Abstract:
Methods, apparatus, systems and articles of manufacture to efficiently transfer power wirelessly are disclosed. An example apparatus includes a feedback loop to when a second current value is greater than a first current value, change a direction value, the second current value being obtained after the first current value; when the second current value is less than the first current value, maintain the direction value; and a summer to when the direction value corresponds to a first direction value, increase a reference signal by a step size; and when the direction value corresponds to a second direction value different than the first direction value, decrease the reference signal by the step size.
Abstract:
A resonant power transfer system includes resonant circuitry (26) including an inductor coil (59) and a resonant capacitor (51) coupled to a first terminal (27) of the inductor coil, wherein the inductor coil and the resonant capacitor resonate to produce an excitation signal (IS) and a state variable signal (VCS1). Sub-sampling circuitry (30) samples first and second points of the state variable signal at a rate which is substantially less than the RF frequency of the state variable signal. Information recovery circuitry (32) produces a state variable parameter signal representing a parameter (A) of the state variable signal from information in the first and second sampled points. Control circuitry (38) produces a first control signal in response to the state variable parameter signal. Detection and optimization circuitry (41) produces a second control signal in response to the state variable parameter signal. Voltage regulation circuitry (45) produces a regulated supply voltage in response to the first control signal. Switching inverter circuitry produces the excitation signal in response to the regulated supply voltage and the second control signal.
Abstract:
An inductive structure includes a power coil and a data coil. The data coil is substantially centered within the power coil. A first portion of the data coil conducts current in a first direction. A second portion of the data coil conducts current in a second direction opposite the first direction. The first portion of the data coil is connected at a node to the second portion of the data coil. The node is coupled to a ground.
Abstract:
A sampling phase locked loop (PLL) circuit includes a pull-up/down buffer configured to convert an oscillator reference clock into a square wave sampling control signal input to a sampling phase detector. The buffer circuit is configured to reduce power by controlling the switching of the pull-up and pull-down transistors (and thereby the transitions of the sampling control signal) so that the transistors are not on at the same time.
Abstract:
Methods, apparatus, systems and articles of manufacture are disclosed to measure a resonant sensor based on detection of group delay. An example apparatus includes a modulation manager configured to query the resonant sensor with a modulated signal including a frequency; and a resonance determiner configured to determine a resonance frequency of the resonant sensor based on a group delay associated with the resonant sensor and the frequency.
Abstract:
In described examples, an inductive structure includes a power coil and a data coil. The data coil is substantially centered within the power coil. A first portion of the data coil is for conducting current in a first direction. A second portion of the data coil is for conducting current in a second direction opposite the first direction. The first portion of the data coil is connected at a ground node to the second portion of the data coil. The power coil is for: receiving power without data; and outputting the received power without data.
Abstract:
A resonant power transfer system includes resonant circuitry (26) including an inductor coil (59) and a resonant capacitor (51) coupled to a first terminal (27) of the inductor coil, wherein the inductor coil and the resonant capacitor resonate to produce an excitation signal (IS) and a state variable signal (VCS1). Sub-sampling circuitry (30) samples first and second points of the state variable signal at a rate which is substantially less than the RF frequency of the state variable signal. Information recovery circuitry (32) produces a state variable parameter signal representing a parameter (A) of the state variable signal from information in the first and second sampled points. Control circuitry (38) produces a first control signal in response to the state variable parameter signal. Detection and optimization circuitry (41) produces a second control signal in response to the state variable parameter signal. Voltage regulation circuitry (45) produces a regulated supply voltage in response to the first control signal. Switching inverter circuitry produces the excitation signal in response to the regulated supply voltage and the second control signal.
Abstract:
A removable module includes circuitry, a near field communication (NFC) coupler to provide a data signal to the circuitry, and a second NFC coupler to supply operating voltage to the circuitry.
Abstract:
In described examples, an inductive structure includes a power coil and a data coil. The data coil is substantially centered within the power coil. A first portion of the data coil is for conducting current in a first direction. A second portion of the data coil is for conducting current in a second direction opposite the first direction. The first portion of the data coil is connected at a ground node to the second portion of the data coil. The power coil is for: receiving power without data; and outputting the received power without data.
Abstract:
A removable module includes circuitry, a near field communication (NFC) coupler to provide a data signal to the circuitry, and a second NFC coupler to supply operating voltage to the circuitry.