Patents Assigned to RF Micro Devices, Inc.
  • Patent number: 9294041
    Abstract: This disclosure relates generally to radio frequency (RF) switching converters and RF amplification devices that use RF switching converters. For example, an RF switching converter may include a switching circuit that receives a power source voltage and a switching controller that receives a target average frequency value identifying a target average frequency. The switching circuit is switchable so as to generate a pulsed output voltage from the power source voltage. The switching controller switches the switching circuit such that the pulsed output voltage has an average pulse frequency. The switching controller also detects that the average pulse frequency of the pulsed output voltage during a time period differs from the target average frequency, and reduces a difference between the average pulse frequency and the target average frequency. In this manner, the effects of manufacturing variations and operational variations on the average pulse frequency can be eliminated, or at least diminished.
    Type: Grant
    Filed: October 26, 2012
    Date of Patent: March 22, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Nadim Khlat, Christopher Truong Ngo
  • Patent number: 9294045
    Abstract: Embodiments of a radio frequency (RF) amplification device having an RF amplification circuit and an amplifier control circuit operably associated with the RF amplification circuit are disclosed. The RF amplification circuit is configured to amplify an RF signal in accordance with a transfer function. The amplifier control circuit includes a closed-loop linearization circuit and a calibration circuit. The closed-loop linearization circuit is configured to be activated so that the transfer function defines a closed-loop response and inactive so that the transfer function defines an open-loop response. For example, the closed-loop linearization circuit may become inactive at small-signal power levels. Accordingly, the amplifier control circuit also includes a calibration circuit configured to reduce a difference between the open-loop response and the closed-loop response of the transfer function.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: March 22, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Baker Scott, George Maxim, Dirk Robert Walter Leipold
  • Patent number: 9294067
    Abstract: In one embodiment, a balanced to unbalanced transformer utilizes a crossover configuration such that some portion of the secondary coil (inductor) is shared between two resonators (capacitors). Adding a first capacitor in parallel with a portion of the secondary inductor creates a first harmonic trap (filter), and also efficiently uses the secondary coil (inductor) as a resonating element. Adding a second capacitor which shares (crossover configuration) a portion of the secondary inductor with the first capacitor creates a second harmonic trap (filter), which may be tuned to the same harmonic as the first harmonic trap, or may be tuned to a different harmonic.
    Type: Grant
    Filed: November 5, 2012
    Date of Patent: March 22, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Michael F. Zybura, Marcus Granger-Jones
  • Patent number: 9280163
    Abstract: This disclosure relates to radio frequency (RF) power converters and methods of operating the same. In one embodiment, an RF power converter includes an RF switching converter, a low-drop out (LDO) regulation circuit, and an RF filter. The RF filter is coupled to receive a pulsed output voltage from the RF switching converter and a supply voltage from the LDO regulation circuit. The RF filter is operable to alternate between a first RF filter topology and a second RF filter topology. In the first RF filter topology, the RF filter is configured to convert the pulsed output voltage from a switching circuit into the supply voltage. The RF filter in the second RF filter topology is configured to filter the supply voltage from the LDO regulation circuit to reduce a ripple variation in a supply voltage level of the supply voltage. As such, the RF filter provides greater versatility.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: March 8, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Michael R. Kay, Nadim Khlat
  • Patent number: 9281850
    Abstract: The present invention relates to an adaptable RF impedance translation circuit that includes a first group of inductive elements cascaded in series between an input and an output without any series switching elements, a second group of inductive elements cascaded in series, and a group of switching elements that are capable of electrically coupling the first group of inductive elements to the second group of inductive elements. Further, the adaptable RF impedance translation circuit includes at least one variable shunt capacitance circuit electrically coupled between a common reference and at least one connection node in the adaptable RF impedance translation circuit, which includes control circuitry to select either an OFF state or an ON state associated with each of the switching elements and to select a capacitance associated with each variable shunt capacitance circuit to control impedance translation characteristics of the adaptable RF impedance translation circuit.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: March 8, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Marcelo J. Franco, David C. Dening, Robert J. Baeten
  • Patent number: 9276784
    Abstract: A baseband PA predistortion module, which includes a baseband combiner, a baseband PA correction circuit, and a baseband filter, is disclosed. The baseband PA correction circuit replicates behavior of an RF PA by processing a modulation data signal to provide a predistortion data signal. The behavior of the RF PA includes distortion. The modulation data signal is representative of an RF input signal to an RF PA and the predistortion data signal is representative of a correction needed at an output of the RF PA. The baseband filter receives and filters the predistortion data signal to provide a reduced predistortion data signal, such that a low frequency content of the reduced predistortion data signal is less than a low frequency content of the predistortion data signal. The baseband combiner receives and combines the modulation data signal and the reduced predistortion data signal to provide a baseband transmit signal.
