Abstract: There is provided a power amplifier circuit capable of improving cross isolation between a high frequency band power coupler and a low frequency band power coupler, by directly transmitting power to the high frequency band power coupler and the low frequency band power coupler from a power amplifier, and forming a predetermined inductance circuit or an LC resonance circuit in a line transmitting the power to the high frequency band power coupler. The power amplifier circuit may include a power amplifying unit supplied with power from the outside and amplifying an input signal, a coupling unit having a high frequency band power coupler and a low frequency band power coupler, and an isolation unit including a first power line and a second power line, wherein the first power line has an inductor blocking signal interference generated in a predetermined frequency band.

Abstract: A CMOS power amplifier includes: a first MOS transistor connected between a first power terminal and a first output stage and having a gate connected to an input stage; a second MOS transistor connected between the first output stage and a ground and having a gate connected to the input stage; a switching circuit unit connecting or separating a feedback line between the input stage and the first output stage to select a linear amplifying operation or a non-linear amplifying operation; and a resistor formed at the feedback line between the input stage and the first output stage to determine a linear amplification gain when the feedback line is turned on.

Abstract: A transformer includes at least one input conductive line having both ends provided as input ports of a positive (+) signal and a negative (?) signal, respectively, one output conductive line disposed adjacent to the at least one input conductive line to be electromagnetically coupled to the at least one input conductive line, and having a first end connected to a ground, a first resonator disposed between a second end of the output conductive line and the ground, a second resonator having a first end connected to the second end of the output conductive line and a second end provided as an output port, and a third resonator connected in series between the first end of the output conductive line and the ground.

Abstract: A power amplifier includes an inverter amplification section configured to amplify AC components and remove DC components from at least one input signal, an impedance matching section configured to match an impedance of a transmission path of the at least one input signal amplified by the inverter amplification section, and an amplification section configured to amplify an impedance-matched signal from the impedance matching section according to a predetermined gain. The inverter amplification section includes at least one P-channel metal-oxide semiconductor field effect transistor (MOS FET) having a gate configured to receive the at least one input signal and at least one N-channel MOS FET having a gate configured to receive the at least one input signal. The at least one P-channel MOS FET and the at least one N-channel MOS FET are serially connected.

Abstract: A Tx module includes a plurality of power amplification units, a plurality of matching circuit units configured as transformers having input ports connected to output ports of the plurality of power amplification units, respectively, and a plurality of harmonic filter units having input ports connected to output ports of the plurality of matching circuit units, respectively. At least one of the matching circuit units includes a plurality of primary windings connected to output ports of corresponding power amplifiers of the power amplification units and a secondary winding inductively coupled in common to the plurality of primary windings.

Abstract: A transformer having a structure in which first and second substrates are vertically laminated, including: a plurality of input conductive lines disposed on the first substrate along a circumference thereof; a single output conductive line disposed co-planarly with the plurality of input conductive lines, and having one end connected to a ground; and an air bridge including a pair of conductive via holes formed in any one conductive line in an overlapped area in which the input and output conductive lines are intersected with each other to penetrate through the first substrate and a single piece of conductive line connecting the pair of conductive via holes to each other and disposed on the second substrate, thereby preventing a short-circuit between the input and output conductive lines.

Abstract: There is provided a power amplifier circuit capable of improving cross isolation between a high frequency band power coupler and a low frequency band power coupler, by directly transmitting power to the high frequency band power coupler and the low frequency band power coupler from a power amplifier, and forming a predetermined inductance circuit or an LC resonance circuit in a line transmitting the power to the high frequency band power coupler. The power amplifier circuit may include a power amplifying unit supplied with power from the outside and amplifying an input signal, a coupling unit having a high frequency band power coupler and a low frequency band power coupler, and an isolation unit including a first power line and a second power line, wherein the first power line has an inductor blocking signal interference generated in a predetermined frequency band.

Abstract: A CMOS power amplifier includes: a first MOS transistor connected between a first power terminal and a first output stage and having a gate connected to an input stage; a second MOS transistor connected between the first output stage and a ground and having a gate connected to the input stage; a switching circuit unit connecting or separating a feedback line between the input stage and the first output stage to select a linear amplifying operation or a non-linear amplifying operation; and a resistor formed at the feedback line between the input stage and the first output stage to determine a linear amplification gain when the feedback line is turned on.

