Abstract: Apparatus and methods of calibrating a power amplifier system to compensate for envelope amplitude misalignment are provided. In certain configurations, a method of calibrating a power amplifier system includes generating a supply voltage of a power amplifier using an envelope tracker based on shaping a scaled envelope signal using shaping data generated at a target gain compression, controlling a variable gain of a variable gain amplifier based on a gain control level signal, changing the variable gain by adjusting the gain control level signal using a calibration module, monitoring an output of the power amplifier to determine an amount of variable gain at which a detected gain compression of the power amplifier corresponds to the target gain compression of the shaping data, and calibrating the power amplifier system to compensate for envelope amplitude misalignment based on the determined amount of variable gain.

Abstract: Methods of calibrating a power amplifier system to compensate for envelope amplitude misalignment are provided. In certain configurations, a method of calibrating a power amplifier system includes amplifying a radio frequency signal from a transceiver using a power amplifier and generating a supply voltage of the power amplifier using an envelope tracker, including generating a scaled envelope signal based on a power control level signal and an envelope signal, and shaping the scaled envelope signal using a shaping table generated at a target gain compression. The method further includes changing a scaling of the scaled envelope signal using a calibration module, monitoring an output of the power amplifier to determine an amount of scaling of the scaled envelope signal at which a detected gain compression of the power amplifier corresponds to the target gain compression of the shaping table, and calibrating the power amplifier system based on the determination.

Abstract: Methods of calibrating a power amplifier system to compensate for envelope amplitude misalignment are provided. In certain configurations, a method of calibrating a power amplifier system includes amplifying a radio frequency signal from a transceiver using a power amplifier and generating a supply voltage of the power amplifier using an envelope tracker, including generating a scaled envelope signal based on a power control level signal and an envelope signal, and shaping the scaled envelope signal using a shaping table generated at a target gain compression. The method further includes changing a scaling of the scaled envelope signal using a calibration module, monitoring an output of the power amplifier to determine an amount of scaling of the scaled envelope signal at which a detected gain compression of the power amplifier corresponds to the target gain compression of the shaping table, and calibrating the power amplifier system based on the determination.

Abstract: Apparatus and methods for calibration of envelope trackers are provided. In one embodiment, a power amplifier system includes a VGA that amplifies an RF input signal to generate an amplified RF input signal, a power amplifier that amplifies the amplified RF input signal to generate an RF output signal, and an envelope tracker that generates a supply voltage for the power amplifier. The envelope tracker includes a scaling module that generates a scaled envelope signal based on a power control level (PCL) signal and an envelope signal that changes in relation to an envelope of the RF input signal. The envelope tracker further includes a calibration module that controls an amount of scaling of the scaled envelope signal based on calibration data to compensate for an envelope amplitude misalignment of the envelope tracker. The envelope tracker controls the voltage level of the supply voltage based on the scaled envelope signal.

Abstract: Apparatus and methods for calibration of envelope trackers are provided. In one embodiment, a power amplifier system includes a VGA that amplifies an RF input signal to generate an amplified RF input signal, a power amplifier that amplifies the amplified RF input signal to generate an RF output signal, and an envelope tracker that generates a supply voltage for the power amplifier. The envelope tracker includes a scaling module that generates a scaled envelope signal based on a power control level (PCL) signal and an envelope signal that changes in relation to an envelope of the RF input signal. The envelope tracker further includes a calibration module that controls an amount of scaling of the scaled envelope signal based on calibration data to compensate for an envelope amplitude misalignment of the envelope tracker. The envelope tracker controls the voltage level of the supply voltage based on the scaled envelope signal.

Abstract: Apparatus and methods for envelope tracking calibration are provided. In one embodiment, a power amplifier system includes a power amplifier, an envelope tracker that generates the power amplifier's supply voltage, a power detector, and a calibration module. The envelope tracker includes an envelope shaping table generated at a desired gain compression and a scaling module that scales an amplitude of an envelope signal. The power detector measures the power amplifier's output power, and the calibration module provides calibration data to the scaling module to change the scaling of the envelope signal's amplitude. The calibration module sets the calibration data to a first value corresponding to a supply voltage level associated with substantially no gain compression, and reduces the supply voltage level by changing the calibration data until the power detector indicates that the gain compression of the power amplifier is about equal to the desired gain compression.

