Qualcomm Incorporated

Janakiram Ganesh Sankaranarayanan

Bhushan Shanti Asuri

Ojas Choksi

Vinod Panikkath

Lai Kan Leung

Timothy Donald Gathman

Himanshu Khatri

Hongyan Yan

Jun Tan

Mehmet Ipek

Hasnain Lakdawala

Faramarz Sabouri

Wei Zhuo

Maulin Pareshbhai Bhagat

Haigang Feng

Maulin Bhagat

Vinod V Panikkath

An amplifying circuit includes a first reconfigurable amplifier configured to selectively operate in a cascode mode or a non-cascode mode, wherein an input of the first reconfigurable amplifier is coupled to a first input of the amplifying circuit, and an output of the first reconfigurable amplifier is coupled to an output of the amplifying circuit. The amplifying circuit also includes a second reconfigurable amplifier configured to selectively operate in the cascode mode or the non-cascode mode, wherein an input of the second reconfigurable amplifier is coupled to a second input of the amplifying circuit, and an output of the second reconfigurable amplifier is coupled to the output of the amplifying circuit.

Reconfigurable amplifier

A reconfigurable amplifier includes a first transistor having a gate coupled to an input of the reconfigurable amplifier, and a source coupled to a ground. The reconfigurable amplifier also includes a gate control circuit, and a second transistor having a gate coupled to the gate control circuit, a source coupled to a drain of the first transistor, and a drain coupled to an output of the reconfigurable amplifier, wherein the gate control circuit is configured to output a bias voltage to the gate of the second transistor in a cascode mode, and output a switch voltage to the gate of the second transistor in a non-cascode mode. The reconfigurable amplifier further includes a load coupled to the output of the reconfigurable amplifier.

An apparatus including: at least one receiver having injection points and having at least an amplifier and a transformer; and a plurality of isolation switches coupled to injection points of the at least one receiver, the plurality of isolation switches configured to route a calibration signal generated by a transmitter to one of the injection points.

On-chip linearity calibration

A device includes a main low noise amplifier (LNA) stage configured to amplify a single-ended communication signal, an auxiliary LNA stage coupled to the main LNA stage, the auxiliary LNA stage configured to cancel non-linear second order products generated by the main LNA stage, and a load circuit configured to receive an output of the main LNA stage and an output of the auxiliary LNA stage, the load circuit configured to convert the single-ended communication signal to a differential signal.

Distortion cancellation for low noise amplifier (LNA) non-linear second order products

A tunable wide band driver amplifier is disclosed. In an exemplary embodiment, an apparatus includes a first band selection circuit selectively connected between an output terminal of an amplifier and a circuit ground. The first band selection circuit configured to adjust an amplification band from a first frequency band to a second frequency band. The apparatus also includes a first harmonic reduction circuit selectively connected between the first band selection circuit and the circuit ground and configured to reduce 2harmonic frequencies associated with the first frequency band when the amplification band is set to the first frequency band.

Tunable wide band driver amplifier

Disclosed are circuits, techniques and methods for implementing an attenuator in a signal transmission path. In one particular implementation, an attenuation may be adjusted based, at least in part, on a control signal. In another implementation, such an attenuation may be adjusted in coarse increments by varying one or more gate voltages applied one or more transistors. In yet another implementation, adjusting said attenuation in fine increments by varying a bias voltage applied to at least one level shifter.

Programmable attenuator

In a first aspect, an RF switch includes a main transistor and a gate-to-source shorting circuit. When the RF switch is turned off, the gate-to-source shorting circuit is turned on to short the source and gate of the main transistor together, thereby preventing a Vgs from developing that would cause the main transistor to leak. When the RF switch is turned on, the gate-to-source shorting circuit is turned off to decouple the source from the gate. The gate is supplied with a digital logic high voltage to turn on the main transistor. In a second aspect, an RF switch includes a main transistor that has a bulk terminal. When the RF switch is turned off, the bulk is connected to ground through a high resistance. When the RF switch is turned on, the source and bulk are shorted together thereby reducing the threshold voltage of the main transistor.

RF isolation switch circuit

An RF transmitter capable of transmitting over a wide range of frequencies includes a mixer, a wideband high-Q balun, a first driver amplifier and a second driver amplifier. The balun has a single primary winding and two secondary windings. A differential output of the mixer is coupled to the primary winding. A first of the two secondary windings is coupled to drive the first driver amplifier. A second of the two secondary windings is coupled to drive the second driver amplifier. One driver amplifier is used when transmitting at lower frequencies whereas the other driver amplifier is used when transmitting at higher frequencies. By appropriate sizing of the inductances of the secondary windings and by switching out one of the secondary windings at certain times, the balun is tunable to operate over the wide frequency range while having a high quality factor Q, thereby facilitating reduced power consumption while simultaneously meeting performance requirements.

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San Diego, CA, United States of America

Janakiram Ganesh Sankaranarayanan