Abstract: Electrical balance duplexers (EBDs). An example EBD includes a differential TX port coupled to a first coil, a differential RX port coupled to a second coil, a differential ANT port coupled to a third coil, and a differential BAL port coupled to a fourth coil. In some cases, the first and second coils are arranged such that magnetic flux cancellation is achieved between the two, thus isolating the TX port from the RX port. In some cases, DC isolation exists between the coils. During operation, the first coil may electromagnetically couple with the third coil and the fourth coil, and the second coil may electromagnetically couple with the third coil and the fourth coil. In some example cases, the first and second coils are each in their own metallization layer, and the third and fourth coils are in the same layer.

Abstract: In an example, a system includes a BAW resonator. The system also includes a first heater configured to heat the BAW resonator, where the first heater is controlled by a first control loop. The system includes a circuit coupled to the BAW resonator. The system also includes a second heater configured to heat the circuit, where the second heater is controlled by a second control loop.

Abstract: A system includes a first differential amplifier and a first transformer with a primary coil coupled to an output of the first differential amplifier and with a secondary coil coupled to a load. The system also includes a second differential amplifier and a second transformer with a primary coil coupled to an output of the second differential amplifier and with a secondary coil coupled in series with the secondary coil of the first transformer. The system also includes a tuning network coupled to a center tap node between the secondary coil of the first transformer and the secondary coil of the second transformer.

Abstract: A frequency multiplier includes an input section having inputs to receive an input signal having an input frequency, a mixer section, and an output section magnetically coupled to the input section and generating an output signal in response to the input signal. The mixer section may be coupled to the input section by a common mode node forming a path for a common mode current to flow to the mixer section and be magnetically coupled to the common mode node. The input section may generate a signal current, and the mixer section may be magnetically coupled to the input section and be directly capacitively coupled to the input section through a capacitor in a signal current path. The mixer section may have differential inputs capacitively coupled to the input section and also be coupled to the input section through a current path. A current helper section may be coupled to the current path.

Abstract: In an example, a system includes a BAW resonator. The system also includes a first heater configured to heat the BAW resonator, where the first heater is controlled by a first control loop. The system includes a circuit coupled to the BAW resonator. The system also includes a second heater configured to heat the circuit, where the second heater is controlled by a second control loop.

Abstract: An on-chip directional coupler includes a first linear conductive trace, a second linear conductive trace, and a conductive loop. The first linear conductive trace including an end and a coupled port. The second linear conductive trace is spaced apart from and parallel to the first linear conductive trace. The second linear conductive trace includes an end and an isolated port. The conductive loop includes a first end conductively coupled to the end of the first linear conductive trace, and a second end conductively coupled to the end of the second linear conductive trace.

Abstract: A frequency multiplier includes an input section having inputs to receive an input signal having an input frequency, a mixer section, and an output section magnetically coupled to the input section and generating an output signal in response to the input signal. The mixer section may be coupled to the input section by a common mode node forming a path for a common mode current to flow to the mixer section and be magnetically coupled to the common mode node. The input section may generate a signal current, and the mixer section may be magnetically coupled to the input section and be directly capacitively coupled to the input section through a capacitor in a signal current path. The mixer section may have differential inputs capacitively coupled to the input section and also be coupled to the input section through a current path. A current helper section may be coupled to the current path.

Abstract: An oscillator includes: a bulk-acoustic wave (BAW) resonator having a first BAW resonator terminal and a second BAW resonator terminal; and an active circuit coupled to the first and second BAW resonator terminals and having a series resonance topology with: a first transistor; a second transistor; a first resistor; a second resistor; a capacitive network coupled to first and second BAW resonator terminals and to respective current terminals of the first and second transistors; and an inductor having a first inductor terminal and a second inductor terminal, the first inductor terminal coupled to the capacitive network, and the second inductor terminal coupled to ground terminal.

Abstract: A system includes a first differential amplifier and a first transformer with a primary coil coupled to an output of the first differential amplifier and with a secondary coil coupled to a load. The system also includes a second differential amplifier and a second transformer with a primary coil coupled to an output of the second differential amplifier and with a secondary coil coupled in series with the secondary coil of the first transformer. The system also includes a tuning network coupled to a center tap node between the secondary coil of the first transformer and the secondary coil of the second transformer.

Abstract: A frequency multiplier includes an input section to receive a quadrature phase input signal having an input frequency, a mixer section coupled to the input section by a common mode node that forms a path for the common mode signal current to flow to the mixer section and magnetically coupled to the common mode node or capacitively coupled to the input section to generate a differential switching voltage at odd multiples of twice the input frequency, which switching voltage is applied to inputs of the mixer section, and an output section magnetically coupled to the mixer section, the output section being configured to generate an output voltage having a dominate frequency and sub-dominate frequencies spaced apart by the first multiple, the dominate frequency of the output voltage being a second multiple of the input frequency, where the second multiple is greater than the first multiple. Various arrangements are provided.

Abstract: A device includes a MEMS resonator and oscillator circuit coupled to the MEMS resonator. The circuit includes a first transistor having a first control terminal and first and second current terminals, and a second transistor having a second control terminal and third and fourth current terminals. The circuit includes a resonator coupling network configured to inductively couple MEMS resonator terminals to the first and third current terminals, and to couple the first and third current terminals. The circuit includes a control terminal coupling network configured to couple the first and second control terminals, and to reduce a voltage swing at the first and second control terminals relative to a voltage swing at the first and third current terminals. The circuit includes a second terminal coupling network configured to couple the second and fourth current terminals. A second terminal coupling network resonant frequency is approximately that of MEMS resonator.

