A dynamic amplifier with a bypass design. An input pair of transistors receives a pair of differential inputs Vip and Vin and further provides first, second and third terminals. A load circuit provides a pair of differential outputs Vop and Von with the load circuit connected at a common mode terminal. In an amplification phase, a driver for amplification is coupled to the first terminal and the load circuit is coupled to the second and third terminals. A bypassing circuit is specifically provided. The bypassing circuit is coupled to the second and third terminals during a bypass period within the amplification phase.

A frequency-modulated continuous-wave radar system includes a waveform generator, a delta-sigma modulation circuit, a voltage controlled oscillator, a frequency divider circuit, a control circuit, an injection locked oscillator, a power amplifier circuit, a first power detection circuit, a second power detection circuit, a third power detection circuit, and a calibration engine circuit. The waveform generator, the delta-sigma modulation circuit, the voltage controlled oscillator, the frequency divider circuit, and the control circuit form a phase locked loop. The calibration engine circuit is coupled to the delta-sigma modulation circuit, the voltage controlled oscillator, the injection locked oscillator, the power amplifier circuit, the first power detection circuit, the second power detection circuit, and the third power detection circuit for adjusting frequency gains of the voltage controlled oscillator, the injection locked oscillator, and the power amplifier circuit to approach wideband flatness frequency responses.

An oscillating circuit has an injection-locked oscillator (ILO) and a calibration circuit. The ILO has a Gm cell and an LC tank. A first node of the Gm cell receives a first injection signal, and a second node of the Gm cell receives a second injection signal. The first injection signal and the second injection signal are differential signals. The Gm cell provides a negative resistance between a first output end and a second output end of the Gm cell. When the calibration circuit tunes a resonant frequency of the LC tank of the ILO, the magnitude of the negative resistance is reduced to control the ILO to stop self-oscillating. After finishing tuning the resonant frequency of the LC tank, the calibration circuit controls the ILO to start self-oscillating by increasing the magnitude of the negative resistance.

A method for enhancing linearity of the receiver front-end system includes receiving a radio frequency signal by an antenna, converting the radio frequency signal to first differential signals by a transformer module, adjusting frequencies of the first differential signals to generate second differential signals by a mixer module, detecting a common signal in order to reduce a common error of the second differential signals, and generating third differential signals according to a reference signal after the common error is reduced from the second differential signals. The first differential signals, the second differential signals, and the third differential signals are unbalanced.

A low voltage inverter-based amplifier includes a first inverter-based amplification module, a second inverter-based amplification module, an inverter-based feedforward module, and an inverter-based common mode detector. The first inverter-based amplification module receives an input signal. The second inverter-based amplification module receives the input signal through the inverter-based feedforward module, and receives a first output signal from the first inverter-based amplification module. The inverter-based common mode detector receives an amplified signal from the second inverter-based amplification module, and outputs a feedback signal to the second inverter-based amplification module. Since the first and the second inverter-based amplification modules are both inverter-based, the supply voltage of the low voltage inverter-based amplifier is provided to supply one PMOS and one NMOS for normal operation. Therefore, a number of cascade MOSs of the low voltage inverter-based amplifier is two, and the low voltage inverter-based amplifier can be normally operated under the low supply voltage.

A divider-less phase locked loop (PLL) includes a phase frequency detector (PFD), a charge pump (CP), a voltage controlled oscillator (VCO), a delay unit, and a clock gating unit. The PFD is electrically connected to the VCO through the CP, and the CP outputs a voltage control signal to the VCO. The VCO generates an output signal. The delay unit receives and delays a reference signal to generate a delay signal. The clock gating unit samples the output signal according to the delay signal. Since the clock gating unit samples the output signal according to the delay signal, the divider-less PLL does not need to include a divider to divide a frequency of the output signal. Therefore, power consumption of the divider-less PLL can be reduced.

A divider-less phase locked loop (PLL) includes a phase frequency detector (PFD), a charge pump (CP), a voltage controlled oscillator (VCO), a delay unit, and a clock gating unit. The PFD is electrically connected to the VCO through the CP, and the CP outputs a voltage control signal to the VCO. The VCO generates an output signal. The delay unit receives and delays a reference signal to generate a delay signal. The clock gating unit samples the output signal according to the delay signal. Since the clock gating unit samples the output signal according to the delay signal, the divider-less PLL does not need to include a divider to divide a frequency of the output signal. Therefore, power consumption of the divider-less PLL can be reduced.

A single-stage differential operational amplifier including an input stage formed by a pair of input transistors having control terminals connected to a respective first and second input, first conduction terminals coupled to a respective first and second output and second conduction terminals coupled to receive a polarization current. An output stage is formed by a pair of output transistors in diode configuration and having control terminals coupled to a relative first conduction terminal and connected to a respective first and second output, and second conduction terminals connected to a reference line. A coupling stage is interposed between the first conduction terminals of the output transistors and the first and second outputs to define the diode configuration of the output transistors and a gain value of the operational amplifier.

A line receiver comprising a switched capacitor circuit and a buffer is described. The buffer may be configured to receive, through the switched capacitor circuit, an analog signal. In response, the buffer may provide an output signal to a load, such as an analog-to-digital converter. The switched capacitor circuit may be controlled by a control circuitry, and may charge at least one capacitive element to a desired reference voltage. The reference voltage may be selected so as to bias the buffer with a desired DC current, and consequently, to provide a desired degree if linearity. The line receiver may further comprise a bias circuit configured to generate the reference voltage needed to bias the buffer with the desired DC current.

Embodiments disclosed herein relate to a bias circuit that uses Schottky diodes. Typically, a bias circuit will include a number of transistors used to generate a bias voltage or a bias current for a power amplifier. Many wireless devices include power amplifiers to facilitate processing signals for transmission and/or received signals. By substituting the bias circuit design with a design that utilizes Schottky diodes, the required battery voltage of the bias circuit may be reduced enabling the use of lower voltage power supplies.