Abstract: Disclosed herein is a power amplifier. The power amplifier includes N power amplification means, a transformer, and a harmonic elimination unit. Each of the N power amplification means amplifies an input signal into a predetermined level. The transformer includes N/2 primary windings respectively connected to the output terminals of the power amplification means and a secondary winding configured such that coil elements are connected in series between an output terminal and a ground, and sums power transmitted from the primary windings. The harmonic elimination unit is disposed across both ends of the secondary winding of the transformer, and eliminates the output of the harmonic frequencies of a preset frequency.

Abstract: There is provided a multi-stage CMOS power amplifier including: a driver amplifier having differential output terminals, inverting differential signals input through first and second input terminals and outputting the respective inverted signals through the differential output terminals; a transformer for power matching having a primary coil connected between the differential output terminals of the driver amplifier and a secondary coil coupled with the primary coil using electromagnetic induction, having a predetermined turns ratio to the primary coil, and connected to a direct current (DC) tuning voltage terminal; and a power amplifier power-amplifying differential signals passing through one end and the other end of the secondary coil of the transformer and outputting the respective power-amplified differential signals through first and second output terminals.

Abstract: Disclosed herein is a power amplifier. The power amplifier includes N power amplification means, a transformer, and a harmonic elimination unit. Each of the N power amplification means amplifies an input signal into a predetermined level. The transformer includes N/2 primary windings respectively connected to the output terminals of the power amplification means and a secondary winding configured such that coil elements are connected in series between an output terminal and a ground, and sums power transmitted from the primary windings. The harmonic elimination unit is disposed across both ends of the secondary winding of the transformer, and eliminates the output of the harmonic frequencies of a preset frequency.

Abstract: A power amplifier system with power control function provides accurate and efficient power control by controlling a bias voltage and a bias current of the power amplifier at the same time.

Abstract: There is provided a voltage regulator suitable for a CMOS circuit. A voltage regulator suitable for a CMOS circuit according to an aspect of the invention may include: a voltage setting unit setting a voltage across both terminals of a load; a voltage amplification unit setting an input voltage; and a voltage control unit controlling a voltage to be applied to the second connection node according to an output voltage of the voltage amplification unit, wherein the voltage across both terminals of the load is maintained to be constant regardless of variations in a power voltage.

Abstract: There is provided a power amplifier that can increase power efficiency by preventing power consumption caused by DC components from an RF input signal. A power amplifier according to an aspect of the invention may include: an inverter amplification section amplifying an input signal according to an inverter method to thereby remove DC components from the input signal; an impedance matching section matching an impedance of a transmission path of the input signal amplified by the inverter amplification section; and an amplification section amplifying an impedance-matched signal from the impedance matching section according to a gain set beforehand.

Abstract: There is provided a multi-stage CMOS power amplifier including: a driver amplifier having differential output terminals, inverting differential signals input through first and second input terminals and outputting the respective inverted signals through the differential output terminals; a transformer for power matching having a primary coil connected between the differential output terminals of the driver amplifier and a secondary coil coupled with the primary coil using electromagnetic induction, having a predetermined turns ratio to the primary coil, and connected to a direct current (DC) tuning voltage terminal; and a power amplifier power-amplifying differential signals passing through one end and the other end of the secondary coil of the transformer and outputting the respective power-amplified differential signals through first and second output terminals.

Abstract: A power amplifier system with power control function provides accurate and efficient power control by controlling a bias voltage and a bias current of the power amplifier at the same time.

Abstract: A transformer includes at least one input conductive line having both ends provided as input ports of a positive (+) signal and a negative (?) signal, respectively, one output conductive line disposed adjacent to the at least one input conductive line to be electromagnetically coupled to the at least one input conductive line, and having one end connected to the ground, a first resonator disposed between the other end of the output conductive line and the ground, and a second resonator having one end connected to the other end of the output conductive line and the other end provided as an output port.

Abstract: A Tx module for wireless communications includes a plurality of Tx signal input ports receiving Tx signals of different frequencies, respectively, a plurality of power amplification units having input ports connected to the plurality of Tx signal input ports, respectively, a plurality of matching circuit units configured as transformers having input ports connected to output ports of the plurality of power amplification units, respectively, a plurality of harmonic filter units having input ports connected to output ports of the plurality of matching circuit units, respectively, a switch unit having input ports connected to output ports of the plurality of harmonic filter units, respectively and selecting one of signals input through the input ports as output, a gain/switching control unit controlling gains of the power amplification units and controlling the output selection of the switch unit, and a Tx signal output port connected to an output port of the switch unit.