Abstract: Disclosed is a power loss protection integrated circuit. In the power loss protection integrated circuit, an interrupt device is arranged on an electrical path between an output terminal of a buck converter and a low voltage capacitor such that a flow of current to the low voltage capacitor is limited upon initial operation to ensure stability of an output voltage of the buck converter, and after the passage of a predetermined time, the interrupt device is fully turned on when a voltage of the low voltage capacitor is almost the same as the output voltage of the buck converter such that the voltage of the low voltage capacitor is electrically connected to the output voltage of the buck converter.

Abstract: The present invention relates to a direct current/direct current (DC/DC) converter. According to the present invention, output ends of a plurality of converter circuits, each having two switches in a single fabricated integrated circuit (IC), are integrated by selectively connecting them to each other in the outside depending on the amount of current required for operation of the IC. Therefore, the DC/DC converter can operate with maximum efficiency in various user-desired load current ranges.

Abstract: Disclosed is a power loss protection integrated circuit. According to one embodiment, the power loss protection integrated circuit includes a buck/boost converter controller that operates in buck mode in a normal power supply state such that a portion of the power is used to store energy in a low voltage capacitor and operates in boost mode when the power supply is cut off such that the energy charged in the low voltage capacitor is utilized to supply emergency power to a main system.

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: 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.