Abstract: Apparatus and methods for envelope tracking calibration are provided. In one embodiment, a power amplifier system includes a power amplifier, an envelope tracker that generates the power amplifier's supply voltage, a power detector, and a calibration module. The envelope tracker includes an envelope shaping table generated at a desired gain compression and a scaling module that scales an amplitude of an envelope signal. The power detector measures the power amplifier's output power, and the calibration module provides calibration data to the scaling module to change the scaling of the envelope signal's amplitude. The calibration module sets the calibration data to a first value corresponding to a supply voltage level associated with substantially no gain compression, and reduces the supply voltage level by changing the calibration data until the power detector indicates that the gain compression of the power amplifier is about equal to the desired gain compression.

Abstract: Apparatus and methods for envelope tracking calibration are provided. In one embodiment, a method of calibrating an envelope tracker having an envelope shaping table generated at a desired gain compression of a power amplifier is provided. The method includes generating a supply voltage for the power amplifier using the envelope tracker, operating the supply voltage of the power amplifier at a first voltage level associated with substantially no gain compression of the power amplifier, and measuring an output power of the power amplifier at the first voltage level. The method further includes decreasing a voltage level of the supply voltage one or more times and measuring the output power at each voltage level, determining a second voltage level of the power amplifier associated with a gain compression equal to about that of the desired gain compression, and calibrating the envelope tracker based on the determination.

Abstract: Apparatus and methods for envelope tracking calibration are provided. In one embodiment, a method of calibrating an envelope tracker having an envelope shaping table generated at a desired gain compression of a power amplifier is provided. The method includes generating a supply voltage for the power amplifier using the envelope tracker, operating the supply voltage of the power amplifier at a first voltage level associated with substantially no gain compression of the power amplifier, and measuring an output power of the power amplifier at the first voltage level. The method further includes decreasing a voltage level of the supply voltage one or more times and measuring the output power at each voltage level, determining a second voltage level of the power amplifier associated with a gain compression equal to about that of the desired gain compression, and calibrating the envelope tracker based on the determination.

Abstract: In a communication semiconductor integrated circuit device, an oscillator of a PLL circuit can operate in a plurality of frequency bands. With a control voltage (Vc) of the oscillator fixed to a predetermined value (VDC), an oscillation frequency of the oscillator is measured for each band to be stored in a storage. When the PLL operates, a setting value to specify a band is compared with the measured frequency values stored in the storage. As a result of the comparison, a band to be actually used by the oscillator is determined.

Abstract: In a polar loop based radio-communications apparatus having a phase control loop for controlling the phase of a carrier outputted from an oscillator for transmission, and an amplitude control loop for controlling the amplitude of a transmission output signal outputted from a power amplification circuit, the phase control loop is first started while maintaining the amplitude control loop in an off state at the outset of transmission, and the amplitude control loop is started after stabilizing the phase control loop.

Abstract: A transmitter adopting a polar loop system including a phase control loop for controlling the phase of a carrier signal outputted from a transmitting oscillator and an amplitude control loop for controlling the amplitude of a transmitting output signal outputted from a power amplification circuit, and designed to be capable of performing transmission using a GMSK modulation mode and transmission using an 8-PSK modulation mode. In the transmitter, the phase control loop is shared as a phase control loop for use in the GMSK modulation mode and a phase control loop for use in the 8-PSK modulation mode. A component similar to any one of components constituting a loop filter is provided in parallel therewith so that the component can be connected or disconnected in accordance with the modulation mode, for example, by use of a switching element.

Abstract: In one embodiment, a PLL circuit is provided with a plurality of pull-in operation modes for pulling a voltage across a filter capacitor (C1, C2) in a lock-up voltage, and with a register (CRG) for designating one of the plurality of pull-in operation modes. The pull-in operation is performed in accordance with a setting value in the register.

