Abrégé

The invention relates to a switched mode power supply (102) arranged to provide a switched supply at one terminal of an inductor (106), another terminal of the inductor (106) being connected to a first input of an error amplifier (104) having a reference signal (VREF) at a second input, the error amplifier (104) generating a corrected switched supply at an output in dependence on the difference between signals at its first and second inputs, there being provided a feedback path (200) between the output of the error amplifier (104) and the first input of the error amplifier (104), and further comprising circuitry for sensing a switcher interference current in the feedback path (200) of the error amplifier (104), and for adjusting the corrected switched supply output to reduce the switcher interference current in the output.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie

Abrégé

There is disclosed a method of characterising an envelope tracking amplification stage comprising an amplifier for amplifying an input signal and an envelope tracking modulated power supply for generating a modulated supply voltage for the amplifier in dependence on the input signal envelope, and in which the input signal envelope to the envelope tracking modulated supply voltage is shaped by a shaping function, the method comprising: generating an input test waveform which is representative of an input waveform under normal operating conditions of the amplification stage; applying a respective one of a plurality of different shaping functions, each comprising a non-linear transfer function, to the input signal envelope in each of a plurality of test periods during the period in which the input test waveform is applied as the input signal to generate the input to the envelope tracking modulated supply voltage; measuring parameters of the amplification stage during the period in which the input test waveform is applied in order to allow determination of the gain, phase and efficiency characteristics of the amplifier; and for each of the gain, phase and efficiency characteristics, generating a three dimensional plot of the characteristic with respect to input power and supply voltage applied to the amplifier.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03G 3/30 - Commande automatique dans des amplificateurs comportant des dispositifs semi-conducteurs

Abrégé

There is described a method of controlling an envelope tracking amplification stage comprising an amplifier for amplifying an input signal, an envelope tracking modulated power supply for generating a modulated supply voltage for the amplifier in dependence on the input signal envelope, and in which the input signal envelope to the envelope tracking modulated supply voltage is shaped by a shaping function, and a pre-distortion block for pre-distorting the input signal to the amplifier, the method comprising : in a characterisation mode of the amplifier under test conditions : measuring parameters of the amplification stage to determine at least two of gain, phase and efficiency characteristics for instantaneous values of input power and supply voltage of the amplifier; and for each of the at least two of gain, phase and efficiency characteristics, generating a three-dimensional plot representing the characteristic with respect to input power and supply voltage applied to the amplifier, and in a use mode of the amplifier under normal operating conditions : using at least one of the three-dimensional plots to determine a shaping function for the shaping table in dependence on a primary system objective associated with one or more of gain, phase or efficiency; and using the determined shaping function and at least one of the three dimensional plots to determine the pre-distortion coefficients for the pre-distortion block to meet a secondary system objective associated with at least one of gain, phase or efficiency.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03G 3/30 - Commande automatique dans des amplificateurs comportant des dispositifs semi-conducteurs

Abrégé

There is disclosed a method of controlling an input to an envelope modulated power supply of an envelope tracking amplification stage, comprising: generating an envelope signal representing the envelope of a signal to be amplified; applying a shaping function to the envelope signal to generate a shaped envelope signal, including: clipping the shaped envelope signal at high input envelope values; and providing the shaped envelope signal as an input signal to the envelope modulated power supply.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a method of controlling an envelope tracking amplification stage comprising an envelope modulated power supply, the method comprising: determining a shaping function to be applied to an envelope signal for controlling the envelope modulated power supply in dependence on a system linearity objective in a region of operation of the amplifier in which the output power of the amplifier is dependent upon the supply voltage; and determining a pre-distortion function to be applied to an input signal to be amplified in dependence on a further linearity objective of the system, in a region of operation of the amplifier in which the output of the amplifier is dependent upon the input power to the amplifier.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 1/32 - Modifications des amplificateurs pour réduire la distorsion non linéaire
• H04L 25/03 - Réseaux de mise en forme pour émetteur ou récepteur, p. ex. réseaux de mise en forme adaptatifs
• H04L 25/02 - Systèmes à bande de base Détails

Abrégé

Apparatus and methods for voltage converters are provided. In one embodiment, a voltage conversion system includes a bypass circuit and a voltage converter including an inductor and a plurality of switches configured to control a current through the inductor. The bypass circuit includes a first p-type field effect transistor (PFET), a second PFET, a first n-type field effect transistor (NFET), and a second NFET. The first and second NFET transistors and the first and second PFET transistors are electrically connected between a first end and a second end of the inductor such that a source of the first PFET transistor and a drain of the first NFET transistor are electrically connected to the first end of the inductor and such that a drain of the second PFET transistor and a source of the second NFET transistor are electrically connected to the second end of the inductor.

