Samsung Electro-mechanics Co., Ltd.

Hyeon Seok Hwang

Yoo Sam Na

Byeong Hak Jo

Moon Suk Jeong

Gyu Suck Kim

Moon Sun Kim

Jung Chul Gong

Hyun Paek

Seung Min Oh

Kyoung Soo Kwon

Kyoung Seok Park

Shin Hwan Hwang

Sang Suk Kim

Geun Yong Lee

Young Sik Hur

Yoo Hwan Kim

Hyun Hwan Yoo

Hyun Jin Yoo

Gyu Sub Kim

Seung Chul Pyo

Seong Geun Kim

Jong Soo Lee

Seung Chui Pyo

Su Syeong Kim

Ju Yeon Lee

Sun Hong Kim

Si Heon Kwak

Su Gyeong Kim

Disclosed herein are a transformer and a method of manufacturing the same. The transformer includes: a primary side winding having a loop shape; a secondary side winding formed on the same plane as that of the primary side winding in a remaining section except for at least a section at which it intersects with the primary side winding and having the same loop shape as that of the primary side winding so as to be electromagnetically coupled to the primary side winding; and an intersecting section formed so that the primary side and secondary side windings having the sum of the turn numbers of 3 or more intersect with each other in a two-layer structure, wherein the intersecting section includes at least one point of intermediate node having one side connected in a first layer and the other side connected in a second layer.

Transformer and method of manufacturing the same

An apparatus for switching a transmission route of a radio frequency signal is provided. The apparatus may include a first inductor electrically connected to first and second ports; a second inductor electrically connected to the third and fourth ports and disposed to have mutual inductance with the first inductor; first, second, third, and fourth switches configured to switch an electrical connection between the first, second, third, and fourth ports and a ground, respectively; wherein the first and second inductors are electrically connected to the ground through one of the first and second switches and one of the third and fourth switches such that a radio frequency signal pass between one of the first and second ports an one of the third and fourth ports.

Apparatus with transmission route switching of radio frequency signals and radio frequency module

A bias circuit includes a bias current circuit and a temperature compensation circuit. The bias current circuit includes a first resistor and a first transistor, in a first current path connected between a current terminal of a reference current and a ground, and connected to each other in series, and a second transistor in a second current path connected between the current terminal and the ground, and having a base connected to a collector of the first transistor. The temperature compensation circuit includes a second resistor in the second current path, and connected between an emitter of the second transistor and a base of the first transistor and having a first thermal coefficient, and a third resistor included in the second current path, and connected between the base of the first transistor and the ground and having a second thermal coefficient, different from the first thermal coefficient.

Bias circuit and amplifying device having temperature compensation function

A band selection switch circuit for an amplifier with an impedance matching circuit includes a band selection switch and an impedance compensation circuit. The band selection switch includes a signal port switch configured to selectively connect to one of a common transmit port, transmit and receive (TxRx) ports, and receive ports, and an impedance port switch configured to selectively connect the common transmit port and one of the receive ports and an impedance port. The impedance compensation circuit includes an impedance element connected to the impedance port.

Band selection switch circuit and amplifier

A power amplifier includes an amplifying circuit configured to amplify an input signal and comprising transistors, which may be disposed in parallel with one another and divided into a first group of transistors and a second group of transistors. The power amplifier also includes a bias circuit configured to supply bias power to one of the transistors of the first group and the transistors of the second group.

Power amplifier

Disclosed herein is a circuit for preventing an element from being damaged although output impedance of a final transistor is changed in a power amplifier. The power amplifier includes: a power stage amplifying a signal; a transformer connected to an output terminal of the power stage and coupling a signal output from the power stage; and a controller controlling a bias voltage from the power stage according to the coupled signal. Although output impedance is changed, damage to the power amplifier can be prevented. Also, the power amplifier can be automatically controlled to maintain performance thereof by sensing an operational state in which output impedance is normal.

There is provided a complementary metal oxide semiconductor (CMOS) power amplifier including: a load unit connected between an operating voltage supply terminal and an output terminal; an amplifying unit formed as a cascode structure between the load unit and a ground, amplifying a power of an input signal input through an input terminal and outputting the amplified signal through an output terminal; and a threshold voltage control unit varying a threshold voltage of the amplifying unit according to a magnitude of the input signal input through the input terminal.

