Back to results
US 9,287,826 B2Granted
Sine-cosine modulator
AssigneeConta Pronat GmbH
InventorStefan Wehmeier
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeConta Pronat GmbH
InventorStefan Wehmeier
Estimating the term…
The invention relates to a self-oscillating pulse-width modulation amplifier in the form of a sine-cosine modulator (10) comprising at least two comparators (13, 14), two integrators (11, 12), a power switching stage (15), and negative feedback coupling with a low-frequency signal input and output. To achieve a maximum modulation factor, there are provisions with the aid of the comparators (13, 14) and integrators (11, 12) for the generation of sine- and cosine-square-wave voltages and sine- and co-sine-triangle-wave voltages that drive the power switching stage (15) in part, wherein the output of the power switching stage (15) combined with an LC low-pass filter (16) forms the low-frequency signal output. This brings about a situation in which a stable natural frequency exists and the modulation factor can be increased to nearly 100%. At the same time, a very low level of distortion is achieved and no distortion components higher than K3 arise, so there is a significant improvement vis-a-vis the known pulse-width modulation amplifiers.
Sine-cosine modulator comprising a first integrator, a first comparator, a second integrator and a second comparator connected in series, said integrators and comparators also serving to create a phase shift of 90° with respect to their input signal, a power switching stage, an LC low-pass filter, as well as a low-frequency signal input or control-voltage input and a low-frequency signal output or DC voltage output,
Dependencies are inferred from the claim text.