摘要:
The present invention provides a digital amplitude modulator and polar transmitter using the same. The polar transmitter includes: a polar converter for converting an input signal into an amplitude information signal and a phase information signal, and outputting the converted amplitude and phase information signal; a sigma-delta modulator for receiving a fractional part of the amplitude information signal, and generating a correcting value for an integer part of the amplitude information signal; a phase-modulator for upward-modulating the phase information signal outputted from the polar converter, and outputting carrier waves including the upward-modulated phase information signal; and a digital power amplifier for generating an output signal whose amplitude corresponds to the integer part of the amplitude information signal which is subjected to correction by the correcting value, and outputting combining the output signal with an output value of the phase-modulator to output the combined signal.
摘要:
There is provided a regulator with soft-start using a current source. The regulator with soft-start may include: a power switch unit including first and second power switches connected between a power supply terminal and an output terminal; a load capacitor connected between the output terminal and a ground; a voltage detection unit detecting a voltage of the output terminal; a comparison unit comparing a detection voltage and a predetermined reference voltage, and outputting first and second switching signals; a current generating a predetermined constant current; a current control unit switching a connection between a control terminal of the first power switch and the current source unit according to the first switching, and switching a connection between the control terminal of the first power switch and the ground according to the second switching signal; and an error amplification unit amplifying an error voltage between the detection.
摘要:
There is disclosed a voltage regulating apparatus with a short settling time and a small current consumption. The voltage regulating apparatus comprises a reference voltage generator including an MOSFET array comprising a plurality of MOSFETs with a structure in which a drain and a source are connected in series with each other, a supply voltage is applied to the drain of the MOSFET located in an end of the MOSFET array and the source of the MOSFET located in another end is grounded, and the reference voltage is a voltage obtained by dividing by the plurality of MOSFETs of the MOSFET array at a predetermined ratio.
摘要:
The present invention relates to a broadband voltage controlled oscillator and a method for generating a broadband oscillation frequency; and, more particularly, to a broadband voltage controlled oscillator and a method for generating a broadband oscillation frequency capable of operating over a wide frequency band by including a weighted current cell to select two frequency band modes, generating various levels of total 64 oscillation frequencies by including a variable frequency tank and a capacitor bank, and further facilitating adjustment of the total 64 oscillation frequencies distributed over the wide frequency band by including a control signal generator for generating control signals each of which is applied to the weighted current cell, the variable frequency tank and the capacitor bank by a BDD(Binary Decision Diagram) technique.
摘要:
Provided is a low-power ZigBee device provided with a sleeping mode and an active mode including a power supplying unit for supplying a power; a Medium Access Control (MAC) processing unit for receiving a wake-up packet and for controlling a modem unit and an Radio Frequency (RF) unit; and a Central Processing Unit (CPU) for receiving and processing a data packet, wherein the MAC processing unit makes the power supplying unit apply a power to the CPU based on a result of checking an identification (ID) of the wake-up packet.
摘要:
In a key scanning circuit, a key input unit has a parallel connection of a plurality of circuits having a series connection of resistors and switches between a power supply input terminal and a key scanning terminal. The resistors connected in parallel have different resistances. A current mirror has a first terminal connected to the key scanning terminal. A reference current source is connected between a second terminal of the current mirror and the power supply input terminal.
摘要:
Provided is a showerhead that can inject a reaction gas into a reaction chamber in a manner such that the injected reaction gas form a spiral vortex flow field. Therefore, the injected reaction gas can be mixed within a shorter distance, and thus the effective deposition radius of a wafer can be increased so that uniform-density deposition can be performed on the entire surface of the wafer using the mixed reaction gas.
摘要:
There is provided a regulator with soft-start using a current source. The regulator with soft-start may include: a power switch unit including first and second power switches connected between a power supply terminal and an output terminal; a load capacitor connected between the output terminal and a ground; a voltage detection unit detecting a voltage of the output terminal; a comparison unit comparing a detection voltage and a predetermined reference voltage, and outputting first and second switching signals; a current generating a predetermined constant current; a current control unit switching a connection between a control terminal of the first power switch and the current source unit according to the first switching, and switching a connection between the control terminal of the first power switch and the ground according to the second switching signal; and an error amplification unit amplifying an error voltage between the detection.
摘要:
An antenna diversity receiver includes a plurality of antennas, an antenna selector unit, an RF module unit, a logic gate unit, a power detector unit, and a selection controller unit. The antenna selector unit selects one of the antennas. The RF module unit converts an RF RX signal received from the antenna selector unit into a baseband RX signal. The logic gate unit controls a power detection mode for detecting the power levels of RX signals and an operation mode for selecting one of the antennas. The power detector unit detects the power level of the RX signal. The selection controller unit controls the antenna selector unit to sequentially select the antennas in the power detection mode, and controls the antenna selector unit to select the antenna with a relatively good RX sensitivity among the antennas.
摘要:
Provided is an apparatus for controlling lighting brightness through PFM, the apparatus including a lighting control unit that generates a control signal for controlling the brightness of a plurality of lightings; a PFM signal generating unit that is controlled by the control signal so as to generate a plurality of PFM signals having a different frequency from each other; and a driving voltage generating unit that composes the generated PFM signals in accordance with a preset combination, thereby generating driving voltages for driving the lightings.