KR20140097874A - Audio apparartus and control method thereof - Google Patents

Audio apparartus and control method thereof Download PDF

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Publication number
KR20140097874A
KR20140097874A KR1020130010538A KR20130010538A KR20140097874A KR 20140097874 A KR20140097874 A KR 20140097874A KR 1020130010538 A KR1020130010538 A KR 1020130010538A KR 20130010538 A KR20130010538 A KR 20130010538A KR 20140097874 A KR20140097874 A KR 20140097874A
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South Korea
Prior art keywords
signal
output
error
unit
switching
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KR1020130010538A
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Korean (ko)
Inventor
이재철
김병수
조기영
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삼성전자주식회사
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Priority to KR1020130010538A priority Critical patent/KR20140097874A/en
Publication of KR20140097874A publication Critical patent/KR20140097874A/en

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/21—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only
    • H03F3/217—Class D power amplifiers; Switching amplifiers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/04—Circuits for transducers, loudspeakers or microphones for correcting frequency response

Abstract

The present invention provides an audio device, which feeds back an output signal even when an input signal and the output signal have different waveforms, compensates for a nonlinear property and error of the audio device, and improves performance on a voice signal of the audio device, and a control method therefor. The audio device is characterized in comprising a modulating unit which modulates an input signal; a plurality of switching units which perform switching corresponding to the signal modulated by the modulating unit to drive a speaker; and a compensating unit which compares an error compensation signal outputted from output terminals of the switching units and compensates for an error in an output signal for driving the speaker based on a compared result. According to the present invention, the output signal can be fed back to compensate for a nonlinear property and an error of the audio device, even when input and output signals have different waveforms. The audio device can guarantee audio performance by compensating for an error to overcome a disadvantage of a multilevel switching amplifier which is incurred by the fact error compensation even when switching efficiency is improved. Therefore, a switching amplifier system including the audio device can be effectively configured.

Description

AUDIO APPARATUS AND CONTROL METHOD THEREOF [0001]

The present invention relates to an audio apparatus and a control method thereof, and more particularly, to an audio apparatus capable of improving the performance of an audio apparatus by improving an output signal for driving a speaker, To an audio apparatus capable of correcting nonlinear characteristics and errors of an audio apparatus by implementing feedback of an output signal even if the waveform is non-linear.

Of the current audio devices, switching amplifiers are binary-based, two-stage switching at high output, binary at low output, and multilevel at higher output. Among the multilevel methods, the damped ternary method is used in a multilevel manner because of its high efficiency. However, in the case of the damped ternary method, since the PWM (Pulse Width Modulation) output waveform is calculated by calculation, it is difficult to correct the error by the feedback.

1 is an exemplary diagram showing a configuration of a conventional audio apparatus. Conventionally, the switching timing is calculated for multilevel switching. Since the calculated switching signal is different from the input signal, it may be difficult to compare the input signal with the output signal by feedbacking the output waveform. Therefore, it is general that the multi-level switching amplifier constitutes the circuit without feedback.

FIG. 2 is an exemplary diagram showing a three-step operation of a damped ternary method. The damped ternary method generates efficiency by operating a zero power stage. In general multilevel, sw1 and sw2 are turned on and sw3 and sw4 are turned off. In a multilevel switching amplifier for efficiency improvement, such as a damped ternary, such an operation is not performed for efficiency.

 3 is an exemplary diagram for comparing a power source and a waveform of a binary system and a damped ternary system. As shown in FIG. 3, a gain of a damped ternary method is shown as compared with a binary method for obtaining a sinusoidal curve as an output signal. In the case of the binary method, since a small power source is used for two large signals whose operation is canceled or not used, high power is consumed and power consumption is increased. However, the Damped Ternary method is effective because it generates the output signal of the sine curve while supplying the power only when the signal exists.

However, in the case of the structure that calculates and outputs the waveform of the PWM (Pulse Width Modulation) output, there is a problem that the waveforms of the input signal and the output signal are not the same, so that the feedback correction can not be performed. Failure to perform the feedback correction can not correct the nonlinear characteristics of the switching amplifier, thereby degrading the performance of the audio apparatus.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problems of the conventional audio apparatus described above and to provide an audio apparatus in which feedback of an output signal for driving a speaker is implemented even in a waveform in which an input signal and an output signal for driving a speaker are not the same, Characteristics and errors of the audio signal, and a control method thereof.

According to an aspect of the present invention, there is provided an audio apparatus including: a modulator for modulating an input signal; A plurality of switching units for switching the speaker to correspond to the signal modulated by the modulator to drive the speaker; And a correction section for comparing an error correction signal outputted from an output terminal of the plurality of switching sections with the input signal and correcting an error of an output signal for driving the speaker based on a result of the comparison have.

