CN203675057U - Audio power amplifier of integrated boosted circuit - Google Patents
Audio power amplifier of integrated boosted circuit Download PDFInfo
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- CN203675057U CN203675057U CN201320542651.4U CN201320542651U CN203675057U CN 203675057 U CN203675057 U CN 203675057U CN 201320542651 U CN201320542651 U CN 201320542651U CN 203675057 U CN203675057 U CN 203675057U
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Abstract
The utility model relates to an amplifier, and discloses an audio power amplifier of an integrated boosted circuit. The audio power amplifier comprises an internal power source managing module providing constant power, a power amplification selection module, a D-type audio power amplifier, an AB-type audio power amplifier and an output module. Battery voltage Vin is input in the input end of the internal power source managing module, the Vin is subjected to boosting conversion, and constant voltage VRG is output and controlled by mode signals of the power amplification selection module. According to the type of audio signals, power voltages matched with the D-type audio power amplifier and the AB-type audio power amplifier are selected to be output. The internal power source managing module can be used for providing constant power for the audio power amplifiers, so that the phenomenon that output power of the D-type audio power amplifier and the AB-type audio power amplifier change along with changes of the battery voltage is avoided, the problems that output clipping occurs due to reduction of the battery voltage and tone quality becomes poor are solved, and stability voltage is provided for an external device.
Description
Technical field
The utility model relates to audio-frequency power amplifier, particularly the audio-frequency power amplifier of integrated boost circuit.
Background technology
In Mobile audio frequency equipment, D genus audio power amplifier (referring to digital power amplifier) is because efficiency is high, and required area of dissipation is little, saves the advantages such as layout and is widely used.Fig. 1 is the schematic diagram that traditional use D class audio frequency power amplifier drives loud speaker.D class power amplifier is by high-frequency PWM (Pulse Width Modulation pulse width modulation) ripple, audio signal to be modulated, and adopts switching device to drive external loudspeaker.Owing to adopting switching technique, output is digital signal, and as shown in Figure 2, numbering 21 represents high-frequency modulation signal, and numbering 22 represents high-frequency switching signal.Generally can produce the EMI(Electro Magnetic Interference electromagnetic interference of three aspects :) high-frequency noise:
Output square wave itself upper and lower along time high-frequency signal;
2. dead band (the triode of the upper and lower bridge arm of PWM conducting simultaneously.If conducting simultaneously will make both ends of power short circuit, so two-way triggering signal will all make triode disconnect within a period of time.This region is just called " dead band ") time power tube Mn(Fig. 2 in 23), the spike energy of the parasitic diode of Mp (in Fig. 2 24) when opening and oppositely recovering (parasitic diode is more short better reverse recovery time);
Output square wave upper and lower when switching by PCB(PrintedCircuitBoard, printed circuit board) parasitic capacitance and the caused ring energy of inductance on line.These high-frequency noises can destroy FM(Frequency Modulation, frequency modulation) input signal of receiver end, cause FM receiver cannot normally differentiate broadcast singal.
Due to the existence of above-mentioned high frequency E MI noise, badly influence FM frequency modulation.
AB class (class AB complementary push-pull) audio-frequency power amplifier is analog signal because of output, can not produce EMI noise, but efficiency is not high.
A kind of technical scheme is that D class, AB power-like amplifier are integrated in a chip, as shown in Figure 3, select automatically as required suitable audio-frequency power amplifier: in the time playing music, select D power-like amplifier, in the time of FM frequency modulation, select AB power-like amplifier, as shown in Figure 4.
Although this technical scheme can solve FM noise jamming problem, but in mobile device, because this audio frequency apparatus is directly connected on battery conventionally, tonequality, power etc. are limited to cell voltage, when cell voltage decline can cause exporting slicing, both poor sound quality, power output declines, and especially, for 4 ohm or the loud speaker of high impedance more, power output is little.
Utility model content
The purpose of this utility model is to provide a kind of audio-frequency power amplifier of integrated boost circuit, make this audio-frequency power amplifier can avoid the power output of audio-frequency power amplifier to change with the variation of cell voltage, and the output slicing causing due to the decline of cell voltage, the problem of both poor sound quality.
For solving the problems of the technologies described above, the utility model provides a kind of audio-frequency power amplifier of integrated boost circuit, comprises the built-in power of stabilized power source administration module is provided, power amplifier is selected module, D genus audio power amplifier, AB genus audio power amplifier, output module;
The input input cell voltage Vin of described built-in power administration module, output is connected with the input of described AB genus audio power amplifier side by side with described D genus audio power amplifier;
Described power amplifier selects module to be connected with described built-in power administration module, controls the supply voltage that described built-in power administration module output and described D genus audio power amplifier or described AB genus audio power amplifier match;
Described D genus audio power amplifier is connected with the output of described AB genus audio power amplifier and the input of described output module;
The output output audio signal of described output module.