    Type: Grant
    Filed: November 19, 2014
    Date of Patent: March 1, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Andrew F. Folkmann, Nadim Khlat
  • Patent number: 9276552
    Abstract: A directional coupler that provides directional coupling and an impedance transformation is disclosed. In one embodiment, the directional coupler includes a low pass filter having a filter inductor that is coupled between an input port and an output port and a filter capacitor coupled between the output port and ground. The directional coupler also includes detector circuitry wherein the filter inductor is magnetically coupled to a detector inductor in the detector circuitry such that current passing through the filter inductor generates a detector current through the detector inductor. Furthermore, the low pass filter and the detector circuitry cooperate to transform a first impedance presented at the output port to a second impedance presented at the input port. Accordingly, the filter inductor is used in the low pass filter to provide an impedance transformation so as to operate with the detector circuitry to provide a detector current for directional coupling.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: March 1, 2016
    Assignee: RF Micro Devices, Inc.
    Inventor: David E. Jones
  • Patent number: 9270302
    Abstract: Front end circuitry includes at least three antenna nodes, a first duplexer, a second duplexer, a first diplexer, transceiver circuitry, and front end switching circuitry. The transceiver circuitry is coupled to the first duplexer, the second duplexer, and the first diplexer. The front end switching circuitry is coupled between the antenna nodes, the first duplexer, the second duplexer, and the first diplexer and configured to selectively couple the first duplexer to a first one of the antenna nodes, selectively couple the second duplexer to a second one of the antenna nodes, and selectively couple the first diplexer to a third one of the antenna nodes.
    Type: Grant
    Filed: June 12, 2014
    Date of Patent: February 23, 2016
    Assignee: RF Micro Devices, Inc.
    Inventor: Nadim Khlat
  • Patent number: 9263996
    Abstract: A method of defining a quasi iso-gain supply voltage function for an envelope tracking system is disclosed. The method includes a step of capturing iso-gain supply voltage values versus power values for a device under test (DUT). Other steps involve locating a minimum iso-gain supply voltage value, and then replacing the iso-gain supply voltage values with the minimum iso-gain supply voltage value for corresponding output power values that are less than an output power value corresponding to the minimum iso-gain supply voltage value. The method further includes a step of generating a look-up table (LUT) of iso-gain supply voltage values as a function of input power for the DUT after the step of replacing the iso-gain supply voltage values with the minimum iso-gain supply voltage value for corresponding output power values that are less than an output power value corresponding to the minimum iso-gain supply voltage value.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: February 16, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Andrew F. Folkmann, James M. Retz, Nadim Khlat, Jean-Frederic Chiron
  • Patent number: 9263991
    Abstract: In one embodiment, a digital internal amplified voltage of power management circuitry is forced to an input threshold voltage upon a determination that a set of emergency conditions is satisfied, and is set to an input minimum battery voltage upon a determination that the set of emergency conditions is not satisfied. The emergency conditions may include determining that a battery voltage is less than a threshold voltage and determining that an input minimum battery voltage is less than an input threshold voltage.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: February 16, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Nadim Khlat, Jean-Blaise Pierres, Michael R Kay