Here, the speaker may be located between the output terminals of the plurality of switching units.

The apparatus of claim 1, further comprising a filter unit for filtering the signals switched from the plurality of switching units, wherein the correcting unit corrects the output from at least one of an output terminal between the plurality of switching units and the filter unit, The error correction signal is compared with the input signal, and the error of the output signal for driving the speaker is corrected based on the comparison result.

The signal modifying unit may further include a signal modifying unit that modifies a plurality of output signals output from the output terminals of the plurality of switching units into the error correction signal, To the error correction signal, compares the changed error correction signal with the input signal, and corrects the error of the output signal for driving the speaker based on the comparison result.

The correction unit may change a plurality of output signals output from at least one output end of the output unit between the plurality of switching units and the filter unit and the output unit of the rear end of the filter unit by the signal changing unit to the error correction signal The error correction signal may be compared with the input signal to correct the error of the output signal for driving the speaker based on the comparison result.

According to another aspect of the present invention, there is provided a method of controlling an audio apparatus, the method comprising: modulating an input signal and outputting the modulated signal; Driving the speaker by switching to correspond to the modulated signal; And comparing the input signal with an error correction signal output from an output terminal of a plurality of switching units for switching to drive the speaker and correcting an error of an output signal for driving the speaker based on a result of the comparison Can be achieved by a control method of an audio device.

Here, the speaker may be located between the output terminals of the plurality of switching units.

The error correction step may include comparing the error correction signal output from the output terminal between the plurality of switching units and the filter unit and the output terminal of the output unit of the filter unit with the input signal, And correcting an error of the output signal for driving the speaker based on the result.

Here, the step of correcting the error may include changing a plurality of output signals output from the output terminals of the plurality of switching units by the signal changing unit to the error correction signal, comparing the changed error correction signal with the input signal And correcting an error of the output signal for driving the speaker based on the comparison result.

And correcting the error by correcting a plurality of output signals output from at least one of an output end between the plurality of switching units and the filter unit and an output end of the rear end of the filter unit by the signal changing unit, And correcting the error of the output signal for driving the speaker based on a result of the comparison.

According to the present invention, an output signal for driving a speaker can be improved to improve the performance of an audio apparatus. Even if a waveform in which an input signal and an output signal for driving a speaker are not the same, Feedback is implemented to correct the non-linear characteristics and errors of the audio apparatus.

1 is an exemplary diagram showing the configuration of a conventional audio apparatus,
FIG. 2 is an exemplary diagram showing a three-step operation of a damped ternary method,
3 is an exemplary diagram for comparing a power source and a waveform of a binary system and a damped ternary system,
4 is a block diagram showing the configuration of an audio apparatus according to the present invention,
5 to 7 are circuit diagrams illustrating a configuration of an audio apparatus according to an embodiment of the present invention,
8 is a control flowchart of an audio apparatus according to the present invention,
9 is a control flowchart of an audio apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. Parts which are not directly related to the present invention are omitted for convenience of description, and the same or similar components are denoted by the same reference numerals throughout the specification.

4 is a block diagram showing a configuration of an audio apparatus 1 according to the present invention. The audio apparatus 1 shown in FIG. 4 may include a modulation unit 110, a switching unit 120, and a correction unit 100.

The modulator 110 converts the input signal into a PWM signal and outputs the PWM signal. The modulation unit 110 may be provided to calculate the PWM signal so that the switching of the switching unit 120 is minimized. The modulation unit 110 may be configured by a combination of a transistor, a diode, etc., which is a modulation element, and a modulation element.

The switching unit 120 outputs the switching signal of the PWM by the signal received from the modulation unit 110. The speaker can be driven by switching to correspond to the signal modulated by the modulation unit 110. [ The switching unit 120 may be composed of a plurality of bridging circuits of a bridge tied load (BTL), and may be considered as a modified circuit. The switching unit 120 changes the path of the voltage current according to the polarity of the input signal based on the configuration of the circuit. The switching unit 120 may be implemented by a metal oxide semiconductor field effect transistor (MOSFET).

The correction unit 100 may be provided with a DSP (Digital Signal Processor) and may include a comparator. The correction unit 100 corrects an error correction signal output from the output terminals of the plurality of switching units 120 The correction unit 100 compares the input signal with the input signal, and corrects the error of the output signal for driving the speaker based on the comparison result. The correction unit 100 performs signal filtering, amplification, noise removal, , And feature detection of signals, and basically can perform real-time digital processing of analog signals, thereby preventing distortion or loss of signals.

