Macom Technology Solutions Holdings, Inc.

Rf Micro Devices, Inc.

Fujitsu Compound Semiconductor, Inc.

Fujitsu Corporation

Avantek, Inc.

Wayne Kennan

Duy Nguyen

Baotoan Nguyen

Marcus Granger-Jones

Henrik Morkner

R Steven Brozovich

Edmar Camargo

Stefano D'Agostino

Toshi Omori

Trong Phan

Nguyen Nguyen

Thanh Pham

A distributed amplifier system comprising an impedance matching network configured to match an input impedance to an output impedance of the signal source, and a DC block configured to block DC components in the input signal. A variable gain amplifier adjusts the gain applied to the input signal based on a gain control signal to generate a gain adjusted signal. An emitter follower circuit receives and processes the gain adjusted signal to introduce gain peaking to create a modified signal. A distributed amplifier receives and amplifies the modified signal from the emitter follower circuit, to create an amplified signal. The distributed amplifier includes a termination network and one or more impedance matching elements configured for gain shaping the amplified signal. The gain peaking introduced by the emitter follower circuit is controlled by a variable current source. The distributed amplifier may be an open collector distributed amplifier.

Variable gain optical modulator with open collector driver amplifier and method of operation

An amplifier system with high gain, compact size, and extended bandwidth is disclosed. The amplifier system includes one or more inputs configured to receive one or more input signals and a pre-driver configured to receive the one or more input signals. The pre-driver may comprise source connected FETs which create a virtual ground and may include inductors which cancel or counter parasitic capacitance of the FETs. The pre-driver amplifies the one or more input signals to create one or more pre-amplified signals, which are provided to a voltage divider network configured to reduce a DC bias voltage of the one or more pre-amplified signals, while maintaining a wide bandwidth range. An amplifier receives and amplifies the output of the voltage divider network to create amplified signals. The amplifier may comprise mirrored FET pairs in a common source configuration and a common gate arrangement.

Voltage controlled attenuator

A dc coupled amplifier includes a pre-driver, and amplifier and a bias control circuit. The pre-driver is configured to receive one or more input signals and amplify the one or more input signals to create one or more pre-amplified signals. The amplifier has cascode configured transistors configured to receive and amplify the one or more pre-amplified signals to create one or more amplified signals, the amplifier further having an output driver termination element. The bias control circuit is connected between the pre-driver and the amplifier, the bias control circuit receiving at least one bias current from the output driver termination element of the amplifier, wherein the pre-driver, the amplifier and the bias control circuit are all formed on a same die.

DC coupled amplifier having pre-driver and bias control

Compact high gain amplifier with DC coupled stages

Active bias circuits for integrated devices are described. In one example, an active bias circuit includes a voltage control element to establish a control voltage, an active bias device to provide a power bias responsive to the control voltage, and a compensation circuit connected to the active bias device. The compensation circuit can be configured to set output impedance and compensate for parasitic capacitance of the active bias device. In another embodiment, the voltage control element can be omitted, and a control voltage can be relied upon to directly control the power bias output provided by the active bias device. The active bias circuit can be used to power a driver of an integrated optical transmitter, in one example, among other possible applications.

Active bias circuit

In one embodiment, an amplification device has a temperature differential sensing circuit that reduces a local thermal memory effect. The amplification device may include an amplification circuit and biasing circuitry. The amplification device is operable to receive an input signal and generate and amplified output signal. The biasing circuitry generates a biasing signal that sets the quiescent operating level of the amplified output signal. The temperature differential sensing circuit provides a bias level adjustment signal that adjusts the biasing signal to maintain the quiescent operating level of the amplified output signal at a desired level.

Amplification device having compensation for a local thermal memory effect

An apparatus having an input transmission line, a plurality of amplifiers and an output transmission line is disclosed. The input transmission line may include a plurality of first inductors configured to receive an input voltage. The amplifiers may be configured to generate a plurality of intermediate currents by amplifying a plurality of intermediate voltages at a plurality of first nodes between the first inductors. The output transmission line generally includes a plurality of second inductors configured to generate an output current at an output node by combining the intermediate currents. Each of a plurality of second nodes connected to the second inductors may transfer a plurality of the intermediate currents. Each of the second inductors generally has a different one of a plurality of inductance values.

Distributed transconductance amplifier

An efficient power amplifier circuitry for a mobile terminal or similar wireless communication device is provided. The power amplifier circuitry includes an output stage configured as a collector controlled Doherty amplifier, wherein the collector controlled Doherty amplifier increases the efficiency of the power amplifier at backoff power levels. The output stage includes main and peaking amplifiers connected in parallel and operating 90 degrees out-of-phase. The main amplifier is controlled using a first variable supply voltage, and the peaking amplifier is controlled using a second variable supply voltage. The first and second variable supply voltages are provided such that the main amplifier is active and the peaking amplifier is inactive for output power levels less than a predetermined backoff from a maximum output power level, and both the main amplifier and peaking amplifiers are active and operating in concert for output power levels greater than the predetermined backoff.

Doherty amplifier configuration for a collector controlled power amplifier

A monolithic microwave integrated circuit (MMIC) semiconductor chip, for use with a hybrid coupler, in a frequency downconverter. The chip has a first input lead for receiving a first combined input signal from the coupler, a second input lead for receiving a second combined input signal from the coupler, and an output lead. Each input signal is a microwave signal combined with a further frequency signal, and one of the microwave and further frequency signals of the first combined signal is out of phase with one of the microwave and further frequency signals of the second combined signal. A single balanced mixer has a first single ended mixer for converting the first combined signal to a first intermediate frequency signal and a second single ended mixer for converting the second combined signal to a second intermediate frequency signal. An amplifier is coupled to the first and second mixers for forming an amplified unbalanced intermediate frequency (IF) signal at the output lead representative of the first and second intermediate frequency signals.

Single balanced frequency downconverter for direct broadcast satellite

A high efficiency multiple power level amplifier circuit for reducing power consumption during low power operations. A plurality of power amplifier stages are cascaded to provide multiple levels of amplification. At least one power amplification stage includes a signal switching network to allow one or any combination of power amplifiers to be switched out when lower power operations are desired. The switched out power amplifiers are biased such that substantially no current is drawn from the power source.

High efficiency multiple power level amplifier circuit

A monolithic microwave integrated circuit (MMIC) downconverter for a direct broadcast satellite low noise block downconverter is comprised of a mixer that produces sum and difference frequency signals from an oscillator signal and a radio frequency (RF) signal. An intermediate frequency (IF) signal is obtained by selecting the difference signal of the sum and difference frequency signals using a low pass filter. An active load and amplifier circuit coupled to the low pass filter both provides a DC bias voltage to the mixer that is substantially insensitive to DC current and amplifies the IF signal from the low pass filter. The combined active load and amplifier circuit conserves DC power and reduces the MMiC circuit size, thus reducing the Gallium Arsenide area and therefore, the component cost.

MMIC downconverter for a direct broadcast satellite low noise block

A 2-18 gigahertz monolithic distributed amplifier using dual-gate gallium arsenide field effect transistors for maximum gain over the design bandwidth.

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Palo Alto, CA, United States of America

Wayne Kennan