Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.

Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is place at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.

Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.

Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is place at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.

Abstract: The present invention provides a communication terminal that enables precise communications with optimum receive sensitivity at any time regardless of any change in peripheral environments of an antenna thereof. The communication terminal including means for transmitting and receiving radio waves is provided with a training mechanism for enabling the communication terminal itself to conduct training mode for tuning receive sensitivity, and switching mechanism for switching between normal communication mode and the training mode. The communication terminal is particularly useful as a communication terminal for automobile in the Intelligent Transport System or the like.

Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.

Abstract: A maintenance terminal for a disk array device is provided which can make setting of the disk array device and can easily confirm the setting contents. The maintenance terminal for the disk array device has three jumper connectors as setting terminals into which a conduction pin is inserted. The maintenance terminal also has eight light emitting diodes disposed in two rows and being capable of turning on and off in correspondence with a setting state of the disk array device in a network selectively changed through insertion of the conduction pin into the setting terminals.

Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.

Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is placed at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.

Abstract: The present invention provides a radio frequency power amplifier which may not introduce radio frequency loss during switching power amplifier units between high and low output power levels. By connecting a first-stage matching network M12 and first-stage matching network M13 to respective output nodes of a power amplifier unit A11 and power amplifier unit A12 that either one operate by switching, connecting the output nodes of the first-stage matching network M12 and M13 in parallel, connecting a last-stage matching network M11 between the junction of M12 and M13 and the output terminal OUT, the first-stage matching networks M12, M13, and last-stage matching network M11 are formed, for both power amplifier units A11 and A12, so that impedance matching is established between the output terminal OUT and the power amplifier unit in operation when one unit is in operation the other is in stop of operation.

Abstract: In a mobile telephone apparatus corresponding to dual-band provided with an RF power module to operate in two kinds of different frequencies, a common harmonics control circuit is provided to the output circuit of such RF power module to realize higher efficiency in view of controlling respective harmonics power for both band frequencies. Moreover, a means for selectively setting the bias is also provided so that the maximum efficiency can be attained depending on the output power required with respective communication systems with the bias control signal output from the CPU of the control unit interlocking with selection of frequency of the mobile telephone apparatus body.

Abstract: A high frequency communication device which can reduce undesired electromagnetic coupling inside and outside a box thereof in which circuit parts constituting a transmitter-receiver circuit are contained. Periodic structures (6) are provided on at least a part of a wall constituting a box (1, 4, 5) so that the periodic structures (6) serve as a filter which has a non-propagating frequency band corresponding a frequency band covering an undesired electromagnetic emission inside the box. Thus, undesired electromagnetic emission energy from any electromagnetic emission source can be confined locally to prevent a possible problem of electromagnetic interference.

Abstract: To provide a high frequency amplifying apparatus for reducing a phase change caused in switching to a different output level, a variable phase shifter is provided at at least one location of respective paths rearward from a branching circuit for switching a path on a high output side having an amplifier using a first semiconductor device at an output stage and a path on a low output side having an amplifier using a second semiconductor device with a smaller output than the first semiconductor device on an output stage in accordance with a desired output level. After branching and a phase length of the variable phase shifter is set to a pre-determined value such that passing phase lengths of the respective paths become substantially the same by passing either of the paths.

Abstract: A power amplifier module is provided with a function of protecting an amplifying device against destruction caused by a standing wave by reflection from an antenna end in load variation. Increase in base current from idling current of a final stage amplifying portion GaAs-HBT in load variation is detected and canceled and collector current is restrained to thereby prevent an increase in output and prevent destruction of GaAs-RET. By also using a function of successively lowering idling current when power source voltage is elevated and a clipping function of diodes connected in parallel with output stage GaAs-RET, voltage as well as current more than necessary are avoided from being applied on the output stage GaAs-RET.

Abstract: Apparatus including input ports for inputting a plurality of input signals different in frequency of carrier from one another, dividers for respectively dividing each of the plurality of input signals inputted to the input ports into plural form, and phase shifters for respectively assigning a weight of phase to each of divided signals corresponding to a number obtained by subtracting 1 from the number of divisions. A plurality of first combiners are provided for respectively adding up the signals different in the frequency of carrier, out of the divided signals and signals each assigned the weight of phase, a plurality of amplifiers are provided for respectively amplifying signals outputted from the plurality of first combiners, and a second combiner is provided for adding signals outputted from the plurality of amplifiers to output one signal.

Abstract: To provide a small-sized high frequency power amplifier for preventing oscillation by a small number of switching circuits and outputting high power and low power with high efficiencies, a high frequency power amplifier module and a portable telephone, the high frequency power amplifier is constituted by an amplifying circuit A and an amplifying circuit B connected in parallel, a size of a transistor at an output stage of the amplifying circuit B is made to be equal to or smaller than ¼ of a size of a transistor of an output stage of the amplifying circuit A and a switching circuit is connected between a signal line forward from the output stage of the amplifying circuit A and a ground terminal.

Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is placed at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.

Abstract: In a radio frequency amplifier, a value of a matching device is changed in one matching circuit so as to constitute a matching circuit which realizes a load impedance optimized by a plurality of frequency bands, outputs, and signal modulation systems. When the matching device value is changed, a plurality of devices are connected onto the matching circuit via a micro mechanical switch. Alternatively, two points disposed apart from each other on a transmission line are connected using a micro mechanical switch. The micro mechanical switch is controlled to be on/off so that a device value or transmission line length is changed.

Abstract: A radio frequency module includes a first circuit board and a second circuit board. A first circuit element group is placed in a cavity formed on the upper surface of the first circuit board, and a second circuit element group is placed on the upper surface of the second circuit board. The first and second circuit boards are provided with terminal electrodes by which electrical connection is established. The radio frequency module is formed by vertically connecting the two circuit boards together. Heat emitted by the first circuit element group is transferred to a heat radiation section, which is formed on the lower surface of the first circuit board, via through-holes connecting the bottom of the cavity with the heat radiation section.

Abstract: A radio frequency power amplifier module for a dual-band type mobile communication apparatus that can transmit and receive a first frequency f1 and second frequency f2 (f2=2×f1). It includes a drive stage amplifier having the gain peaks at f1 and f2 with a matching circuit and a radio frequency power output circuit including a radio frequency power output transistor. The output circuit has a transmission line connected to the drain end of the output transistor, a parallel resonance circuit connected in series to the transmission line to resonate at harmonics of a frequency twice the frequency f2, a series resonance circuit provided between one end of the resonance circuit and the ground to resonate at harmonics of a frequency twice the frequency f2 and an output matching circuit provided in series to the other end of the parallel resonance circuit for matching with f1 and f2.