5 to 7 are circuit diagrams showing a configuration of an audio apparatus 1 according to an embodiment of the present invention.

5 to 7, an audio apparatus 1 according to an embodiment of the present invention includes a modulator 110, a switching unit 120, a filter unit 130, a power supply unit 150, And a calibration unit 100 including a calibration unit 100 and a calibration unit.

The power supply unit 150 supplies power for driving an internal device of the audio device 1. [

The modulation unit 110 may be provided so as to generate a PWM signal by calculating to minimize switching corresponding to the plurality of switching units 120. [ The modulation unit 110 may include a comparator, and may output the generated PWM signal to the switching unit 120 through a comparator. The comparing unit of the modulating unit 110 may be provided to correspond to the switching unit 120 connected in the signal direction so that the switching may be minimized.

The filter unit 130 may be provided with an inductor and may include a capacitor. The filter unit 130 functions to suppress a sudden change of the current by inducing a voltage proportional to the change amount of the current. The filter unit 130 may filter the switched signals from the plurality of switching units 120. The output signal output from the filter unit 130 may drive a speaker to output a voice signal. As described above, the speaker may be located between the output ends of the plurality of switching units 120, and more specifically, may be located between the two filter units 130 at the rear end of the plurality of switching units 120.

The signal changing unit 140 may change an output signal output from the output terminals of the plurality of switching units 120 to an error correction signal for correcting an error. In detail, the signal changing unit 140 converts the two signals into one, and the output signal has a + component and a - component, which can be made into one through the op amp. The signal changing unit 140 may be constituted by a circuit and included in the correcting unit 100.

The correction unit 100 compares the error correction signal output from the output terminal between the plurality of switching units 120 and the filter unit 130 and the output terminal of the output unit at the rear end of the filter unit 130 with the input signal, The error of the output signal for driving the speaker can be corrected on the basis of the comparison result.

5, the correcting unit 100 changes a plurality of output signals output from output points A1 and A2 between the plurality of switching units 120 and the filter unit 130 to an error correction signal , It is possible to compare the changed error correction signal with the input signal and to correct the error of the output signal for driving the speaker based on the comparison result.

6, the correction unit 100 changes a plurality of output signals output from the B1 and B2 output ends of the filter unit 130 to an error correction signal, and outputs a modified error correction signal, It is possible to compare the signals and to correct the error of the output signal for driving the speaker based on the comparison result.

7, the correcting unit 100 includes a plurality of switching units 120 and a plurality of switching units 120. The switching unit 120 is connected between the output terminals A1 and A2, the output terminals of the filter unit 130, The plurality of output signals output from the point can be changed to an error correction signal to compare the changed error correction signal with the input signal and to correct the error of the output signal for driving the speaker based on the comparison result.

8 is a control flowchart of the audio device 1 according to the present invention. 8, the operation of the audio apparatus 1 according to the present invention will be described.

When the input signal to be outputted to the speaker is input, the modulator 110 modulates the input signal into the PWM signal so that the plurality of the switching units 120 are switched at least (S11). The plurality of switching units 120 are switched in response to a signal input from the modulator 110. A speaker is driven by an output signal output from the plurality of switching units 120 (S12). An output signal from the plurality of switching units 120, that is, an error correction signal, is input to the correction unit 100. The correction unit 100 compares the input error correction signal with the input signal, and corrects an error of an output signal, that is, an audio signal output to the speaker based on the comparison result (S13).

9 is a control flowchart of the audio device 1 according to an embodiment of the present invention. 9, the operation of the audio apparatus 1 according to an embodiment of the present invention will be described.

When the input signal to be outputted to the speaker is inputted, the modulator 110 modulates the input signal into the PWM signal so that the plurality of the switching units 120 are switched at least (S21). The plurality of switching units 120 are switched in response to a signal input from the modulator 110. The speakers are driven by the output signals output from the plurality of switching units 120 (S22). An output signal outputted from at least one of the output terminal between the plurality of switching units 120 and the filter unit 130 and the output terminal at the rear end of the filter unit 130 is inputted to the signal changing unit 140 (S23) . The signal input unit converts a plurality of output signals into an error correction signal and outputs the error correction signal to the correction unit (100). The correction unit 100 compares the input error correction signal with the input signal, and corrects an error of an output signal, that is, an audio signal output to the speaker based on the comparison result (S24).

Thus, although the switching efficiency is improved in the multilevel switching amplifier, it is difficult to ensure the audio performance due to no error correction. When the audio device 1 according to the present invention is used, the audio performance, which is a disadvantage of the multilevel switching amplifier, It is possible to constitute a switching amplifier system including the audio apparatus 1 effectively.