Classes IPC  ?

• G05F 1/56 - Régulation de la tension ou de l'intensité là où la variable effectivement régulée par le dispositif de réglage final est du type continu utilisant des dispositifs à semi-conducteurs en série avec la charge comme dispositifs de réglage final
• H03F 1/30 - Modifications des amplificateurs pour réduire l'influence des variations de la température ou de la tension d'alimentation

Abrégé

There is disclosed a supply feed network for an envelope tracking power amplifier arrangement comprising a power amplifier and a voltage modulator for providing a supply voltage to the power amplifier, the supply feed network comprising: a power distribution plane arranged to connect the supply voltage from the voltage modulator to the power amplifier.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a power amplifier arrangement comprising: first and second active devices for amplifying in-phase and anti-phase parts of an input signal; a first DC supply network connected between the output of the first active device and a modulated supply voltage; a second DC supply network connected between the output of the second active device and the same modulated supply voltage and an output combiner for combining the amplified in-phase and anti-phase parts of the input signal.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/26 - Amplificateurs push-pullDéphaseurs pour ceux-ci

Abrégé

There is disclosed an asynchronous switch mode power supply comprising: a subtractor for subtracting an output of the switch mode power supply from a reference signal; a filter for filtering the subtracted output; a quantiser for generating a plurality of quantiser outputs in dependence on the integrated subtracted output; and a power switch stage for connecting one of a plurality of supply voltages to the output of the switch mode power supply in dependence on the quantiser outputs.

Classes IPC  ?

• H03F 3/217 - Amplificateurs de puissance de classe DAmplificateurs à commutation
• H02M 3/156 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H02M 3/158 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation comprenant plusieurs dispositifs à semi-conducteurs comme dispositifs de commande finale pour une charge unique

Abrégé

There is disclosed an amplifier arrangement comprising a plurality of amplifiers (PA) each arranged to amplify one of a plurality of different input signals (114), the arrangement comprising an envelope tracking modulator (122) for generating a common power supply voltage for the power amplifiers (PA), and further comprising an envelope selector (120) adapted to receive a plurality of signals representing the envelopes of the plurality of input signals (114), and adapted to generate an output envelope signal representing the one of the plurality of envelopes having the highest level at a particular time instant as the input signal for the envelope tracking modulator (122).

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 1/32 - Modifications des amplificateurs pour réduire la distorsion non linéaire
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie
• H03F 3/68 - Combinaisons d'amplificateurs, p. ex. amplificateurs à plusieurs voies pour stéréophonie

Abrégé

A method of calibrating a polar amplification stage including a main signal path and a magnitude signal path, the method comprising: generating signals (108, 142) for the main signal path and the magnitude signal path for operating an amplifier (102) between a linear mode of operation and a saturated mode of operation; detecting (114) first and second peaks in a signal at the output of the amplifier (102) representing transitions between the linear and saturated modes of operation; and adjusting (124) the timing in one of the main signal path and the amplitude signal path in dependence on a relative difference between the size of the detected first and second peaks.

Classes IPC  ?

• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 1/32 - Modifications des amplificateurs pour réduire la distorsion non linéaire

Abrégé

The invention relates to an apparatus comprising: a baseband controller (228) arranged to receive a digital envelope signal (110), the baseband controller (228) comprising: a digital-to- analogue converter (212) for converting the digital envelope signal (110) into an analogue envelope signal (244); and a digital controller (230) for generating a digital control signal (234) for a switching stage in dependence on the digital envelope signal (110), a modulated supply stage (246) comprising: a switching stage (214) for receiving the digital control signal (234) and for selecting one of a plurality of supply voltages in dependence on the digital control signal (234); a combiner (220) for combining the selected supply voltage with an error signal (218), and for providing a power supply signal (148); and an error amplifier (216) for receiving the analogue envelope signal (244) and the output of the combiner (220) and for generating the error signal (218).

