Patent application number | Description | Published |
20100033241 | HIGH FREQUENCY AMPLIFIER - Provided is a high frequency amplifier including two amplifying elements of different element sizes connected in parallel and switching the amplifying elements in accordance with a level of output power. In particular, the high frequency amplifier includes an output matching circuit for matching to characteristic impedance (50 ohms) both when the output power is high and low, and increasing impedance when the turned-off amplifying element is viewed from a connection node on an output side of the two amplifying elements. Consequently, characteristics such as high output power and high efficiency can be achieved and it is possible to prevent an amplified high frequency signal from passing around to a matching circuit on a turned-off amplifying element side. | 02-11-2010 |
20120293257 | HIGH FREQUENCY POWER AMPLIFIER - A high frequency power amplifier includes: a first transistor for amplifying an input high-frequency signal; a second transistor for amplifying an output signal of the first transistor; a third transistor connected in parallel with the first transistor and for amplifying the input high-frequency signal; a first switching element connected between an output of the first transistor and an input of the second transistor; a second switching element connected between an output of the third transistor and the first switching element; third and fourth switching elements connected in series between the output of the first transistor and an output of the second transistor, and between the second switching element and the output of the second transistor; and a first capacitor connected between the third switching element and the fourth switching element. | 11-22-2012 |
20130113561 | OUTPUT MODE SWITCHING AMPLIFIER - An output mode switching amplifier, including: a transistor for signal amplification connected between a first node on an input side and a second node on an output side; a bypass path for bypassing the transistor between the first node and the second node; a voltage control circuit for switching whether to apply a bias voltage to the transistor so that a transmission signal is amplified by the transistor or to output a transmission signal via the bypass path without amplifying the transmission signal by the transistor; and a second-harmonic reflection circuit connected to the bypass path, for reflecting a second harmonic of the transmission signal. | 05-09-2013 |
20130241659 | POWER AMPLIFIER - A power amplifier includes: a first amplifying element amplifying an input signal; a second amplifying element amplifying an output signal of the first amplifying element; a third amplifying element amplifying the input signal; a first switch connected between an output of the first amplifying element and an input of second amplifying element; a second switch connected between an output of the first amplifying element and an output of the third amplifying element; a third switch connected between an output of the first amplifying element and an output of the second amplifying element; a reference voltage generating a circuit generating reference voltage; a bias circuit supplying a bias current, based on the reference voltage, to inputs of the first, second, and third amplifying elements; and a control circuit controlling the first, second and third switches and the reference voltage generating circuit. | 09-19-2013 |
20130249626 | MULTIPLE POWER MODE AMPLIFIER - A multiple power mode amplifier includes: N amplifiers connected in series via switches; and a control circuit for controlling the N amplifiers in accordance with the output modes. P amplifiers out of the N amplifiers constitute a driver amplifier, and constitute a negative feedback amplifier including a feedback circuit for negatively feeding back its own output signal to its own input side. N−P amplifiers constitute a final stage amplifier connected in series to the negative feedback amplifier in a disconnectable manner. The control circuit is configured to: in a first output mode, disconnect the final stage amplifier from the negative feedback amplifier, and disable the feedback circuit; and in a second output mode, connect the final stage amplifier in series to the negative feedback amplifier, and enable the feedback circuit. | 09-26-2013 |
20140070890 | POWER AMPLIFIER - A power amplifier includes: an amplification element amplifying an input signal; and a bias circuit supplying a bias current to an input of the amplification element. The bias circuit includes a reference voltage terminal to which a battery voltage is applied from a battery, a first resistor having a first end connected to the reference voltage terminal, a second resistor connected between a second end of the first resistor and ground, and a first transistor. The first transistor has a control terminal connected to a connection point between the first resistor and the second resistor, a first terminal connected to a power supply, and a second terminal connected to the input of the amplification element. The first and second resistors are the same material. | 03-13-2014 |
20140292439 | DIRECTIONAL COUPLER - Disclosed is a directional coupler including a broadside coupled line | 10-02-2014 |
20140292440 | DIRECTIONAL COUPLER - Disclosed is a directional coupler including a first hollow portion | 10-02-2014 |
20150070096 | POWER AMPLIFIER - A power amplifier is smaller in size and limits input noise having a differential frequency. A power amplifier has an input terminal, an amplifying transistor, a bias circuit, a filter circuit, and an impedance matching circuit. The bias circuit supplies a bias to the signal input side of the amplifying transistor. The filter circuit removes noise at the signal input side of the amplifying transistor. The filter circuit has a matching resistor, a chip inductor, and a chip capacitor. Each of the chip inductor and the chip capacitor is a surface mount device. The matching resistor is located on a semiconductor substrate, has a first end connected to a connection point of two MIM capacitors, and a second end connected to a connection point of one of the MIM capacitors and the signal input side of the amplifying transistor. | 03-12-2015 |