  • Patent number: 9256234
    Abstract: This disclosure relates to radio frequency (RF) power converters and methods of operating the same. In one embodiment, an RF power converter includes an RF switching converter, a low-drop out (LDO) regulation circuit, and an RF filter. The RF filter is coupled to receive a pulsed output voltage from the RF switching converter and a supply voltage from the LDO regulation circuit. The RF filter is operable to alternate between a first RF filter topology and a second RF filter topology. In the first RF filter topology, the RF filter is configured to convert the pulsed output voltage from a switching circuit into the supply voltage. The RF filter in the second RF filter topology is configured to filter the supply voltage from the LDO regulation circuit to reduce a ripple variation in a supply voltage level of the supply voltage. As such, the RF filter provides greater versatility.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: February 9, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Michael R. Kay, Nadim Khlat
  • Patent number: 9250643
    Abstract: Embodiments of circuitry, which includes power supply switching circuitry, a first inductive element, and a second inductive element, are disclosed. The power supply switching circuitry provides a first switching output signal to the first inductive element and a second switching output signal to the second inductive element. The first inductive element has a first inductor current and the second inductive element has a second inductor current. The second switching output signal is delayed from the first switching output signal by a switching signal delay. The first inductor current and the second inductor current combine to provide a combined inductor current, which has a frequency response with a group of notches, such that frequency locations of the group of notches are based on the switching signal delay.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: February 2, 2016
    Assignee: RF Micro Devices, Inc.
    Inventor: Nadim Khlat
  • Patent number: 9247496
    Abstract: Configuration-feedback circuitry and transceiver circuitry are disclosed. The configuration-feedback circuitry regulates an output power from a radio frequency power amplifier based on a difference between a target output power from the radio frequency power amplifier and a measured output power from the radio frequency power amplifier. The transceiver circuitry regulates a modulated power supply voltage, which is used by the radio frequency power amplifier to provide power for amplification, based on the difference between the target output power from the radio frequency power amplifier and the measured output power from the radio frequency power amplifier.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: January 26, 2016
    Assignee: RF Micro Devices, Inc.
    Inventor: Nadim Khlat
  • Patent number: 9246536
    Abstract: Embodiments disclosed herein relate to programmable duplexers. The frequency pass band of the programmable duplexer is changed according to a selection of a channel-pair to control or maximize the transition band between the receiver path and the transmitter path. The programmable duplexer permits selections of desired pass bands without the need for multiple duplexer filters. Embodiments disclosed herein also relate to temperature compensating a programmable duplexer based upon one or more temperature indications. The one or more temperature indications may be based upon a temperature of a semiconductor circuit, a temperature of a substrate of a one-port resonator of the programmable duplexer, and/or a temperature of the one-port resonator. The resulting programmable duplexer has an added additional advantage of lessening the temperature variations of the programmable duplexer.
    Type: Grant
    Filed: February 13, 2012
    Date of Patent: January 26, 2016
    Assignee: RF Micro Devices, Inc.
