Abstract: A radio frequency voltage controlled oscillator (RF VCO) includes a differential oscillator including two field effect transistors (FETs) in which an electric current flows laterally to a substrate and a current source including a bipolar transistor in which the electric current flows in a direction either perpendicular or lateral to the substrate from an emitter to a collector via a base. Therefore, 1/f noise is very small. Resultantly, the RF VCO using the bipolar junction transistor as the current source reduces the 1/f noise generated by the current source of a RF CMOS VCO and, ultimately, the phase noise of the VCO.

Abstract: A method and a system for calibrating an input voltage of a voltage controlled oscillator and a digital interface used for calibrating the input voltage. The method includes: setting a lock detection time for tuning a signal phase; setting a lock detection voltage section; setting output frequency values at predetermine spacings; checking connection states of capacitors of the capacitor bank necessary for a lock of the output frequency values; storing information regarding the connection states of the capacitors in the output frequency values; and if one of the output frequency values is determined depending on a change of a channel, setting connection states of the capacitors according to the information regarding the connection state corresponding to the one frequency value. The capacitor bank includes: a predetermined number of capacitors having different capacitances and connected to one another in parallel; and switches connected to the capacitors in series.

Abstract: A complementary metal oxide semiconductor voltage controlled oscillator is provided. The voltage controlled oscillator includes an LC tank which is supplied with a power supply voltage, the LC tank oscillating at a certain frequency; a negative resistor including first and second N-channel metal oxide semiconductor field effect transistors (NMOS FETs) to sustain the oscillation of the LC tank; a direct current block to remove a direct current component from the power supply voltage; an alternating current block to apply an alternating current voltage to the gates of the first and second NMOS FETs; a first current mirror including third and fourth NMOS FETs and allowing a current to symmetrically flow in the voltage controlled oscillator, a drain and the gate of the third NMOS FET being connected to a reference voltage supply; and the reference voltage supply applying a direct current voltage to the first current mirror.

Abstract: An MIM capacitor includes a substrate, a capacitor part having a structure in which a bottom electrode, a dielectric layer and a top electrode are laminated in order, and a ground shield layer formed between the bottom electrode of the capacitor part and the substrate and connected to a predetermined ground terminal. The ground shield layer may be formed of metal or polysilicon, or a layer doped with impurities having a valence of three or five. Also, the ground shield layer has a predetermined patterned structure. Thus, it is possible to minimize power loss due to the substrate.

Abstract: Disclosed is a dual-band voltage-controlled oscillator using bias switching and output-buffer multiplexing. The dual-band voltage-controlled oscillator includes a power supply unit for supplying a source voltage; plural voltage-controlled oscillation units for outputting different oscillation frequencies according to controls of a certain tuning voltage; plural bias units for generating driving voltages for driving the voltage-controlled oscillation units and supplying the driving voltages to the voltage-controlled oscillation units; and plural buffers for selectively outputting oscillation frequencies of the plural voltage-controlled oscillation units. The present invention implements the dual-band voltage-controlled oscillator through bias switching and output-buffer multiplexing, which brings an advantage of elimination of interference between output frequencies to enhance phase noise characteristics.

Abstract: A dual gate cascade amplifier includes a first transistor and a second transistor electrically connected in series, the second transistor including a first parallel transistor and a second parallel transistor, the first parallel transistor and the second parallel transistor being electrically connected in parallel, a first channel electrically connecting a first end channel region of the first transistor and a second end channel region, wherein one of the first or second end channel regions is a source and the other of the first or second end channel regions is a drain, the second end channel region being a common end channel region shared by the first and second parallel transistors, and a second channel electrically connected to the second end channel region and extending away from the first transistor.

Abstract: A radio frequency voltage controlled oscillator (RF VCO) includes a differential oscillator including two field effect transistors (FETs) in which an electric current flows laterally to a substrate and a current source including a bipolar transistor in which the electric current flows in a direction either perpendicular or lateral to the substrate from an emitter to a collector via a base. Therefore, 1/f noise is very small. Resultantly, the RF VCO using the bipolar junction transistor as the current source reduces the 1/f noise generated by the current source of a RF CMOS VCO and, ultimately, the phase noise of the VCO.

Abstract: In a structure of a radio frequency (RF) variable capacitor having a variable range of capacitance between a first minimum value and a first maximum value, and a method of manufacturing the structure, the structure includes a first capacitor, which has a variable range of capacitance between a second minimum value greater than the first minimum value and a second maximum value greater than the first maximum value, and a second capacitor, which is connected in series to the first capacitor and has a capacitance of a fixed value. By the structure and method, a quality factor of a radio frequency (RF) variable capacitor may be increased without adding complex processing steps.

Abstract: In a structure of a radio frequency (RF) variable capacitor having a variable range of capacitance between a first minimum value and a first maximum value, and a method of manufacturing the structure, the structure includes a first capacitor, which has a variable range of capacitance between a second minimum value greater than the first minimum value and a second maximum value greater than the first maximum value, and a second capacitor, which is connected in series to the first capacitor and has a capacitance of a fixed value. By the structure and method, a quality factor of a radio frequency (RF) variable capacitor may be increased without adding complex processing steps.

Abstract: A differential type VCO (Voltage Controllable Oscillator) is disclosed. The VCO has a differential amplifier having a couple of transistors and a couple of LC tanks. At each LC tank, a transformer is connected to form a buffer. An oscillating signal is output through the buffer with no power consumption. Additionally, a capacitor is connected to the secondary coil of the transformer to form a bandpass filter, thereby attenuating a harmonic signal included in the oscillating signal.

Abstract: A differential type VCO (Voltage Controllable Oscillator) is disclosed. The VCO has a differential amplifier having a couple of transistors and a couple of LC tanks. At each LC tank, a transformer is connected to form a buffer. An oscillating signal is output through the buffer with no power consumption. Additionally, a capacitor is connected to the secondary coil of the transformer to form a bandpass filter, thereby attenuating a harmonic signal included in the oscillating signal.