Abstract: An optical position sensing system is disclosed. The system includes a substrate having a surface. A plurality of photodetectors are at multiple locations across the surface, each of the plurality of photodetectors providing detector pulse signals in response to receiving the light. The system further includes a processor that determines a phase shift between the transmitted light pulse signals and the respective detector pulse signals and applies a multi-path resolution operation to distinguish between the detector pulse signals representing the transmitted light pulse signals and those representing reflected light pulse signals. The processor also calculates a distance of a transmitting device from each of the photodetectors based on the determined phase shift and the multi-path resolution operation and calculates a multi-dimensional position of the transmitting device relative to the substrate based on the calculated distances.

Abstract: One example includes a system that is comprised of a speaker, an amplifier, a current sensor, and a compensator circuit. The speaker produces audio in response to an amplified analog input signal received at a speaker input. The amplifier receives an analog audio input signal and provides the amplified analog audio input signal to the speaker input. The current sensor senses current passing through the speaker and provides a current sensor signal indicative thereof. The compensator circuit applies a transfer function to the current sensor signal to provide a compensation signal as feedback into the analog audio input signal, the transfer function matching at least one of resistance and inductance of the speaker.

Abstract: A circuit includes an amplifier to amplify an input signal and generate an output signal. The circuit also includes a tuning network to tune frequency response of the amplifier. The tuning network includes at least one tunable capacitor, which includes at least one micro-electro mechanical system (MEMS) capacitor. The amplifier could include a first die, the at least one MEMS capacitor could include a second die, and the first die and the second die could be integrated in a single package. The at least one MEMS capacitor could include a MEMS superstructure over a control structure, which is to control the MEMS superstructure and tune the capacitance of the at least one MEMS capacitor.

Abstract: A first branch group circuit includes a first branch circuit receiving a first RF input signal and first control information; and a second branch circuit receiving the first input signal and second control information. Each of the first and second branch circuits includes a power amplifier. The second control information enables the second branch circuit to be switched on or off while the first branch circuit remains on. A second branch group circuit includes: a third branch circuit receiving a second RF input signal and third control information; and a fourth branch circuit receiving the second input signal and fourth control information. Each of the third and fourth branch circuits includes a power amplifier. The fourth control information enables the fourth branch circuit to be switched on or off while the third branch circuit remains on. A combiner combines output signals of the power amplifiers to produce an output signal.

Abstract: An outphasing amplifier includes a first class-E power amplifier having an output coupled to a first conductor and an input receiving a first RF drive signal. A first reactive element is coupled between the first conductor and a second conductor. A second reactive element is coupled between the second conductor and a third conductor. A second class-E power amplifier includes an output coupled to a fourth conductor and an input coupled to a second RF drive signal, a third reactive element coupled between the second and fourth conductors. Outputs of the first and second power amplifiers are combined by the first, second and third reactive elements to produce an output current in a load. An efficiency enhancement circuit is coupled between the first and fourth conductors to improve power efficiency at back-off power levels. Power enhancement circuits are coupled to the first and fourth conductors, respectively.

Abstract: Methods and apparatus for reducing electromagnetic interference in a power converter using phase hopping in conjunction with pulse width modulation are disclosed. An example power converter includes an input voltage to, when a control switching device receives a first voltage, increase an output voltage; and when the control switching device receives a second voltage, decrease the output voltage. The example power converter further includes a phase hopping generator to generate a phase varying signal corresponding to two or more phases, the phase varying signal corresponding to a reference voltage; and output the phase varying signal to control the control switching device.

Abstract: A circuit includes an amplifier to amplify an input signal and generate an output signal. The circuit also includes a tuning network to tune frequency response of the amplifier. The tuning network includes at least one tunable capacitor, which includes at least one micro-electro mechanical system (MEMS) capacitor. The amplifier could include a first die, the at least one MEMS capacitor could include a second die, and the first die and the second die could be integrated in a single package. The at least one MEMS capacitor could include a MEMS superstructure over a control structure, which is to control the MEMS superstructure and tune the capacitance of the at least one MEMS capacitor.

Abstract: For crest factor reduction in a first signal having first and second components, the first component is delayed. A second signal is generated in response to detecting that a peak in the first component exceeds a predetermined threshold. Amplitude of the peak in the first component is reduced in response to detecting that the peak in the first component exceeds the predetermined threshold. Reducing amplitude of the peak in the first component includes adding the second signal to the delayed first component.

Abstract: A multi-level, multi-branch outphasing amplifier (20-1) includes a first branch group circuit (22-1) including a first branch circuit (11) receiving a first RF input signal (S1(t)) and first control information (S11_Ctrl=VDD) and a second branch circuit (12) receiving the first input signal and second control information (S12_Ctrl). Each of the first (11) and second (12) branch circuits includes a power amplifier. The second control information enables the second branch circuit to be switched on or off while the first branch circuit (12) remains on. A second branch group circuit (22-2) includes a third branch circuit (21) receiving a second RF input signal (S2(t)) and third control information (S21_Ctrl=VDD) and a fourth branch circuit (22) receiving the second input signal (S2(t)) and fourth control information (S22_Ctrl). Each of the third and fourth branch circuits includes a power amplifier.