Abstract: A communication semiconductor integrated circuit has an oscillator circuit forming part of a transmission PLL circuit fabricated on a single semiconductor chip together with an oscillator circuit forming part of a reception PLL circuit and an oscillator circuit for an intermediate frequency. The oscillator circuit forming part of the transmission PLL circuit is configured to be operable in a plurality of bands. A circuit for measuring the oscillating frequency of the oscillator circuit forming part of the transmission PLL circuit is also used for measuring the oscillating frequency of the oscillator circuit forming part of the reception PLL circuit or for measuring the oscillating frequency of the oscillator circuit for the intermediate frequency.

Abstract: A semiconductor integrated circuit device for communication is provided with a PLL circuit or the like formed therein, the PLL circuit which is capable of realizing the compensation of fluctuation due to temperature change, the inhibition of increase in the chip area and the ensurement of the performance margin, and which controls a VCO having multiple oscillation frequency bands. In the case where automatic calibration is performed by switching a switch to a side of a DC voltage source in the PLL circuit using a VCO having multiple oscillation bands, a tuning voltage (Vtune) of an RFVCO is fixed to a voltage value of a DC voltage source. However, since a temperature characteristic of canceling a VCO oscillation frequency is given to the DC voltage source, it is possible to minimize the influence on the band selection when a calibration table comes to no optimum one.

Abstract: A semiconductor integrated circuit device for communication is provided with a PLL circuit or the like formed therein, the PLL circuit which is capable of realizing the compensation of fluctuation due to temperature change, the inhibition of increase in the chip area and the ensurement of the performance margin, and which controls a VCO having multiple oscillation frequency bands. In the case where automatic calibration is performed by switching a switch to a side of a DC voltage source in the PLL circuit using a VCO having multiple oscillation bands, a tuning voltage (Vtune) of an RFVCO is fixed to a voltage value of a DC voltage source. However, since a temperature characteristic of canceling a VCO oscillation frequency is given to the DC voltage source, it is possible to minimize the influence on the band selection when a calibration table comes to no optimum one.

Abstract: A transmitter adopting a polar loop system including a phase control loop for controlling the phase of a carrier signal outputted from a transmitting oscillator and an amplitude control loop for controlling the amplitude of a transmitting output signal outputted from a power amplification circuit, and designed to be capable of performing transmission using a GMSK modulation mode and transmission using an 8-PSK modulation mode. In the transmitter, the phase control loop is shared as a phase control loop for use in the GMSK modulation mode and a phase control loop for use in the 8-PSK modulation mode. A component similar to any one of components constituting a loop filter is provided in parallel therewith so that the component can be connected or disconnected in accordance with the modulation mode, for example, by use of a switching element.

Abstract: In a polar loop based radio-communications apparatus having a phase control loop for controlling the phase of a carrier outputted from an oscillator for transmission, and an amplitude control loop for controlling the amplitude of a transmission output signal outputted from a power amplification circuit, the phase control loop is first started while maintaining the amplitude control loop in an off state at the outset of transmission, and the amplitude control loop is started after stabilizing the phase control loop.

Abstract: In a communication semiconductor integrated circuit device, an oscillator (VCO 10) of a PLL circuit can operate in a plurality of frequency bands. With a control voltage (Vc) of the oscillator fixed to a predetermined value (VDC), an oscillation frequency of the oscillator is measured for each band to be stored in a storage (18). When the PLL operates, a setting value to specify a band is compared with the measured frequency values stored in the storage. As a result of the comparison, a band to be actually used by the oscillator is determined.

Abstract: A transmitter is provided which includes a transmitting circuit that does not require a high-performance low noise VCO restricting cost reduction thereof and that can reduce the number of parts without requiring an RF filter. A direct conversion that does not require a transmission VCO is applied to the transmitting circuit. In order to achieve noise reduction in a receiving band, low-pass filters are provided a IQ input sections of a modulator that converts IQ signals into RF signals. In comparison with a conventional transmitter using offset PLL, an external VCO required in addition to an RF integrated circuit, a power amplifier, and a front end circuit is reduced. Even in current transistor performance, by using a filter having rapid waveform characteristics such as a SAW more inexpensive than the VCO, or the like, it is possible to provide a GSM/GSM 1800/GSM1900 triple band transmitter.