in a standard 0.18 mum CMOS technology. This differential VCO operates at 5.76-6.76 GHz. The measured phase noise of the VCO operating at 6.7 GHz is -118.5 dBc/Hz at 1-MHz offset while the VCO draws 3.75 mA and 5.625 mW consumption from a supply voltage of 1.5 V.

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Sheng-Lyang Jang

National Taiwan University of Science and Technology

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Miin-Horng Juang

National Taiwan University of Science and Technology

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Chia-Wei Chang

National Taiwan University of Science and Technology

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Jhin-Fang Huang

National Taiwan University of Science and Technology

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Jui-Cheng Han

National Taiwan University of Science and Technology

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Chun‐Yuan Chiu

National Taiwan University of Science and Technology

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Hwan-Mei Chen

Lunghwa University of Science and Technology

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Jhong-Chen Luo

National Taiwan University of Science and Technology

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Lin-yen Tsai

National Taiwan University of Science and Technology

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Sheng‐Chien Wu

National Taiwan University of Science and Technology

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