Abstract: One example includes a system that is comprised of a speaker, an amplifier, a current sensor, and a compensator circuit. The speaker produces audio in response to an amplified analog input signal received at a speaker input. The amplifier receives an analog audio input signal and provides the amplified analog audio input signal to the speaker input. The current sensor senses current passing through the speaker and provides a current sensor signal indicative thereof. The compensator circuit applies a transfer function to the current sensor signal to provide a compensation signal as feedback into the analog audio input signal, the transfer function matching at least one of resistance and inductance of the speaker.

Abstract: A circuit includes an amplifier configured to amplify an input signal and generate an output signal. The circuit also includes a tuning network configured to tune frequency response of the amplifier. The tuning network includes at least one tunable capacitor, where the at least one tunable capacitor includes at least one micro-electro mechanical system (MEMS) capacitor. The amplifier could include a first die, the at least one MEMS capacitor could include a second die, and the first die and the second die could be integrated in a single package. The at least one MEMS capacitor could include a MEMS superstructure disposed over a control structure, where the control structure is configured to control the MEMS superstructure and tune the capacitance of the at least one MEMS capacitor.

Abstract: Methods and apparatus for providing adaptive electromagnetic interference control in a power converter are disclosed. An example apparatus includes a current interface to measure an internal current of the power converter. The example apparatus further includes a performance determiner to determine a spur power of an output voltage of the power converter based on the measured internal current. The example apparatus further includes a ramp generator to adjust a hopping configuration of a ramp voltage based on the spur power.

Abstract: Methods and apparatus for providing adaptive electromagnetic interference control in a power converter are disclosed. An example apparatus includes a current interface to measure an internal current of the power converter. The example apparatus further includes a performance determiner to determine a spur power of an output voltage of the power converter based on the measured internal current. The example apparatus further includes a ramp generator to adjust a hopping configuration of a ramp voltage based on the spur power.

Abstract: Methods and apparatus for reducing electromagnetic interference in a power converter using phase hopping in conjunction with pulse width modulation are disclosed. An example power converter includes an input voltage to, when a control switching device receives a first voltage, increase an output voltage; and when the control switching device receives a second voltage, decrease the output voltage. The example power converter further includes a phase hopping generator to generate a phase varying signal corresponding to two or more phases, the phase varying signal corresponding to a reference voltage; and output the phase varying signal to control the control switching device.

Abstract: An outphasing amplifier includes a first class-E power amplifier having an output coupled to a first conductor and an input receiving a first RF drive signal. A first reactive element is coupled between the first conductor and a second conductor. A second reactive element is coupled between the second conductor and a third conductor. A second class-E power amplifier includes an output coupled to a fourth conductor and an input coupled to a second RF drive signal, a third reactive element coupled between the second and fourth conductors. Outputs of the first and second power amplifiers are combined by the first, second and third reactive elements to produce an output current in a load. An efficiency enhancement circuit is coupled between the first and fourth conductors to improve power efficiency at back-off power levels. Power enhancement circuits are coupled to the first and fourth conductors, respectively.

Abstract: An outphasing amplifier includes a first class-E power amplifier (16-1) having an output coupled to a first conductor (31-1) and an input receiving a first RF drive signal (S1(t)). A first reactive element (CA-1) is coupled between the first conductor and a second conductor (30-1). A second reactive element (LA-1) is coupled between the second conductor and a third conductor (32-1). A second class-E power amplifier (17-1) includes an output coupled to a fourth conductor (31-2) and an input coupled to a second RF drive signal (S2(t)), a third reactive element (CA-3) coupled between the second and fourth conductors. Outputs of the first and second power amplifiers are combined by the first, second and third reactive elements to produce an output current in a load (R). An efficiency enhancement circuit (LEEC-1) is coupled between the first and fourth conductors to improve power efficiency at back-off power levels. Power enhancement circuits (20-1,2) are coupled to the first and fourth conductors, respectively.

Abstract: Noise-shaped frequency hopping power converters are disclosed. An example noise-shaped frequency hopping power converter comprises a shaped number generator having a first output to output a noise-shaped selection signal and a power converter having a first input to receive an input voltage signal, a second input to receive a switching signal that is based on the noise-shaped selection signal, and a second output to output an output voltage signal based on the switching signal.

Abstract: For generating quantized signals, a quantized phase domain related to quantized phases of an input signal is generated. Vectors that the input signal may occupy are calculated based on the quantized phase domain. A first quantized phase of a first component of the input signal is generated per the quantized phase domain, and a second quantized phase of a second component of the input signal is generated per the quantized phase domain.

Abstract: Noise-shaped frequency hopping power converters are disclosed. An example noise-shaped frequency hopping power converter comprises a shaped number generator having a first output to output a noise-shaped selection signal and a power converter having a first input to receive an input voltage signal, a second input to receive a switching signal that is based on the noise-shaped selection signal, and a second output to output an output voltage signal based on the switching signal.

Abstract: At least one tone is generated. An output signal is generated in response to an input signal and the at least one tone. The output signal is modulated. The input signal and the at least one tone are represented in the modulated output signal. The at least one tone is outside a bandwidth of the input signal as represented in the modulated output signal. The modulated output signal is amplified. The at least one tone in the amplified signal is attenuated after the amplifying.