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/189 - Amplificateurs à haute fréquence, p. ex. amplificateurs radiofréquence
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie

Abrégé

The invention relates to a method of calibrating an envelope path and an input path of an amplification stage including an envelope tracking power supply, the method comprising: generating input signals having a known relationship for each of the input and envelope paths; and varying an amplitude and a delay of the signal in one of the envelope and input paths in order to reduce the variation in the power detected in a signal at the output of the amplification stage.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is provided an amplification stage comprising: an input scaling block (218, 220, 114) for scaling an input signal in dependence on an input scaling factor to generate a scaled version of the input signal; a power amplifier (118) for receiving the scaled version of the input signal and for generating an amplified version of said signal; an envelope detector (110) for generating a signal representing the envelope of the input signal; an envelope scaling block (234) for scaling the envelope signal in dependence on an envelope scaling factor to generate a scaled version of the envelope signal; a non- linear mapping block (108) for generating a voltage representative of the supply voltage in dependence on the scaled envelope signal; a modulator (116) for generating a power supply voltage for the amplifier in dependence on the voltage generated by the non- linear mapping block; and a power control block (107a, 107b) for maintaining a linear relationship between the envelope scaling factor and the input scaling factor.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie

Abrégé

There is provided an output stage comprising: a phase splitter for receiving an input signal and for generating first and second drive signals of opposite phase in dependence thereon; a DC offset signal generator for generating a DC offset signal; an adder for adding the DC offset signal to the first drive signal to provide a first modified drive signal; a subtractor for subtracting the DC offset signal from the second drive signal to provide a second modified drive signal; a first drive transistor associated with a first power supply voltage, for generating a first output signal in dependence on the first modified drive signal; a second drive transistor associated with a second power supply voltage, for generating a second output signal in dependence on the second modified drive signal; and a combiner for combining the first and second output signals to generate a phase combined output signal, wherein the DC offset signal is generated in order to equalise the power dissipated in the first and second transistors.

Classes IPC  ?

• H03F 3/26 - Amplificateurs push-pullDéphaseurs pour ceux-ci
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

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.

Classes IPC  ?

• H03F 3/20 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie

Abrégé

There is disclosed an envelope tracked power supply comprising a high bandwidth, low delay closed loop switch mode power supply stage comprising: a pulse width modulator for generating a width modulated pulse in dependence on an input signal and an output voltage of the switch mode power supply stage; a wideband transformer, having a winding of a first side connected to receive the modulated pulse, and a winding of a second side; and an output stage connected to the winding of the second side of the transformer, and for generating the output voltage in dependence on the modulated pulse induced in the winding of the second side.

Classes IPC  ?

• H02M 3/156 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation
• H02M 3/158 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation comprenant plusieurs dispositifs à semi-conducteurs comme dispositifs de commande finale pour une charge unique
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/217 - Amplificateurs de puissance de classe DAmplificateurs à commutation
• H02M 1/08 - Circuits spécialement adaptés à la production d'une tension de commande pour les dispositifs à semi-conducteurs incorporés dans des convertisseurs statiques

Abrégé

There is provided an integrated circuit comprising a main push-pull amplifier (108, 110) with balanced outputs and an additional push-pull amplifier (862, 863) with balanced outputs. Each of these balanced outputs is connected to an off -chip load (822) via respective bonding wires (818, 828, 830, 880) to provide a combined amplified signal to the load. The additional amplifier serves to compensate for crossover distortions generated by the main amplifier.

Classes IPC  ?