Further, even if the input signal and the output signal are not identical to each other by the audio apparatus 1 of the present invention, feedback of the output signal can be implemented to correct the nonlinear characteristics and errors of the audio apparatus 1.

While the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope or spirit of this invention. Accordingly, the scope of the invention is not to be determined by the embodiments described so far but on the basis of the appended claims and their equivalents.

1: Audio device
100:
110:
120:
130:
140: Signal change section
150: Power supply

Claims (10)

An audio device comprising:
A modulator for modulating an input signal;
A plurality of switching units for switching the speaker to correspond to the signal modulated by the modulator to drive the speaker;
And a correction unit that compares an error correction signal output from an output terminal of the plurality of switching units with the input signal and corrects an error of an output signal for driving the speaker based on the comparison result. The method according to claim 1,
And the speaker is located between the output terminals of the plurality of switching units. The method according to claim 1,
Further comprising a filter unit for filtering the switched signals from the plurality of switching units,
Wherein the correction unit compares the input signal with the error correction signal output from an output end of at least one of an output end between the plurality of switching units and the filter end and an output end of the rear end of the filter unit, And corrects an error of the output signal for driving the speaker. The method according to claim 1,
And a signal changing unit for changing a plurality of output signals output from the output terminals of the plurality of switching units to the error correction signal,
Wherein the correction section changes the plurality of output signals output from the output terminals of the plurality of switching sections by the signal changing section to the error correction signal and compares the changed error correction signal with the input signal, And corrects an error of the output signal for driving the speaker. The method according to claim 3 or 4,
Wherein the correction unit changes a plurality of output signals output from at least one output end of the output unit between the plurality of switching units and the filter unit and the output unit of the rear end of the filter unit by the signal changing unit to the error correction signal, Compares the changed error correction signal with the input signal, and corrects an error of the output signal for driving the speaker based on the comparison result. A method of controlling an audio device,
Modulating and outputting an input signal;
Driving the speaker by switching to correspond to the modulated signal;
And comparing the input signal with an error correction signal output from an output terminal of a plurality of switching units for switching to drive the speaker and correcting an error of an output signal for driving the speaker based on a result of the comparison Method of controlling an audio device. Wherein the speaker is located between the output terminals of the plurality of switching units. The method according to claim 6,
The step of correcting the error comprises:
For comparing the input signal with the error correction signal outputted from the output terminal of at least one of the output terminal between the plurality of switching units and the filter unit and the output terminal at the rear end of the filter unit, And correcting an error of the output signal. The method according to claim 6,
The step of correcting the error comprises:
A signal changing unit for changing a plurality of output signals output from the output terminals of the plurality of switching units to the error correction signal to compare the changed error correction signal with the input signal, And correcting an error of the output signal to correct an error of the output signal. 10. The method according to claim 8 or 9,
The step of correcting the error comprises:
A plurality of output signals output from at least one of an output end between the plurality of switching units and the filter unit and an output end of the rear end of the filter unit by the signal changing unit to the error correction signal, Comparing the signal with the input signal, and correcting an error of the output signal for driving the speaker based on the comparison result.
KR1020130010538A 2013-01-30 2013-01-30 Audio apparartus and control method thereof KR20140097874A (en)

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WO2017116149A1 (en) * 2015-12-28 2017-07-06 Samsung Electronics Co., Ltd. Control of electrodynamic speaker driver using a low-order non-linear model
US10462565B2 (en) 2017-01-04 2019-10-29 Samsung Electronics Co., Ltd. Displacement limiter for loudspeaker mechanical protection
US10506347B2 (en) 2018-01-17 2019-12-10 Samsung Electronics Co., Ltd. Nonlinear control of vented box or passive radiator loudspeaker systems
US10542361B1 (en) 2018-08-07 2020-01-21 Samsung Electronics Co., Ltd. Nonlinear control of loudspeaker systems with current source amplifier
US10701485B2 (en) 2018-03-08 2020-06-30 Samsung Electronics Co., Ltd. Energy limiter for loudspeaker protection
US10797666B2 (en) 2018-09-06 2020-10-06 Samsung Electronics Co., Ltd. Port velocity limiter for vented box loudspeakers
US11012773B2 (en) 2018-09-04 2021-05-18 Samsung Electronics Co., Ltd. Waveguide for smooth off-axis frequency response
US11356773B2 (en) 2020-10-30 2022-06-07 Samsung Electronics, Co., Ltd. Nonlinear control of a loudspeaker with a neural network

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Publication number Priority date Publication date Assignee Title
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US11356773B2 (en) 2020-10-30 2022-06-07 Samsung Electronics, Co., Ltd. Nonlinear control of a loudspeaker with a neural network

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