Abstract: A voltage controlled oscillator (VCO) circuit is disclosed. The VCO circuit comprises a VCO tuning circuit comprising a primary inductive coil. In some embodiments, the VCO tuning circuit is configured to generate a VCO output signal at a first resonance frequency. The VCO circuit further comprises a filter circuit comprising a secondary inductive coil. In some embodiments, the filter circuit is configured to resonate at a second, different, resonance frequency, in order to filter a noise associated with the VCO tuning circuit. In some embodiments, the primary inductive coil associated with the VCO tuning circuit and the secondary inductive coil associated with the filter circuit are concentrically arranged with respect to one another. Further, in some embodiments, the primary inductive coil associated with the VCO tuning circuit and the secondary inductive coil associated with the filter circuit are magnetically decoupled with respect to one another.

Abstract: A voltage controlled oscillator (VCO) circuit is disclosed. The VCO circuit comprises a VCO tuning circuit comprising a primary inductive coil. In some embodiments, the VCO tuning circuit is configured to generate a VCO output signal at a first resonance frequency. The VCO circuit further comprises a filter circuit comprising a secondary inductive coil. In some embodiments, the filter circuit is configured to resonate at a second, different, resonance frequency, in order to filter a noise associated with the VCO tuning circuit. In some embodiments, the primary inductive coil associated with the VCO tuning circuit and the secondary inductive coil associated with the filter circuit are concentrically arranged with respect to one another. Further, in some embodiments, the primary inductive coil associated with the VCO tuning circuit and the secondary inductive coil associated with the filter circuit are magnetically decoupled with respect to one another.

Abstract: A quadrature voltage controlled oscillator (QVCO). The QVCO includes a first node for providing a first quadrature signal, a second node for providing a second quadrature signal, a third node for providing a third quadrature signal, and a fourth node for providing a fourth quadrature signal. The QVCO further includes a first coil connected between the first node and the second node and a second coil connected between the third node and the fourth node. The first coil and second coil are positively magnetically coupled.

Abstract: A quadrature voltage controlled oscillator (QVCO). The QVCO includes a first node for providing a first quadrature signal, a second node for providing a second quadrature signal, a third node for providing a third quadrature signal, and a fourth node for providing a fourth quadrature signal. The QVCO further includes a first coil connected between the first node and the second node and a second coil connected between the third node and the fourth node. The first coil and second coil are positively magnetically coupled.

Abstract: A voltage controlled oscillator (VCO) for providing an oscillating output signal. The VCO includes a first inductor, and the oscillating output signal is responsive to a changing current through the first inductor. The VCO also includes a second inductor, proximate the first inductor, coupled to a first cross-coupling stage and a third inductor, proximate the first inductor, coupled to a second cross-coupling stage.

Abstract: A quadrature voltage controlled oscillator (QVCO). The QVCO includes a first node for providing a first quadrature signal, a second node for providing a second quadrature signal, a third node for providing a third quadrature signal, and a fourth node for providing a fourth quadrature signal. The QVCO further includes a first coil connected between the first node and the second node and a second coil connected between the third node and the fourth node. The first coil and second coil are positively magnetically coupled.

Abstract: A quadrature voltage controlled oscillator (QVCO) for providing an oscillating output signal. The QVCO includes a first oscillating circuit for producing a first output signal and a second output signal, those signals being a first set of antiphase signals. The QVCO also includes a second oscillating circuit for producing a first output signal and a second output signal, those signals being a second set of antiphase signals. The first oscillating circuit also has injection circuitry for injecting the second set of antiphase signals without a DC bias into the first output signal and the second output signal, and the second oscillating circuit also has injection circuitry for injecting the first set of antiphase signals without a DC bias into the third output signal and the fourth output signal.

Abstract: A linear transform can be performed using a passive analog multi-stage charge re-use linear transform circuit. The passive analog multi-stage charge re-use linear transform circuit transforms an input analog circuit to generate a transformed analog output signal. The passive analog multi-stage charge re-use linear transform circuit may be included in a software defined radio (SDR), where the transformed analog output signal may be output to an analog-to-digital converter (ADC) of the SDR device so as to enable the ADC to perform wideband spectrum sensing. The passive analog multi-stage charge re-use linear transform circuit may also be included in a beamforming device so as to enable the device to perform spectral shifting and spatial shifting of signals. This passive analog multi-stage charge re-use linear transform circuit may promote reduced power consumption in comparison to other circuits while also supporting wideband applications at high sampling rates.

Abstract: A linear transform can be performed using a passive analog multi-stage charge re-use linear transform circuit. The passive analog multi-stage charge re-use linear transform circuit transforms an input analog circuit to generate a transformed analog output signal. The passive analog multi-stage charge re-use linear transform circuit may be included in a software defined radio (SDR), where the transformed analog output signal may be output to an analog-to-digital converter (ADC) of the SDR device so as to enable the ADC to perform wideband spectrum sensing. The passive analog multi-stage charge re-use linear transform circuit may also be included in a beamforming device so as to enable the device to perform spectral shifting and spatial shifting of signals. This passive analog multi-stage charge re-use linear transform circuit may promote reduced power consumption in comparison to other circuits while also supporting wideband applications at high sampling rates.