• H03F 3/195 - Amplificateurs à haute fréquence, p. ex. amplificateurs radiofréquence comportant uniquement des dispositifs à semi-conducteurs dans des circuits intégrés
• H03F 3/26 - Amplificateurs push-pullDéphaseurs pour ceux-ci
• H03F 3/30 - Amplificateurs push-pull à sortie uniqueDéphaseurs pour ceux-ci

Abrégé

There is provided an amplifier arrangement comprising a main push pull amplifier (100) connected to receive an input signal and generate an amplified version of the input signal and an additional amplifier (624) that is a scaled down version of the main push pull amplifier. The main push pull amplifier (100) and the additional amplifier (624) are coupled in parallel to receive an input signal (122) and generate an amplified output signal (114), wherein the amplifier arrangement comprises optionally a high-pass filter (622) between the overall amplifier input (122) and the input of the additional amplifier (624). In order to reduce crossover distortions generated by the main push pull amplifier, the additional amplifier is designed to amplify the input signal during crossover, thus the output signal always follows the input signal.

Classes IPC  ?

• H03F 3/30 - Amplificateurs push-pull à sortie uniqueDéphaseurs pour ceux-ci
• H03F 3/26 - Amplificateurs push-pullDéphaseurs pour ceux-ci

Abrégé

There is disclosed a method of generating a supply voltage (230) for a power amplifier (114) arranged to amplify an input signal (228), comprising: generating (104) a target supply voltage tracking the input signal (228); predistorting (400) the target supply voltage to compensate for effects on a supply voltage in the amplifier (114); and generating (102) the supply voltage for the amplifier (114) in dependence on the predistorted target supply voltage (414).

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/193 - Amplificateurs à haute fréquence, p. ex. amplificateurs radiofréquence comportant uniquement des dispositifs à semi-conducteurs comportant des dispositifs à effet de champ
• H03F 1/32 - Modifications des amplificateurs pour réduire la distorsion non linéaire
• H03F 1/56 - Modifications des impédances d'entrée ou de sortie, non prévues ailleurs
• H03F 3/24 - Amplificateurs de puissance, p. ex. amplificateurs de classe B, amplificateur de classe C d'étages transmetteurs de sortie

Abrégé

There is disclosed a switching stage comprising: a first switching path having at least one switching element for selectively connecting an input of the switching stage to an output of the switching stage; and a second switching path having at least one switching element for selectively connecting the input of the switching stage to the output of the switching stage, wherein the first and second switching paths are controlled such that a signal is selectively routed from the input of the switching stage to the output of the switching stage via the first and second switching paths in dependence on the current of the signal to be routed.

Classes IPC  ?

• H02M 3/158 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation comprenant plusieurs dispositifs à semi-conducteurs comme dispositifs de commande finale pour une charge unique
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a method, in an amplifier stage comprising an amplifier and a modulated supply, the amplifier being arranged to amplify an input signal and the modulated supply being arranged to generate a supply voltage for the amplifier by tracking an envelope of the signal to be amplified, the method comprising: comparing the relative timing of a signal representing the current drawn by the amplifier from the modulated supply and a signal representing the voltage generated at the output of the modulated supply; and in dependence upon a difference in the relative timing, adjusting the timing of either the input signal to be amplified or the generated supply voltage to reduce the difference in the relative timing.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed an arrangement comprising: a driver stage connected to receive an input signal and generate a drive signal; a transformer comprising: a first winding of a first side of the transformer, across which winding a voltage signal is developed in dependence on the drive signal; and a second winding of the first side of the transformer, coupled to the first winding, which exhibits across it a voltage signal related to the voltage across the first winding, by swingback; and a first controller for comparing the voltage exhibited in the second winding to a first threshold voltage, and for selecting a first or a second supply voltage for the arrangement in dependence on the comparison.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/68 - Combinaisons d'amplificateurs, p. ex. amplificateurs à plusieurs voies pour stéréophonie

Abrégé

There is disclosed a power supply stage, and a method of controlling such, comprising: a means for generating an intermediate supply signal in dependence on a reference signal representing a desired power supply; and a plurality of adjusting means, each adapted to generate an adjusted supply signal tracking the reference signal, in dependence on the generated intermediate supply signal and the reference signal.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/68 - Combinaisons d'amplificateurs, p. ex. amplificateurs à plusieurs voies pour stéréophonie

