Abstract: A system and method is disclosed, to generate an AC signal having a positive and negative half-cycles, each comprising a plurality of PWM pulses each with an individually designated pulse width, the system comprising: a first clock circuit; a second, faster, clock circuit; clock ratio measurement circuitry configured to output a first measurement being a ratio of frequencies; a propagation delay circuit configured to measure a number of propagation elements through which a bit transition propagates within a second clock signal period; pulse data calculation element configured to determine pulse shaping data; and for each of the half-cycles, a respective pulse synthesis circuit configured to synthesise the respective plurality of PWM pulses, each pulse having a respective start defined by the first clock signal, and a pulse width defined by the pulse shaping data and synthesised from the second clock and an output pulse from the propagation delay circuit.

Abstract: A system and method is disclosed, to generate an AC signal having a positive and negative half-cycles, each comprising a plurality of PWM pulses each with an individually designated pulse width, the system comprising: a first clock circuit; a second, faster, clock circuit; clock ratio measurement circuitry configured to output a first measurement being a ratio of frequencies; a propagation delay circuit configured to measure a number of propagation elements through which a bit transition propagates within a second clock signal period; pulse data calculation element configured to determine pulse shaping data; and for each of the half-cycles, a respective pulse synthesis circuit configured to synthesise the respective plurality of PWM pulses, each pulse having a respective start defined by the first clock signal, and a pulse width defined by the pulse shaping data and synthesised from the second clock and an output pulse from the propagation delay circuit.

Abstract: Duty cycles of pulse width modulation (“PWM”) pulses are determined by measurements taken with respect to an internally generated clock signal. One of these measurements calculates, in a continuous dynamic manner, a ratio of the number of cycles of the internally generated clock signal to one or more cycles of a PWM clock signal utilized as a time base for generation of the PWM pulses. This clock ratio measurement designates how many cycles of the internally generated clock signal will be used to designate a first portion of a duty cycle for each PWM pulse. Another measurement is utilized to determine a fractional portion of a cycle of the internally generated clock signal that will be used to designate a second portion of the duty cycle for each PWM pulse.

Abstract: Duty cycles of pulse width modulation (“PWM”) pulses are determined by measurements taken with respect to an internally generated clock signal. One of these measurements calculates, in a continuous dynamic manner, a ratio of the number of cycles of the internally generated clock signal to one or more cycles of a PWM clock signal utilized as a time base for generation of the PWM pulses. This clock ratio measurement designates how many cycles of the internally generated clock signal will be used to designate a first portion of a duty cycle for each PWM pulse. Another measurement is utilized to determine a fractional portion of a cycle of the internally generated clock signal that will be used to designate a second portion of the duty cycle for each PWM pulse.

Abstract: An apparatus comprising: a first transmitter configured to transmit in a first channel defined by a first frequency band; a second transmitter configured to transmit in a second channel defined by a second frequency band; and a controller configured to control power transfer via the first channel in dependence upon an impedance of the first channel and an impedance of the second channel.