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.

Disclosed include methods and devices for enabling a battery free Bluetooth low energy communication. Some embodiments include a transmitter and a reference voltage generator supplying a voltage to an oscillator circuit. Further, some embodiments include an oscillator circuit including two pairs of semiconductor devices, wherein each pair of a semiconductor device includes a device with a gate node coupled to an antenna positive node interface (Vop) via a capacitor and a drain connected to an antenna negative node interface (Von) and a device with a gate node coupled to an antenna positive node interface (Von) via a capacitor and a drain connected to an antenna negative node interface (Vop). Additionally, some embodiments include an oscillator circuit connected to a common mode feedback circuit.

An amplifier circuit with novel design is provided. The amplifier circuit includes an input stage, a resistor, an output stage, an intermediate stage and a gm circuit. The input stage is coupled to a first supply voltage, and is arranged to receive an input voltage and a feedback current. The resistor is coupled between the input voltage and the input stage. The output stage is coupled to a second supply voltage, and is arranged to provide an output voltage for driving a load. The intermediate stage is coupled between the input stage and the output stage, and includes a level shifter. The gm circuit is coupled to the input stage, and is arranged to compare the input voltage with a common mode voltage, and thereby generates a compensate current for the input stage.

An amplifier circuit with novel design is provided. The amplifier circuit includes an input stage, a resistor, an output stage, an intermediate stage and a gm circuit. The input stage is coupled to a first supply voltage, and is arranged to receive an input voltage and a feedback current. The resistor is coupled between the input voltage and the input stage. The output stage is coupled to a second supply voltage, and is arranged to provide an output voltage for driving a load. The intermediate stage is coupled between the input stage and the output stage, and includes a level shifter. The gm circuit is coupled to the input stage, and is arranged to compare the input voltage with a common mode voltage, and thereby generates a compensate current for the input stage.

Disclosed include methods and devices for enabling a battery free Bluetooth low energy communication. Some embodiments include a transmitter and a reference voltage generator supplying a voltage to an oscillator circuit. Further, some embodiments include an oscillator circuit including two pairs of semiconductor devices, wherein each pair of a semiconductor device includes a device with a gate node coupled to an antenna positive node interface (Vop) via a capacitor and a drain connected to an antenna negative node interface (Von) and a device with a gate node coupled to an antenna positive node interface (Von) via a capacitor and a drain connected to an antenna negative node interface (Vop). Additionally, some embodiments include an oscillator circuit connected to a common mode feedback circuit.

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.

Various embodiments of the present technology comprise a method and apparatus for an operational amplifier with a variable gain-bandwidth product. According to various embodiments, an amplifier circuit comprising the operational amplifier operates in multiple stages and provides a low gain-bandwidth and a high gain-bandwidth.

Various embodiments of the present technology may provide methods and apparatus for an amplifier integrated circuit. The amplifier integrated circuit may provide a low gain bandwidth product to amplify at a higher speed and a high gain bandwidth product to amplify at a lower speed. The amplifier integrated circuit may achieve the low and high gain bandwidth product by generating a first current and a second current through a plurality of sets of series-connected transistors and operating a plurality of switches.

Various embodiments of the present technology may comprise methods and apparatus for an amplifier circuit. Methods and apparatus for an amplifier circuit according to various aspects of the present invention may be utilized in a digital-to-analog converter. The amplifier circuit may comprise a first operational amplifier with a feedback circuit. The feedback circuit may comprise an inverting amplifier circuit.

This applications relates to methods and apparatus for amplifying signals from capacitive transducers, in particular MEMS transducers such as MEMS capacitive microphones. An amplifier circuit has a signal node for receiving the input signal, a transducer biasing node for outputting a transducer bias voltage for biasing the capacitive transducer, and a voltage buffer configured to generate a buffered bias voltage at a buffer node. An amplifier arrangement is configured to receive the input signal from the signal node and the buffered bias voltage. The amplifier circuit comprises a signal path for supplying the buffered bias voltage to the transducer biasing node via a first capacitance, and the amplifier arrangement comprises a feedback resistor network configured such that: a change in input signal with respect to the buffered bias voltage results in a change in the output signal with respect to the buffered bias voltage with a gain greater than one; and a change in the buffered bias voltage results in a change in the output signal with a gain equal to one.