Jhin-Fang Huang

A Dual-Band CMOS Voltage-Controlled Oscillator Implemented With Dual-Resonance LC Tank

A new fully integrated, dual-band CMOS voltage controlled oscillator (VCO) is presented. The VCO is composed of n-core cross-coupled Colpitts VCOs and was implemented in 0.18 mum CMOS technology with 0.8 V supply voltage. The circuit allows the VCO to operate at two resonant frequencies with a common LC tank. The VCO has two control inputs, one for continuous control of the output frequency and one for band switching. This VCO is configured with 5 GHz and 12 GHz frequency bands with differential outputs. The dual-band VCO operates in 4.78-5.19 GHz and 12.19-12.61 GHz. The phase noises of the VCO operating at 5.11 and 12.2 GHz are -117.16 dBc/Hz and -112.15 dBc/Hz at 1 MHz offset, respectively, while the VCO draws 3.2/2.72 mA and 2.56/2.18 mW consumption at low/high frequency band from a 0.8 V supply.

Time-domain reflectometry using arbitrary incident waveforms

A novel time-domain reflectometry technique is developed for detecting the physical structures of transmission lines by using arbitrary waveforms. By discretizing both incident and reflected waves, we formulate the reflection coefficient of a nonuniform transmission line as a polynomial ratio in the Z-transform, wherein the numerator and denominator represent the reflected and incident waves, respectively. A reconstruction scheme is derived to obtain the characteristic impedance profile of a transmission line. Some examples are presented to illustrate the validity of this new technique.

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

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.

Chip design of a 5.6-GHz 1-V wide tuning range frequency synthesizer with Gm-boosting Colpitts VCO for biomedical application

A 5.6-GHz 1-V wide tuning range frequency synthesizer with a gain-boosting Colpitts voltage-controlled oscillator (VCO) is fabricated in TSMC 0.18 um CMOS process. In this prototype, there are two important features. First, a 1-V gain-boosting Colpitts LC VCO circuit is adopted to reduce phase noise and power consumption. Second, a class-AB current mode logic (CML) circuit is utilized in first divider stage to deal with the high frequency signal. At the supply voltages of 1-V for VCO and 1.8-V for digital circuits, measured results achieve that the VCO output frequency is tunable from 5.13~5.98 GHz corresponding to 15.4% and the locked phase noise is -105.83 dBc/Hz at 1MHz from 5.15 GHz. The power consumption is 5.6 mW and including pads, the chip area is 0.632 (0.89 × 0.71) mm2. This chip design low power consumption for biomedical application.

A Wide Locking Range Injection Locked Frequency Divider with Quadrature Outputs

This paper presents a quadrature injection locked frequency divider (ILFD) employing tunable active inductors (TAIs), which are used is to extend the locking range and to reduce die area. The CMOS ILFD is based on a new quadrature voltage-controlled oscillator (VCO) with cross-coupled switching pairs and TAI-C tanks, and was fabricated in the 0.18-μm 1P6M CMOS technology. The divide-by-2 LC-tank ILFD is performed by adding injection MOSFETs between the differential outputs of the VCO. Measurement results show that at the supply voltage of 1.8V, the divider free-running frequency is tunable from 1.34GHz to 3.07GHz, and at the incident power of 0dBm the locking range is about 6GHz (137%), from the incident frequency 1.37GHz to 7.38GHz. The core power consumption is 22.8mW. The die area is 0.63×0.55mm2.

Annealing Algorithm Applied in Optimum Design of 2.4 GHz and 5.2 GHz Dual-Wideband Microstrip Line Filters

This paper presents a computer-aided design procedure of simulated annealing algorithm to optimize dual-wideband microstrip line filters with symmetrical at least 500MHz bandwidths respectively. This method demonstrates the superiority of designing microstrip line dual-band filters. The value of characteristic impedances and electrical lengths of transmission lines synthesizing 2.4 GHz and 5.2 GHz dualband filters with a single input and a single output are adjusted to the annealing process by the optimization algorithm. The fabricated dual-wideband spectral transmittance and reflectance curves of these filters applying this method all effectively achieved desired high performances and resulted in a lower cost dual-band filters and open the way to commercial mass production. The method is applicable not only in 2.4 GHz and 5.2 GHz, but can be applied to any other multi-frequency bands.

Low Power VCO and Mixer for Computing Miracast and Mobile Bluetooth Applications

A new fully integrated, low power voltage controlled oscillator and divider for Bluetooth and Miracast application are presented. The power consumption use charge recycling technique to reduced current from the divider. This circuit was implemented in 0.18 um CMOS technique with 1.8 V supply voltage. The broadband CMOS double-balance mixer for RF receiver is presented. The broadband mixer is fabricated with the 0.18 μm CMOS process. Measurement of the CMOS mixer is performed; input return loss is higher than 8.5 dB. For VCO with divider measured results indicate the frequency is tunable from 1.91 GHz to 2.07 GHz, corresponding to 13 %. The phase noise of the VCO operating at 2 GHz is -116.8 dBc/Hz at 1 MHz offset, while the VCO draws 2.61 mA and 4.7 mW consumption at frequency band from a 1.8 V supply. Including pads. The output power is -15.85 dBm with 50- O termination at the frequency o f of 2 GHz and the calculated FOM (figure of merit) is -176.

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

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.

Integrated chip design of a 10GHz band voltage controlled oscillator and charge-injected mixer with low phase noise and wide tuning range.

A simple low phase noise and wide tuning range voltage-controlled oscillator (VCO) is designed for 10 GHz band application. The proposed oscillator adopts a complementary cross-coupled pair LC-VCO circuit with only one symmetrical inductor and implemented in TSMC 0.18-um CMOS process. A 10 GHz broadband CMOS double-balance mixer for communication receiver is presented. The broadband mixer is fabricated with low power 0.18 μm standard CMOS process. Measurement of the integrated mixer is performed as chipset input return loss is higher than 8.5 dB. At the supply voltage of 1.8 V, measured results achieve a tuning range of 9.6 to 11.08 GHz, corresponding to 13.9 %, a phase noise under -115.1 dBc/Hz at a 1 MHz offset frequency from 10.02 GHz with a tuned control voltage from 0 to 1.7 V and an output power of -2.231 dBm at 50-Ω termination and at 10.02 GHz. The power consumption is 3.58 mW and the chip area including pads is 0.61×0.66 (0.37) mm2. The proposed VCO, without the need of any off-chip device, is well suitable for mobile cellular networks applications.

Chip design of a high performance LC-VCO and mixer charge-injection signal processing for WiMAX communication and internet application

A high performance current-reused CMOS LC-voltage-controlled oscillator (LC-VCO) for WiMAX communication and internet application is fabricated in TSMC 0.18-μm CMOS process. The proposed VCO applies the complementary cross-coupled technique and uses differentially tuned accumulation MOS varactors. Measured results achieve 27.86% frequency tuned range when biased between 0-1.8 V, tunable output frequency from 2.81 to 3.71 GHz, output power of -5.54 dBm and phase noise of -122 dBc/Hz at 1 MHz offset from lower frequency of 2.816 GHz, and good value of FOM (Figure of Merit) of -180.8 dBc/Hz. The broadband CMOS double-balance mixer for wireless is presented. The broadband mixer is fabricated with the 0.18 μm CMOS process. Measurement of the CMOS mixer is performed, the input return loss is higher than 8.5 dB. The chip area including pads is only 0.488 mm2 and the power dissipation including buffers is 13.5 mW.