Abstract: A power combiner circuit comprises a network topology for broadband RF and microwave systems that includes coupling elements, internodal matching sections, and an output matching section. The network topology serves as a combining mechanism for power from multiple power amplifiers. The network topology is designed so that characteristic impedances of transmissions lines serving as the coupling elements, internodal matching sections, and an output matching section produce a load impedance at an output port that is matched to the impedances seen by each power amplifier providing power to the power combiner circuit. Such a network topology is scalable to an unlimited number of power amplifiers, and enables a desired broadband frequency response for power amplification, while realizing a very low level of power output loss between input and output ports.

Abstract: A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification. The semiconductor device can be configured by itself or with a complimentary device to form push-pull operations.

Abstract: A system and method is provided to compensate an amplifier circuit for changes in a load impedance in order to maintain a substantially optimum performance for the amplifier. More specifically, if the load impedance increases, then the amplifier is reconfigured to produce an output impedance that is likewise increased. One way of reconfiguring the amplifier for a load impedance increase is to increase the supply voltage to the device. The increase in the supply voltage to the device increases the rail to rail operation of the device. This would allow more dynamic range for the system performance. Assuming the current is substantially constant, the impedance seen the output of the amplifier will increase and be multiplied up to the impedance desired by the load resulting in a more optimum power transfer. Other parameters, such as the input drive and bias voltage to the amplifier can be changed in order to improve the performance of the amplifier.

Abstract: A four-way power combiner/splitter is disclosed that includes a first transmission line having a first non-grounding conductor and a first grounding conductor, wherein the first grounding conductor is grounded at a first end of the first transmission line. The combiner/splitter also has a second transmission line having a second non-grounding conductor and a second grounding conductor, wherein the second grounding conductor is grounded at a first end of the second transmission line. The non-grounding conductors of the first and second transmission lines are electrically coupled together at the respective first ends of the first and second transmission lines. An output/input port is provided that is electrically coupled to the first and second non-grounding conductors at the respective first ends of the first and second transmission lines.

Abstract: A field effect transistor is disclosed having a relatively high doped region (of the same type dopant as the channel) to reduce the change in the depletion region within the channel with changes in the drain voltage (Vd). Changes in the drain current (Id) with changes in the drain voltage (Vd) is a cause of non-linearity for traditional MOSFET. Because of the additional higher doped region provided in the channel, the depletion region within the higher doped region changes less with changes in the drain voltage (Vd). The higher doped region is situated near the top of the channel, where most of the drain current flows. Thus, the higher doped region dominates the drain current through the device. Since the drain current is less susceptible to changes in drain voltage (Vd), a more linear device results.

Abstract: A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification.

Abstract: A system and method is provided to compensate an amplifier circuit for changes in a load impedance in order to maintain a substantially optimum performance for the amplifier. More specifically, if the load impedance increases, then the amplifier is reconfigured to produce an output impedance that is likewise increased. One way of reconfiguring the amplifier for a load impedance increase is to increase the supply voltage to the device. The increase in the supply voltage to the device increases the rail to rail operation of the device. This would allow more dynamic range for the system performance. Assuming the current is substantially constant, the impedance seen the output of the amplifier will increase and be multiplied up to the impedance desired by the load resulting in a more optimum power transfer. Other parameters, such as the input drive and bias voltage to the amplifier can be changed in order to improve the performance of the amplifier.

Abstract: A semiconductor device that has a p-n junction with a photosensitive region partially having a diffusion region and a non-diffused region when the p-n junction is subjected to a reverse bias voltage. When an incident light (e.g. a laser) is directed at the surface of the photosensitive region, hole-electron pairs are generated in the partial diffusion region within the photosensitive region. As a result, the current through the photosensitive region changes in a substantially linear fashion with the intensity of the incident light. The semiconductor device can be configured in a circuit to provide substantially linear power amplification. The semiconductor device can be configured by itself or with a complimentary device to form push-pull operations.

Abstract: Methods and apparatus for the soft start of linear regulators for controlling inrush current. In linear regulators having a pass transistor controlled by a regulator control circuit, the regulator control circuit is disabled until the regulator output reaches a predetermined threshold level. On startup, an additional transistor is coupled with a resistor and capacitor to the control terminal of the pass transistor in such a way as to provide for the slow turn-on of the pass transistor. During this time, the control circuit for the pass transistor is held inoperative. After the regulator output reaches a predetermined threshold, the pass transistor control circuit becomes operative and the slow start circuitry becomes inoperative.

Abstract: The present invention is a method and apparatus for linearizing a non-linear portion of a first response of a power amplifier in response to an input signal over an operating range. A linearizing module preprocesses the input signal. The linearizing module provides a second response which is complementary to the first response in the non-linear portion of the first response. The power amplifier processes the preprocessed input signal to generate a result response which is linear over the operating range.

Abstract: Feed forward amplifiers and methods particularly suited for power multichannel microwave amplifiers for cellular phone base stations and the like. The input signal is modulated with a small percentage of modulation at a relatively low frequency before being amplified by the main amplifier. At the same time, the input signal is also coupled to provide inphase and quadrature components thereof to be mixed with the amplifier output and lowpass filtered to extract a component of the low frequency responsive to modulation components in the amplifier output due to the low frequency modulation.