Disclosed herein is a power amplifier. The power amplifier includes a first common source transistor for amplifying an input signal into a predetermined level, a second common source transistor for compensating for input capacitance and performing auxiliary amplification for the first common source transistor, and a common gate transistor connected to the first common source transistor in a cascode structure, configured to be connected in parallel to the second common source transistor and prevent the first common source transistor from breaking down, and configured to output a signal amplified by a value obtained by adding the gain of the first common source transistor and the gain of the second common source transistor to each other.

Power amplifier break down characteristic

A frequency conversion circuit comprises an input stage composed of one or more transistors, the input stage outputting a current corresponding to a voltage-type RF signal which is input to the gate of the transistor; a frequency conversion stage receiving an LO signal, causing the output RF signal to transit by the frequency of the LO signal so as to output an IF signal, and detecting an output voltage of the IF signal; a bleeding transistor connected to the input stage, supplying a current corresponding to a DC voltage, applied to a gate-source stage thereof, as a bleeding current to the transistor of the input stage, and in an AC manner, operating complementarily with the input stage to control a current flowing in the frequency conversion stage; a common mode feedback circuit comparing an output voltage provided from the frequency conversion stage with a preset reference voltage, adjusting the output voltage such that the output voltage is equalized to the reference voltage, and directly feeding the adjusted output voltage to the bleeding transistor; and a load stage composed of resistors and distributing a power supply voltage to apply to the frequency conversion stage.

Frequency conversion circuit

There is provided an active balun circuit including: a load circuit unit including a first and a second load; a differential amplifying unit including a first amplifying unit connected to the first load, and a second amplifying unit connected to the second load and forming a differential amplifying unit together with the first amplifying unit, the differential amplifying unit differentially amplifying an input signal, and outputting first and second output signals out-of-phase with each other through first and second output terminals, respectively; a current source connected between a ground and a common connection node of the first and second amplifying units, and maintaining a constant amount of current flowing through the differential amplifying unit; and a compensation amplifying unit amplifying the input signal supplied through the input terminal, transmitting the amplified input signal to the second amplifying unit, and rejecting common mode noise of the differential amplifying unit.

Active balun circuit

There is provided a bias current generating apparatus capable of providing a bias current where a characteristic change is compensated, to one of an analog circuit and RF circuit where various characteristic changes occur according to a temperature, by generating bias currents having a plurality of temperature coefficients. The apparatus includes: a positive temperature coefficient current generator generating a positive temperature coefficient current in direct proportion to an absolute temperature; a zero temperature coefficient current generator generating a zero temperature coefficient current constant regardless of the absolute temperature; and an adjustable temperature coefficient current generator generating and outputting an adjustable temperature coefficient current by amplifying the positive temperature coefficient current by A times, amplifying the zero temperature coefficient current by B times, adding the two amplified temperature coefficient currents, wherein a temperature coefficient of the adjustable temperature coefficient current is varied by adjusting sizes of the A and B.

Bias current generating apparatus with adjustable temperature coefficient

There is provided a step attenuator having two Pi-type attenuators and one bridged-T type attenuator that share some resistors. The step attenuator is used to prevent a reduction in frequency range caused by use of MOS transistors and reduce attenuation of signal power and frequency band by the MOS transistors, thereby obtaining a low attenuation value and reducing input and output mismatch.

Step attenuator

A circuit for compensating for an offset voltage in a PhotoDetector Integrated Circuit (PDIC). The circuit includes a temperature detection unit, a current transfer unit and a current adjustment unit. The temperature detection unit generates a current that varies with variation in surrounding temperature. The current transfer unit transfers the generated current. The current adjustment unit adjusts the current transferred from the current transfer unit at a predetermined ratio and outputs the adjusted current.

Circuit and method for compensating for offset voltage

Disclosed herein is a PhotoDiode Integrated Circuit (PDIC) having multiple gain states. The PDIC includes a current-voltage conversion unit, an input amplification stage circuit, a reference resistance unit, a feedback resistance unit, and a switching unit. The current-voltage conversion unit converts a current signal into a voltage signal. The input amplification stage circuit is connected to the current-voltage conversion unit to receive and amplify the voltage signal. The reference resistance unit is connected to the second input terminal of the input amplification stage circuit. The output amplification stage circuit is connected to the output terminal of the input amplification stage circuit. The feedback resistance unit is connected in parallel between the second input terminal and the output terminal of the output amplification stage circuit, and is configured to have a plurality of resistance elements. The switching unit selectively connects the plurality of resistance elements.

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Seoul, South Korea

Hyeon Seok Hwang