Class D amplifier with increased efficiency
View Patent ↗The present invention is a method of operating a speaker by converting an audio signal to a pulse-width modulated signal that has a plurality of positive pulses and a plurality of negative pulses as a function of the audio signal, then driving an H-bridge circuit interconnected to a speaker, wherein the H-bridge circuit comprises an A-side and a B-side, wherein the A-side comprises a first switching transistor and a second switching transistor, and wherein the B-side comprises a first switching transistor and a second switching transistor. For each positive pulse, the A-side of the H-bridge circuit is driven by pushing the first switching transistor of the A-side while grounding the second switching transistor of the A-side. For each negative pulse, the B-side of the H-bridge circuit is driven by pushing the first switching transistor of the B-side while grounding the second switching transistor of the B-side.
1. A method of operating a speaker comprising:
a) converting an audio signal to a pulse-width modulated signal comprising a plurality of positive pulses and a plurality of negative pulses as a function of the audio signal;
b) driving an H-bridge circuit interconnected to a speaker, wherein the H-bridge circuit comprises an A-side and a B-side, wherein the A-side comprises a first switching transistor and a second switching transistor, and wherein the B-side comprises a first switching transistor and a second switching transistor; comprising the steps of:
i) driving, for each positive pulse, the A-side of the H-bridge circuit by pushing the first switching transistor of the A-side while grounding the second switching transistor of the A-side and grounding the first switching transistor of the B-side; and
ii) driving, for each negative pulse, the B-side of the H-bridge circuit by pushing the first switching transistor of the B-side while grounding the second switching transistor of the B-side and grounding the first switching transistor of the A-side.
2. The method of claim 1 further comprising driving the speaker as a function of driving the A-side and the B-side of the H-bridge circuit.
3. The method of claim 1 further comprising receiving the audio signal from an associated security system component.
4. A circuit for driving a speaker comprising:
a) a processor circuit adapted to convert an audio signal to a pulse-width modulated signal comprising a plurality of positive pulses and a plurality of negative pulses as a function of the audio signal;
b) an H-bridge circuit interconnected to a speaker, wherein the H-bridge circuit comprises an A-side and a B-side, wherein the A-side comprises a first switching transistor and a second switching transistor, and wherein the B-side comprises a first switching transistor and a second switching transistor;
c) first circuitry adapted to drive, for each positive pulse, the A-side of the H-bridge circuit by pushing the first switching transistor of the A-side while grounding the second switching transistor of the A-side and grounding the first switching transistor of the B-side; and
d) second circuitry adapted to drive, for each negative pulse, the B-side of the H-bridge circuit by pushing the first switching transistor of the B-side while grounding the second switching transistor of the B-side and grounding the first switching transistor of the A-side.