An adaptive radio frequency including an input, an output, at least one fixed passive inductor and at least one variable active inductor connected between the input and the output.

A PoDL system uses a gyrator for DC coupling of DC power from a PSE to a wire pair, and/or decoupling DC power from a wire pair for a PD. The gyrators obviate the use of discrete inductors for DC-coupling/decoupling and can be formed as an integrated circuit. The gyrators use a small integrated capacitor and invert and multiply the capacitor effect to emulate an inductor. The gyrators present a high impedance to AC current and a low impedance to DC current. Various gyrator designs, such as positive and negative polarity gyrators, and configurations are disclosed. Gyrators are described with analog current limit and power switch control, so multiple functions are integrated on the same IC chip.

A PoDL system uses a gyrator for DC coupling of DC power from a PSE to a wire pair, and/or decoupling DC power from a wire pair for a PD. The gyrators obviate the use of discrete inductors for DC-coupling/decoupling and can be formed as an integrated circuit. The gyrators use a small integrated capacitor and invert and multiply the capacitor effect to emulate an inductor. The gyrators present a high impedance to AC current and a low impedance to DC current. Various gyrator designs, such as positive and negative polarity gyrators, and configurations are disclosed. Gyrators are described with analog current limit and power switch control, so multiple functions are integrated on the same IC chip.

A PoDL system uses a gyrator for DC coupling of DC power from a PSE to a wire pair, and/or decoupling DC power from a wire pair for a PD. The gyrators obviate the use of discrete inductors for DC-coupling/decoupling and can be formed as an integrated circuit. The gyrators use a small integrated capacitor and invert and multiply the capacitor effect to emulate an inductor. The gyrators present a high impedance to AC current and a low impedance to DC current. Various gyrator designs, such as positive and negative polarity gyrators, and configurations are disclosed. Gyrators are described with analog current limit and power switch control, so multiple functions are integrated on the same IC chip.

A PoDL system uses a gyrator for DC coupling of DC power from a PSE to a wire pair, and/or decoupling DC power from a wire pair for a PD. The gyrators obviate the use of discrete inductors for DC-coupling/decoupling and can be formed as an integrated circuit. The gyrators use a small integrated capacitor and invert and multiply the capacitor effect to emulate an inductor. The gyrators present a high impedance to AC current and a low impedance to DC current. Various gyrator designs, such as positive and negative polarity gyrators, and configurations are disclosed. Gyrators are described with analog current limit and power switch control, so multiple functions are integrated on the same IC chip.

An apparatus has advanced amplifier Classes and low pass filter technologies for using software generated ascending or level waveforms that are effective when applying cardiac defibrillation and cardioversion waveforms which significantly reduce damage to the heart muscle. The apparatus comprises a waveform energy control system for delivering software generated waveforms comprising differentially driven Class D and Class B amplifier sections, wherein the Class D amplifier section produces Phase 1 ascending waveforms and has a programmable lowpass filter (LPF) and wherein the Class B amplifier section delivers hard-switched Phase 2 waveforms.

An apparatus has advanced amplifier Classes and low pass filter technologies for using software generated ascending or level waveforms that are effective when applying cardiac defibrillation and cardioversion waveforms which significantly reduce damage to the heart muscle. The apparatus comprises a waveform energy control system for delivering software generated waveforms comprising differentially driven Class D and Class B amplifier sections, wherein the Class D amplifier section produces Phase 1 ascending waveforms and has a programmable lowpass filter (LPF) and wherein the Class B amplifier section delivers hard-switched Phase 2 waveforms.

Certain aspects of the present disclosure provide an N-path filter implemented using a generalized impedance converter (GIC) circuit. The GIC circuit is configured such that the N-path filter has a desired frequency response, which may include a wide passband with steeper rejection than a conventional N-path filter with only a single pole in each filter path. Certain aspects of the present disclosure provide an N-path filter having a frequency response with multiple concurrent passbands. In certain aspects, the N-path filter with multiple passbands is implemented using the GIC circuit. In other aspects, the N-path filter may include a bandpass response circuit where an inductance of the bandpass response circuit may be implemented using gyrators.

A self-biased gyrator-based input receiver amplifies and equalizes single-ended signals. The input receiver implements inductive impedance useful for high-frequency peaking circuits using an active gyrator-C circuit comprising only resistive, capacitive, and transistor elements, which are easily and efficiently fabricated on a conventional integrated circuit. Transistors comprising the input receiver, along with resistive elements and capacitive elements may be implemented as digitally adjustable circuit elements, providing for adjustment of at least peak frequency, low-frequency gain, and termination impedance.

Certain aspects of the present disclosure provide an N-path filter implemented using a generalized impedance converter (GIC) circuit. The GIC circuit is configured such that the N-path filter has a desired frequency response, which may include a wide passband with steeper rejection than a conventional N-path filter with only a single pole in each filter path. Certain aspects of the present disclosure provide an N-path filter having a frequency response with multiple concurrent passbands. In certain aspects, the N-path filter with multiple passbands is implemented using the GIC circuit. In other aspects, the N-path filter may include a bandpass response circuit where an inductance of the bandpass response circuit may be implemented using gyrators.