摘要:
A noise shaping arrangement for a phase locked loop includes a first order sigma-delta modulator arranged to provide a first-order quantized output and a feedback path output. A second order sigma-delta modulator is arranged to receive the feedback path output and provides a second order quantized output. A combination block combines the first and second order quantized outputs to provide a combined third order quantized output, which provides noise shaping with a frequency notch spectrum. In this way a new quantization noise shape of third order is provided, such that quantization phase noise may be lowered, the PLL loop bandwidth may be increased, modulation phase error may be reduced and PLL locking speed increased.
摘要:
The present disclosure relates to an RF power amplifier (PA) power supply that includes a series pass circuit coupled across a direct current (DC)-to-DC converter to receive a power supply input signal, such as provided from a battery, to provide a power supply output signal to at least a first RF PA based on an output setpoint. Control circuitry selects between a switching supply operating mode and a non-switching supply operating mode based on the output setpoint. During the switching supply operating mode, the DC-to-DC converter provides the power supply output signal and during the non-switching supply operating mode, the series pass circuit provides the power supply output signal.
摘要:
Embodiments disclosed in the detailed description relate to a pseudo-envelope follower power management system including a parallel amplifier and a switch mode power supply converter cooperatively coupled to generate a power supply voltage at a power supply output coupled to a linear RF power amplifier. The parallel amplifier output is in communication with the power amplifier supply output. The parallel amplifier governs operation of the switch mode power supply converter and regulates the power amplifier supply voltage base on a VRAMP signal. The parallel amplifier circuit includes an open loop high frequency compensation assist circuit that generates a high frequency ripple compensation current based on an estimate of the high frequency ripple currents contained in a ripple current of the power inductor. The high frequency ripple compensation current is injected into the parallel amplifier circuit output to cancel out high frequency ripple currents at the power amplifier supply output.
摘要:
A charge pump includes an input, an output, and a fixed voltage node; a first capacitor and at least a second capacitor; and a plurality of switches adapted to selectively couple the first capacitor and the at least the second capacitor to the input, the output, and the fixed voltage node. A switch controller is adapted to switch the plurality of switches in response to at least three phase signals to provide fixed gains. A phase generator is adapted to generate the at least three phase signals, wherein at least one of the at least three phase signals has a duty cycle that is different from at least one other of the at least three phase signals. The phase generator is also adapted to adjust the frequency of a clock signal used to generate the at least three phase signals so that a minimum switching frequency is provided.
摘要:
A charge pump includes an input, an output, and a fixed voltage node; a first capacitor and at least a second capacitor; and a plurality of switches adapted to selectively couple the first capacitor and the at least the second capacitor to the input, the output, and the fixed voltage node. A switch controller is adapted to switch the plurality of switches in response to at least three phase signals to provide fixed gains. A phase generator is adapted to generate the at least three phase signals, wherein at least one of the at least three phase signals has a duty cycle that is different from at least one other of the at least three phase signals. The phase generator is also adapted to adjust the frequency of a clock signal used to generate the at least three phase signals so that a minimum switching frequency is provided.
摘要:
Embodiments disclosed in the detailed description relate to a pseudo-envelope follower power management system including a parallel amplifier and a switch mode power supply converter cooperatively coupled to generate a power supply voltage at a power supply output coupled to a linear RF power amplifier. The parallel amplifier output is in communication with the power amplifier supply output. The parallel amplifier governs operation of the switch mode power supply converter and regulates the power amplifier supply voltage base on a VRAMP signal. The parallel amplifier circuit includes an open loop high frequency compensation assist circuit that generates a high frequency ripple compensation current based on an estimate of the high frequency ripple currents contained in a ripple current of the power inductor. The high frequency ripple compensation current is injected into the parallel amplifier circuit output to cancel out high frequency ripple currents at the power amplifier supply output.
摘要:
An envelope tracking power supply and transmitter control circuitry are disclosed. The transmitter control circuitry receives a first envelope power supply control signal and a second envelope power supply control signal. The envelope tracking power supply operates in one of a group of operating modes, which includes a first operating mode and a second operating mode. During both the first operating mode and the second operating mode, a first envelope power supply signal is provided to a driver stage based on the first envelope power supply control signal. During the first operating mode, a second envelope power supply signal is provided to a final stage based on the first envelope power supply control signal. However, during the second operating mode, the second envelope power supply signal is provided to the final stage based on the second envelope power supply control signal.
摘要:
A noise shaping arrangement for a phase locked loop includes a first order sigma-delta modulator (500) arranged to provide a first-order quantized output and a feedback path output (508). A second order sigma-delta modulator (520) is arranged to receive the feedback path output (508) and provides a second order quantized output. A combination block (530) combines the first and second order quantized outputs to provide a combined third order quantized output (540), which provides noise shaping with a frequency notch spectrum. In this way a new quantization noise shape of third order is provided, such that quantization phase noise may be lowered, the PLL loop bandwidth may be increased, modulation phase error may be reduced and PLL locking speed increased.
摘要:
An envelope tracking power supply and transmitter control circuitry are disclosed. The transmitter control circuitry receives a first envelope power supply control signal and a second envelope power supply control signal. The envelope tracking power supply operates in one of a group of operating modes, which includes a first operating mode and a second operating mode. During both the first operating mode and the second operating mode, a first envelope power supply signal is provided to a driver stage based on the first envelope power supply control signal. During the first operating mode, a second envelope power supply signal is provided to a final stage based on the first envelope power supply control signal. However, during the second operating mode, the second envelope power supply signal is provided to the final stage based on the second envelope power supply control signal.
摘要:
Embodiments of the present disclosure relate to a multi-mode RF system, which is capable of transmitting and receiving RF signals using any of multiple RF communications bands. The multi-mode RF system may integrate RF band specific bandpass filters and low noise amplifiers (LNAs) into a single front-end module, such that each filter and amplifier pair provide selection and gain for at least one RF communications band. Outputs of the LNAs may be combined to provide one or more common signals to a transceiver module, which processes baseband signals associated with the RF communications bands. By integrating the filters and amplifiers into a single module, the filters and amplifiers may be closely coupled to one another, thereby supporting short signal paths between the filters and amplifiers, and having impedances high enough to provide good filter selectivity.