Abstract: A supply modulator, a modulated power supply circuit, and associated control method are provided. The modulated power supply circuit includes the supply modulator and a DC-DC voltage converter, and the supply modulator includes a linear amplifier and a switching converter. The linear amplifier generates an AC component of a modulated voltage according to a regulated voltage and an envelope tracking signal. The supply voltage is converted to the regulated voltage by the DC-DC voltage converter, and the regulated voltage is greater than or less than the supply voltage. The switching converter includes a step-down circuit and a path selection circuit. The path selection circuit selects one of the supply voltage and the regulated voltage as a DC input voltage. The step-down circuit converts the DC input voltage to a DC component of the modulated voltage which is less than the DC input voltage.

Abstract: A circuit module includes a power amplifier, a switch, and a bypass capacitor. The power amplifier has a signal input node coupled to an input signal, a signal output node to generate an output signal, and a power input node coupled to a supply output signal of a supply modulator. The switch is coupled between the power input node of the power amplifier and the bypass capacitor. The bypass capacitor is an equivalently removable bypass capacitor coupled between the switch and a ground level.

Abstract: A supply modulator, a modulated power supply circuit, and associated control method are provided. The modulated power supply circuit includes the supply modulator and a DC-DC voltage converter, and the supply modulator includes a linear amplifier and a switching converter. The linear amplifier generates an AC component of a modulated voltage according to a regulated voltage and an envelope tracking signal. The supply voltage is converted to the regulated voltage by the DC-DC voltage converter, and the regulated voltage is greater than or less than the supply voltage. The switching converter includes a step-down circuit and a path selection circuit. The path selection circuit selects one of the supply voltage and the regulated voltage as a DC input voltage. The step-down circuit converts the DC input voltage to a DC component of the modulated voltage which is less than the DC input voltage.

Abstract: A circuit module includes a power amplifier, a switch, and a bypass capacitor. The power amplifier has a signal input node coupled to an input signal, a signal output node to generate an output signal, and a power input node coupled to a supply output signal of a supply modulator. The switch is coupled between the power input node of the power amplifier and the bypass capacitor. The bypass capacitor is an equivalently removable bypass capacitor coupled between the switch and a ground level.

Abstract: Techniques and examples pertaining to variation calibration for envelope tracking on chip are described. Envelope tracking (ET) statistics among multiple wireless-capable mobile devices (e.g., smartphones) may be collected in laboratory. Optimal ET parameters may be determined based on ET statistics. An ET setting file may be generated for ET factory calibration. In production lines, the ET setting file may be loaded into each mobile device for ET factory calibration.

Abstract: Techniques and examples pertaining to variation calibration for envelope tracking on chip are described. Envelope tracking (ET) statistics among multiple wireless-capable mobile devices (e.g., smartphones) may be collected in laboratory. Optimal ET parameters may be determined based on ET statistics. An ET setting file may be generated for ET factory calibration. In production lines, the ET setting file may be loaded into each mobile device for ET factory calibration.

Abstract: A radio frequency (RF) signal control module is provided. The RF signal control module includes a detection and control device detecting at least one radio coupling value in a transmission band according to a radio coupling signal and generating a control signal for controlling transmission power an RF signal to be transmitted according to the detected radio coupling value.

Abstract: Improved voltage controlled oscillator (VCO) circuits are disclosed. A symmetrical voltage controlled oscillator (VCO) system according to the embodiments of the present invention comprises a frequency tuning circuit containing one or more varactors for receiving a predetermined tuning signal and a frequency tuning bias signal for altering capacitances of the varactors, a modulation circuit coupled in parallel with the frequency tuning circuit containing one or more varactors for modulating one or more outputs, and a core circuit coupled in a parallel with the tuning circuit and the modulation circuit for providing an oscillation mechanism, wherein the core circuit has an inductance module coupled in a parallel fashion with the frequency tuning circuit and the modulation circuit, wherein circuit elements of the VCO system are symmetrically arranged for increasing oscillation efficiency thereof and the varactors are tuned to deliver the output at an output frequency.

Abstract: Improved voltage controlled oscillator (VCO) circuits are disclosed. A symmetrical voltage controlled oscillator (VCO) system according to the embodiments of the present invention comprises a frequency tuning circuit containing one or more varactors for receiving a predetermined tuning signal and a frequency tuning bias signal for altering capacitances of the varactors, a modulation circuit coupled in parallel with the frequency tuning circuit containing one or more varactors for modulating one or more outputs, and a core circuit coupled in a parallel with the tuning circuit and the modulation circuit for providing an oscillation mechanism, wherein the core circuit has an inductance module coupled in a parallel fashion with the frequency tuning circuit and the modulation circuit, wherein circuit elements of the VCO system are symmetrically arranged for increasing oscillation efficiency thereof and the varactors are tuned to deliver the output at an output frequency.