Lansus Technologies Inc

Zhenjuan Cheng

Hua Long

Qian Zhao

Liyang Zhang

Dongjie Tang

A multi-mode multi-band power amplifier includes a controller, a wide-band amplifier channel and a fundamental impedance transformer. The controller receives an external signal and outputs a control signal according to the external signal. The wide-band amplifier channel receives single-band or multi-band RF signals through the input terminal, performs power amplification on the RF signals and outputs the RF signals through the output terminal. The fundamental impedance transformer includes a first segment shared by RF signals in all bands, second segments respectively special for RF signals in all bands, and a switching circuit controlled by the controller to separate RF signals subject to power amplification to the second segment in a switchable manner for multiplexed outputs.

Multi-mode multi-frequency power amplifier

A power amplifier gain attenuation circuit includes: a gain attenuation (reduction) circuit configured to receive an input signal, an external drive signal and a bias voltage, and output a secondary input signal after attenuating the input signal depending on the drive signal and bias voltage; an amplifier including: a bias input terminal configured to receive a bias voltage; a signal input terminal configured to receive a secondary input signal, and an output terminal configured to output a gained output signal. The power amplifier gain attenuation circuit can reduce a gain effectively, and the amount of phase jump caused by the attenuation is quite small.

Power amplifier and gain reduction circuit thereof

A power amplifier output power control circuit includes a first operational amplifier with a negative input terminal configured to receive a power control signal; a first PMOS transistor with a grid electrode connected to an output terminal of the first operational amplifier, a source electrode connected to an external power source, and a drain electrode grounded via a voltage dividing network; a power amplifier with a power end connected to the drain electrode of the first PMOS transistor, an input terminal configured to access to a signal to be amplified, and an output terminal configured to amplify the signal; and a current sampling circuit configured to produce sampling current after sampling current across the first PMOS transistor and providing a negative feedback signal for the positive input terminal of the first operational amplifier according to the sampling current such that total output power of the power amplifier keeps unchanged.

Power amplifier output power control circuit

A power amplifier gain switching circuit includes: a gain controller configured to receive an external input signal, output a first input signal, receive an external drive signal, and output a control signal based on the drive signal; an amplifier including: a bias input terminal configured to receive an external bias voltage; a signal input terminal configured to receive the first input signal; a control terminal configured to receive the control signal; and an output terminal configured to output an output signal with a gain; wherein the amplifier is configured to switch a gain factor of the output signal based on the control signal.

Power amplifier and gain switching circuit thereof

A multi-mode multi-band power amplifier and its circuits are provided. The power amplifier comprises a controller, a wide-band amplifier channel, and a fundamental impedance transformer. The controller receives an external signal and outputs a control signal according to the external signal. The wide-band amplifier channel receives a single-band or a multi-band RF signals through the input terminal, performs power amplification on the RF signals and outputs the RF signals through the output terminal. The fundamental impedance transformer comprises a first segment shared by RF signals in all bands, second segments respectively specific to RF signals in all bands, and a switching circuit controlled by the controller to separate a RF signal which is subject to power amplification to the second segment in a switchable manner for multiplexed outputs. A power amplifier output power control circuit, a gain switching circuit, and a gain attenuation circuit are also provided.

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Shenzhen, China

Zhenjuan Cheng