Abrégé

There is disclosed a power supply stage, and a corresponding method, comprising: a plurality of amplifiers for amplifying an input signal, each amplifier receiving a power supply voltage; a common selection means for selecting one of a plurality of power supply voltages in dependence on a reference signal representing a desired power supply voltage; and a plurality of adjusting means, corresponding to the plurality of amplifiers, adapted to generate an adjusted selected power supply voltage for a respective amplifier tracking the reference signal in dependence on the one selected power supply voltage and the reference signal.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H03F 3/60 - Amplificateurs dans lesquels les réseaux de couplage ont des constantes réparties, p. ex. comportant des résonateurs de guides d'ondes

Abrégé

There is described a buck-boost converter comprising: a voltage source; an inductor, wherein a first terminal of the inductor is switchably connected to the voltage source; and a plurality of capacitors switchably connected to a second terminal of the inductor, wherein a respective plurality of output voltages are formed across the plurality of capacitors, further comprising: an error determination means, for determining an error in each of the plurality of voltages, an inner control loop adapted to switchably connect one of the plurality of capacitors to the second terminal of the inductor in dependence on the determined errors; and an outer control loop adapted to control switching between buck mode and boost mode in dependence upon the determined errors.

Classes IPC  ?

• H02M 3/158 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation comprenant plusieurs dispositifs à semi-conducteurs comme dispositifs de commande finale pour une charge unique

Abrégé

There is disclosed a multi-stage amplifier comprising: a first amplifier stage; a second amplifier stage; a first voltage supply stage arranged to provide a supply voltage to the first amplifier in dependence on an average power of a signal to be amplified; and a second voltage supply stage arranged to provide a supply voltage to the second amplifier in dependence on an instantaneous power of a signal to be amplified.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a method for generating pre-emphasis coefficients for a pre-emphasis stage of a non-linear distorting device, the method comprising the steps of: capturing, for a given time period, samples of an input signal and samples of an output signal; determining the direction of an error between the captured samples; adjusting the input signal in a direction to reduce the error to generate an estimate of the pre-distorted input signal; generating updated pre-distortion coefficients in dependence on the estimate of the pre-distorted input signal and generated pre-distortion coefficients for one or more previous time periods.

Classes IPC  ?

• H03F 1/32 - Modifications des amplificateurs pour réduire la distorsion non linéaire

Abrégé

There is described a method of generating a power supply tracking a reference signal, comprising the steps of: filtering the reference signal; generating a first voltage in dependence on the filtered reference signal; generating a second voltage in dependence on the reference signal; and combining the first and second voltages to provide a power supply voltage.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a method of forming a printed circuit board including a plate for providing thermal conductivity from an upper surface of the printed circuit board to a lower surface of the printed circuit board, the method comprising the steps of: providing an opening in the printed circuit board extending from the upper surface to the lower surface; providing a raised portion on the plate having dimensions corresponding to the opening in the printed circuit board, the height of said raised portion being greater than the thickness of the printed circuit board; laminating the printed circuit board and the metal plate to form the raised portion of the plate in the opening of the printed circuit board; and compressing the laminated structure to form a structure in which the upper surface of the printed circuit board is coplanar with the surface of the raised portion of the metal plate.

Classes IPC  ?

• H05K 1/02 - Circuits imprimés Détails

Abrégé

There is disclosed a buck-boost converter comprising a voltage generation apparatus comprising: a voltage source (110); an inductor (108), wherein a first terminal of the inductor is switchably connected to the voltage source; and a plurality of capacitors (202) switchably connected to a second terminal (116) of the inductor, wherein a respective plurality of voltages (Vi) are formed across the plurality of capacitors.

Classes IPC  ?

• H02M 3/158 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu sans transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs avec commande automatique de la tension ou du courant de sortie, p. ex. régulateurs à commutation comprenant plusieurs dispositifs à semi-conducteurs comme dispositifs de commande finale pour une charge unique

Abrégé

There is disclosed a voltage supply stage comprising: a selection means for selecting one of a plurality of power supply voltages in dependance on a reference signal representing a desired power supply voltage; a combining means for combining the selected power supply voltage with a correction signal to generate an adjusted power supply voltage; and an adjusting means adapted to generate the correction signal in dependence on the reference signal and the adjusted power supply voltage, wherein the selection means is arranged to select the one of the plurality of supply voltages further in dependence on a signal derived from one of the inputs to the combining means.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

