The present invention provides a class AB amplifier, wherein the class AB amplifier includes a cascode stage with a filter and an output stage. The cascode stage with the filter is arranged for receiving an input signal to generate a first driving signal and a second driving signal, wherein the filter filters the input signal to generate an filtered input signal, and at least one of the first driving signal and the second driving signal is generated according to the filtered input signal. The output stage is coupled to the cascode stage, and is arranged for generating an output signal according to the first driving signal and the second driving signal.

A multi-stage low-noise amplifier (LNA) device with a band pass response includes a first LNA in series with a second LNA. The device further includes multiple outputs coupled to the second LNA. Each of the outputs is capable of being active at the same time. The device further includes a high pass filter coupled between the first LNA and the second LNA.

A high-frequency module (1) includes a first substrate (101), a second substrate (102) that faces the first substrate (101), a support (103) that supports the first substrate (101) and the second substrate (102), and a plurality of high-frequency circuit components arranged in internal space formed by the first substrate (101), the second substrate (102), and the support and on both of facing principal faces of the first substrate (101) and the second substrate (102), and the plurality of high-frequency circuit components include a power amplifier element that constitutes a power amplifier circuit (16).

A device includes a substrate and a package input terminal. The device includes a driver amplifier mounted to the substrate and configured to receive a radio frequency input signal. A first amplifier is mounted to the substrate. The first amplifier includes a first amplifier input terminal. A second amplifier is mounted to the substrate. The second amplifier includes a second amplifier input terminal. An inter-stage network is connected between the driver amplifier and the first amplifier and between the driver amplifier and the second amplifier. The inter-stage network includes a first capacitor connected between the driver amplifier and the first amplifier input terminal, and an inductor having a first terminal and a second terminal. The first terminal of the inductor is connected to the first capacitor. The inter-stage network includes a second capacitor connected between the second terminal of the inductor and the second amplifier input terminal.

A wireless radio frequency transceiver system for Internet of Things includes: a wireless radio frequency transmission module and a wireless radio frequency receiving module. The wireless radio frequency transmission module is used to shape signal waveform of digital signals from the Internet of Things to modulate the digital signals to form modulated output signals, and adopt a self-mixing technique to increase voltage/current amplitude of the modulated output signals and reduce phase noise. The wireless radio frequency transmission module is further used to adopt a current reuse technique to amplify the voltage/current amplitude of the modulated output signals, and transmit the amplified modulated output signals through a first antenna to a wireless channel. The wireless radio frequency receiving module is used to detect carrier input signals received from a second antenna to obtain baseband signals and demodulate the baseband signals to form differential signals. The wireless radio frequency receiving module is further used to amplify voltage/current amplitude of the demodulated differential signals several times in an open loop state to produce digital output signals, and transmit the digital output signals to a back-end signal processor.

A cascoded high-voltage amplifier with Class D-H preamplifier is disclosed. The cascoded amplifier can include a chain of series-coupled low-voltage amplifiers, sometimes with a common gain, where an output of each low-voltage amplifier is coupled to an input of a next low-voltage amplifier, and inputs of adjacent low-voltage amplifiers are coupled via a feedforward connection, and optionally through an impedance component. In this way, a change in the input signal to the preamplifier can level shift the entire chain of low-voltage amplifiers through the feedforward connections. The gain of the cascoded high-voltage amplifier can be a function of the number of low-voltage amplifiers plus that of the Class D-H preamplifier, and a high-voltage output can be achieved without seeing high-voltage drops within the amplifier.

Circuits for low noise amplifiers with interferer reflecting loops are provided. In some embodiments, circuits for a low noise amplifier with an interferer reflecting loop are provided, the circuits comprising: a low noise amplifier (LNA) having an input and an output; a buffer having an input coupled to the output of the LNA and an output; and notch filter having an input coupled to the output of the buffer and an output coupled to the input of the LNA.

A sensor device of the present invention includes first sensors receiving a plurality of driving signals; second sensors outputting a plurality of sensing signals in response to the driving signals; and a sensor receiver connected receiving the sensing signals from the second sensors, and including a band pass filter filtering the sensing signals. The band pass filter includes a multi-path filter in which a frequency of the driving signals is set as a center frequency; a gain amplifier amplifying signals filtered through the multi-path filter according to a predetermined gain value; and a buffer isolating the multi-path filter and the gain amplifier from each other.

A method for pre-amplifying an input voltage signal to a pre-amplified voltage signal. The method includes receiving the input voltage signal; obtaining a high-pass filtered voltage signal by applying a high-pass filter to the input voltage signal; processing the high-pass filtered voltage signal to a current signal that corresponds to the high-pass filtered voltage signal; transmitting the current signal through a differential transmission line; converting the transmitted current signal to a converted voltage signal that corresponds to the high-pass filtered voltage signal; and outputting the converted voltage signal as the pre-amplified voltage signal. An integrated circuit chip implementing the method is also disclosed.

Low-noise amplifier having inter-stage filter. In some embodiments, an amplifier assembly for amplifying a signal can include an input amplification stage and an output amplification stage. The amplifier assembly can further include an inter-stage filter implemented between the input amplification stage and the output amplification stage.