The speaker coil in a dynamic speaker in a mobile computing device can be used to generate radio frequency (RF) signals having a frequency of about 100 kHz or greater. A speaker amplifier drives the dynamic speaker to produce sound and RF circuitry drives the speaker amplifier to generate the RF signals having a frequency of about 100 kHz or greater. The speaker coil can comprise a tap at an appropriate point between the ends of the coil to cause the coil to operate at resonance over a desired RF frequency band. A low-pass filter can be positioned at the speaker amplifier output to protect the speaker amplifier from RF energy generated by the RF circuitry and a high-pass filter can be positioned at the output of the RF circuitry to protect the RF circuitry from audio energy generated by the speaker amplifier.

A receiver circuit is disclosed. The receiver circuit includes an amplifier configured to generate an RF signal based on a received signal, where the RF signal includes an information signal and a blocker signal modulating an RF carrier frequency. The receiver circuit also includes an RF filter connected to the amplifier, where the RF filter is configured to selectively attenuate the blocker signal.

A receiver circuit is disclosed. The receiver circuit includes an amplifier configured to generate an RF signal based on a received signal, where the RF signal includes an information signal and a blocker signal modulating an RF carrier frequency. The receiver circuit also includes an RF filter connected to the amplifier, where the RF filter is configured to selectively attenuate the blocker signal.

Proposed are a device for supporting height growth by using a pulsed micro-electromagnetic field, and a method for driving the device. According to an embodiment, the device may include an antenna band part including a first antenna and a second antenna which are provided inside a covering part that is configured to surround a joint and which are configured to generate a micro-magnetic field at the joint in a contactless manner, and may include a control unit configured to generate the micro-magnetic field by forming a high frequency voltage and providing the high frequency voltage to the antenna band part, the control unit being configured to adjust the formed high frequency voltage, on the basis of a sensing value of a micro-electromagnetic field sensed at the second antenna, such that a micro-magnetic field corresponding to a diameter of the joint is provided.

Proposed are a device for supporting height growth by using a pulsed micro-electromagnetic field, and a method for driving the device. According to an embodiment, the device may include an antenna band part including a first antenna and a second antenna which are provided inside a covering part that is configured to surround a joint and which are configured to generate a micro-magnetic field at the joint in a contactless manner, and may include a control unit configured to generate the micro-magnetic field by forming a high frequency voltage and providing the high frequency voltage to the antenna band part, the control unit being configured to adjust the formed high frequency voltage, on the basis of a sensing value of a micro-electromagnetic field sensed at the second antenna, such that a micro-magnetic field corresponding to a diameter of the joint is provided.

In some embodiments, a power supply system for a power amplifier can include a voltage converter implemented generate a first voltage at an output node, and an envelope following circuit implemented to generate and combine a second voltage with the first voltage to provide a combined output voltage for the power amplifier. The combined output voltage can have a waveform that follows one or more peaks of an envelope of a radio-frequency signal above the first voltage.

Various embodiments provide systems, devices, and methods for a multi-core digital power amplifier with an unbalanced power combiner. In one example, two or more cores are combined with a transformer section that has a first coupling coefficient and another two or more cores are combined with a second transformer section that has a second coupling coefficient that is different than the first coupling coefficient. The outputs of different cores may be cross-coupled with the primary inductors of the transformers. The digital power amplifier may provide an output power that is flat over a relatively wide operating range. Other embodiments may be described and claimed.

Various embodiments provide systems, devices, and methods for a multi-core digital power amplifier with an unbalanced power combiner. In one example, two or more cores are combined with a transformer section that has a first coupling coefficient and another two or more cores are combined with a second transformer section that has a second coupling coefficient that is different than the first coupling coefficient. The outputs of different cores may be cross-coupled with the primary inductors of the transformers. The digital power amplifier may provide an output power that is flat over a relatively wide operating range. Other embodiments may be described and claimed.

Implementations disclosed describe a programmable analog subsystem (PASS) having a plurality of reconfigurable analog circuits. The PASS may be coupled to an input/output device to receive an input signal and to an interface to communicate data with a central processing unit. In a first PASS configuration, with the plurality of reconfigurable analog circuits having a first configuration setting, the PASS may process the input signal through the plurality of reconfigurable analog circuits to generate a first output value based on the input signal. Responsive to the first output value, the PASS may reconfigure the plurality of reconfigurable analog circuits into a second PASS configuration having a second configuration setting, such that the second configuration setting is different than the first configuration setting.

Implementations disclosed describe a programmable analog subsystem (PASS) having a plurality of reconfigurable analog circuits. The PASS may be coupled to an input/output device to receive an input signal and to an interface to communicate data with a central processing unit. In a first PASS configuration, with the plurality of reconfigurable analog circuits having a first configuration setting, the PASS may process the input signal through the plurality of reconfigurable analog circuits to generate a first output value based on the input signal. Responsive to the first output value, the PASS may reconfigure the plurality of reconfigurable analog circuits into a second PASS configuration having a second configuration setting, such that the second configuration setting is different than the first configuration setting.