There is disclosed a method and apparatus for generating, in an envelope tracking modulator of a mobile radio transmission apparatus, a pulse width modulated, PWM, signal representing a time-varying signal, the method comprising, for each time cycle : a) generating a rising ramp from a first voltage level to a second voltage level; b) generating a falling ramp from the second voltage level to the first voltage level; c) detecting a rising slope of the time-varying signal crossing the falling ramp and responsive thereto if the PWM signal is at the first voltage level, transitioning the PWM signal to the second voltage signal; d) detecting a falling slope of the time-varying signal crossing the rising ramp, and responsive thereto if the PWM signal is at the second voltage level, transitioning the PWM signal to the first voltage signal. The step of detecting a rising slope of the time-varying signal crossing the falling ramp or detecting a falling slope of the time-varying signal crossing the rising ramp comprises: generating a first current representing the first voltage level; generating a second ramp representing the second voltage level; subtracting the one current from the other to provide a ramp control signal for controlling the step of generating the rising ramp or the falling ramp; generating a reference current representing the time-varying signal; subtracting either the first or second current from the reference current to provide a comparison signal; and comparing the comparison signal with the generated ramp signal.

Classes IPC  ?

• H03K 7/08 - Modulation de durée ou de largeur
• H03M 1/50 - Convertisseurs analogiques/numériques avec conversion intermédiaire en intervalle de temps
• H03K 7/10 - Modulation combinée, p. ex. modulation de vitesse et modulation d'amplitude

Abrégé

There is provided a filter for receiving a rectangular or stepped source voltage to be filtered and for providing an output voltage, the filter including means arranged to determine the output voltage in dependence on the frequency components of the source voltage within the filter passband, and independent of output current drawn.

Classes IPC  ?

• H03F 3/217 - Amplificateurs de puissance de classe DAmplificateurs à commutation
• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

In accordance with the invention there is also provided a voltage combiner (200) comprising: a transformer (104) having a first (108) and second (110) winding each having a first and second tap; and an inductor (120) connected between the first and second taps of the second winding, wherein: the first tap of the first winding is adapted for connection to a first voltage (114), the first tap of the second winding is adapted for connection to a second voltage (102), and the second tap of the second winding is adapted to provide an output being the first and second voltages combined, and further wherein: the inductor (120) is adapted to provide a bypass path for the current associated with the second voltage. (102)

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire
• H01F 38/00 - Adaptations de transformateurs ou d'inductances à des applications ou des fonctions spécifiques
• H02M 3/335 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant continu avec transformation intermédiaire en courant alternatif par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrodes de commande pour produire le courant alternatif intermédiaire utilisant des dispositifs du type triode ou transistor exigeant l'application continue d'un signal de commande utilisant uniquement des dispositifs à semi-conducteurs
• H02M 7/48 - Transformation d'une puissance d'entrée en courant continu en une puissance de sortie en courant alternatif sans possibilité de réversibilité par convertisseurs statiques utilisant des tubes à décharge avec électrode de commande ou des dispositifs à semi-conducteurs avec électrode de commande

Abrégé

There is disclosed a method and apparatus for generating an output signal comprising a replica of an input signal, comprising the steps of : generating a replica signal representing the low frequency content of the input signal; generating an error signal representing an error in the replica signal; combining the replica signal with the error signal to generate an output signal; and wherein the step of generating the error signal further includes the steps of : generating a delay signal being a delayed version of the input signal; and determining a difference between the output signal and the delay signal which difference is the error signal.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire

Abrégé

A radio frequency amplifier system is disclosed in which the amplifier bias supply and power supply voltages are instantaneously modulated with signals derived from the envelope voltage of the input signal. Separate non-linear mapping functions are used to derive the supply and bias voltages. The two mapping functions are optimised jointly to achieve particular system performance goals, such as optimum efficiency, constant gain, constant phase, or minimum spectral spreading. An optimisation of particular interest is that which achieves best RF amplifier power added efficiency subject to achieving constant amplifier gain. In this way the need for pre-distortion linearization may be reduced or eliminated.

Classes IPC  ?

• H03F 1/02 - Modifications des amplificateurs pour augmenter leur rendement, p. ex. étages classe A à pente glissante, utilisation d'une oscillation auxiliaire