    Inventor: Joshua J. Caron
  • Patent number: 9246460
    Abstract: A power management system, which includes a parallel amplifier circuit and a switch mode power supply converter, is disclosed. The switch mode power supply converter cooperatively operates with the parallel amplifier circuit to form the power management system. The power management system operates in one of a high power modulation mode, a medium power modulation mode, and a low power average power tracking mode. Further, during the high power modulation mode and the medium power modulation mode, the power management system controls a power amplifier supply voltage to a radio frequency power amplifier to provide envelope tracking. During the low power average power tracking mode, the power management system controls the power amplifier supply voltage to the radio frequency power amplifier to provide average power tracking.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: January 26, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Nadim Khlat, Michael R. Kay, Phillippe Gorisse, Christopher Truong Ngo
  • Patent number: 9244478
    Abstract: Self-biasing transistor switching circuitry includes a main transistor, a biasing transistor, a first capacitor, and a second capacitor. The body of the main transistor is isolated from the gate, the drain, and the source of the main transistor by an insulating layer. The first capacitor is coupled between the source and the gate of the main transistor. The second capacitor is coupled between the source and the body of the main transistor. The body and the drain of the main transistor are coupled together. The gate and the drain of the biasing transistor are coupled to the gate of the main transistor. The drain of the biasing transistor is coupled to the drain of the main transistor. The self-biasing transistor switching circuitry is adapted to receive an oscillating signal at the drain of the main transistor, and use the oscillating signal to appropriately bias the main transistor.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: January 26, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Nathaniel Peachey, Ralph Christopher Nieri
  • Patent number: 9240770
    Abstract: Disclosed is a harmonic cancellation circuit for an RF switch branch having a first transistor with a first gate terminal and a first body terminal, a second transistor having a second gate terminal coupled to the first body terminal, and having a second body terminal coupled to the first gate terminal. Also included is a first resistor coupled between a first coupling node and the second body terminal, and a second resistor coupled between a second coupling node and the first body terminal, wherein the first transistor and second transistor are adapted to generate an inverse phase third harmonic signal relative to a third harmonic signal generated by the RF switch branch, such that the inverse phase third harmonic signal is output through the first resistor and the second resistor to the RF switch branch to reduce the third harmonic signal.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: January 19, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Daniel Charles Kerr, Eric K. Bolton, Robert Andrew Phelps
  • Patent number: 9240776
    Abstract: Analog-to-digital pulse width modulation circuitry includes thermometer code generator circuitry, clock generator circuitry, delay selection circuitry, and an output stage. The thermometer code generator circuitry is adapted to generate a digital thermometer code based upon a received analog input voltage. The clock generator circuitry is adapted to generate a reference clock and a plurality of delayed clock signals. The delay selection circuitry is connected between the thermometer code generator circuitry and the clock generator circuitry, and is adapted to select one of the delayed clock signals to present to the output stage based upon the generated thermometer code. The selected delayed clock signal is delayed by an amount of time that is proportional to the generated thermometer code. The reference clock signal and the selected delayed clock signal are delivered to the output stage where they are used to generate a pulse width modulated output signal.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: January 19, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: David Zimlich, Joseph Hubert Colles, Ricke W. Clark, Chris Levesque
  • Patent number: 9235222
    Abstract: A hybrid voltage regulator includes a shunt circuit, a shunt feedback circuit, a pass circuit, and a bias controller. The bias controller is configured to control the pass circuit. The hybrid voltage regulator may also include a current source. This hybrid voltage regulator reduces current consumption at low load conditions (improving power efficiency and battery life, particularly for CMOS based regulators), and also provides wideband power supply rejection and fast transient response.
    Type: Grant
    Filed: May 16, 2013
    Date of Patent: January 12, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Wonseok Oh, Hyuntae Kim, Praveen Nadimpalli
  • Patent number: 9236957
    Abstract: RF switching circuitry includes an RF switch coupled between an input node and an output node. Distortion compensation circuitry is coupled in parallel with the RF switch between the input node and the output node. The RF switch is configured to selectively pass an RF signal from the input node to the output node based on a first switching control signal. The distortion compensation circuitry is configured to boost a portion of the RF signal that is being compressed by the RF switch when the amplitude of the RF signal is above a predetermined threshold by selectively injecting current into one of the input node or the output node. Boosting a portion of the RF signal that is being compressed by the RF switch allows a signal passing through the RF switch to remain substantially linear, thereby improving the performance of the RF switching circuitry.
    Type: Grant
    Filed: May 7, 2014
    Date of Patent: January 12, 2016
    Assignee: RF Micro Devices, Inc.
    Inventors: Eric K. Bolton, Daniel Charles Kerr, Marcus Granger-Jones