An oscillator includes an input terminal, an oscillation circuit section configured to cause a resonator to resonate to output an oscillator signal, a digital input section to which a signal for controlling an oscillation frequency of the oscillation circuit section is input via the input terminal, and a first bias circuit section including a constant current source configured to supply a reference current to the digital input section.

The present invention discloses a gain-boosted n-path passive-mixer-first receiver. According to another aspect of the present disclosure, a gain-boosted n-path passive-mixer-first receiver is provided. The receiver includes a number n of switch-capacitor (sc) sets, a resistor, and a transconductance amplifier. The sc sets connect in parallel, and the sc sets have a first node and a second node. The resistor connects to the first node. The transconductance amplifier connects to the resistor and the second node.

According to another aspect of the present disclosure, a radio-frequency-to-baseband-function-reuse receiver with shared amplifiers for common-mode and differential-mode amplification is provided. The receiver includes two set networks connected in parallel. The set networks includes a first and a second input capacitors, a first and a second output capacitors, a first transconductance amplifier having an input terminal, a second transconductance amplifier having an input terminal, a first switch, and a second switch. The first and the second input capacitors connect to a first node. The first and the second output capacitors connect to a second node. The first transconductance amplifier connects between the first input capacitor and the first output capacitor. The second transconductance amplifier connects between the second input capacitor and the second output capacitor. The first switch connects between the input terminal of the first transconductance amplifier and the second node. The second switch connects between the input terminal of the second transconductance amplifier and the second node.

Methods, systems, and circuits for providing compensation for voltage variation are disclosed. A system includes: a voltage comparator configured to assert a control signal in response to detecting that one or more of power supply voltages droops below a threshold amount; a phase locked loop (PLL) configured to divide an output frequency for the PLL in response to the assertion of the control signal; a plurality of voltage sensors corresponding to the plurality of power supply voltages, the voltage sensors configured to output respective digital signals indicative of a voltage level of its corresponding power supply voltage; and a control circuit configured to control an oscillator frequency in the PLL during the open-loop mode responsive to the respective digital signals.

Methods, systems, and circuits for providing compensation for voltage variation are disclosed. A system includes: a voltage comparator configured to assert a control signal in response to detecting that one or more of power supply voltages droops below a threshold amount; a phase locked loop (PLL) configured to divide an output frequency for the PLL in response to the assertion of the control signal; a plurality of voltage sensors corresponding to the plurality of power supply voltages, the voltage sensors configured to output respective digital signals indicative of a voltage level of its corresponding power supply voltage; and a control circuit configured to control an oscillator frequency in the PLL during the open-loop mode responsive to the respective digital signals.