In terms of existing technologies, utilize Switching Boost Converter Used that above-mentioned built-in power administration module provides to provide constant power supply for audio-frequency power amplifier, so just can avoid D class, the power output of AB genus audio power amplifier changes with the variation of cell voltage, and the output slicing causing because of the decline of cell voltage, the problem of both poor sound quality, there is good PSRR(Power Supply Rejection Ratio, Power Supply Rejection Ratio: supply voltage is regarded as to independently signal source, the ratio of power supply ripple and output ripple be PSRR), above-mentioned built-in power module also can provide stable voltage for external devices simultaneously.
As further improvement of the utility model, above-mentioned built-in power administration module also comprises Switching Boost Converter Used and power selection switch;
The input input cell voltage of described Switching Boost Converter Used, output is connected with the input of described power selection switch;
The output of described power selection switch is connected with the input of described AB genus audio power amplifier side by side with described D genus audio power amplifier;
Described power selection switch receives the control signal that described power amplifier selects module to export, the supply voltage that described power selection switch matches according to described control signal output and described D genus audio power amplifier or described AB genus audio power amplifier.
Above-mentioned power selection switch can be selected according to described power amplifier the mode signal of the control signal of module selection, the selectively cell voltage of output after above-mentioned Switching Boost Converter Used boosts, and match with corresponding audio-frequency power amplifier.
In addition, cell voltage Vin is carried out boost conversion by above-mentioned Switching Boost Converter Used, exports constant voltage VRG.
Switching Boost Converter Used can carry out boost conversion by the cell voltage Vin of input, export constant voltage VRG, this constant voltage VRG just can provide constant voltage for the work of D genus audio power amplifier or described AB genus audio power amplifier, so just can avoid the power output of D class, AB genus audio power amplifier to change with the variation of cell voltage, and the output slicing causing because of the decline of cell voltage, the problem of both poor sound quality.
In addition, the asynchronous boost switching circuit that the circuit of above-mentioned Switching Boost Converter Used is current-mode.
Because booster circuit need to provide power supply to audio-frequency power amplifier, and audio-frequency power amplifier is the in the situation that of high-power output, need power supply that enough large electric current can be provided, so Switching Boost Converter Used adopts asynchronous structure, in booster circuit, power tube just only has the more intense nmos(N Metal Oxide Semiconductor of current capacity like this, N channel metal oxide semiconductor transistor) pipe, the while also can be saved the area of chip.
In addition, above-mentioned asynchronous boost switching circuit comprises current loop and voltage loop, and wherein current loop is interior ring, and voltage loop is outer shroud.
By the Switching Boost Converter Used that cooperatively interacts and just can obtain needing in the utility model of above-mentioned two loops, and then provide supply voltage by this Switching Boost Converter Used for the normal work of described D genus audio power amplifier or AB genus audio power amplifier.
In addition, described power amplifier selects module by described built-in power administration module output low level or high level, controls the supply voltage that described built-in power administration module output and described D genus audio power amplifier or described AB genus audio power amplifier match.
When described power amplifier is selected module to described built-in power administration module output low level, described AB genus audio power amplifier is in running order;
When described power amplifier is selected module to described built-in power administration module output high level, described D genus audio power amplifier is in running order.
This relation one to one can better make the work of two power-like amplifiers do not affected each other, both can solve FM noise jamming problem, can improve again the operating efficiency of audio frequency apparatus.
In addition, the built-in power administration module of the stabilized power source in the utility model, D genus audio power amplifier and AB genus audio power amplifier are produced on single chips, can saving chip area, reduce whole device periphery resistance capacitance number, and reduce costs.
In addition, the built-in power administration module of the stabilized power source in the utility model, D genus audio power amplifier and AB genus audio power amplifier also can be produced on three chips, can make like this configuration of whole device more flexible.
Accompanying drawing explanation
Fig. 1 is the D class audio frequency power amplifier schematic diagram of reactive filter in prior art;
Fig. 2 is D class audio frequency power amplifier output schematic diagram in prior art;
Fig. 3 is D class and AB class combining audio system schematic in prior art;
Fig. 4 is combining audio system selection mode schematic diagram in prior art;
Fig. 5 is according to the audio-frequency power amplifier schematic diagram of a kind of integrated boost circuit in the utility model;
Fig. 6 is the asynchronous boost switching circuit diagram according to current-mode in the utility model;
Fig. 7 is the control signal pattern diagram of selecting module output according to power amplifier in the utility model.
Embodiment
For making the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with accompanying drawing, each execution mode of the present utility model is explained in detail.But, persons of ordinary skill in the art may appreciate that in the each execution mode of the utility model, in order to make reader understand the application better, many ins and outs are proposed.But, even without these ins and outs and the many variations based on following execution mode and modification, also can realize the each claim of the application technical scheme required for protection.
The first execution mode of the present utility model relates to a kind of audio-frequency power amplifier of integrated boost circuit.Comprise the built-in power of stabilized power source administration module is provided, power amplifier is selected module, D genus audio power amplifier (mainly referring to digital power amplifier), AB class (class AB complementary push-pull) audio-frequency power amplifier, output module.Wherein built-in power administration module comprises Switching Boost Converter Used and power selection switch, the input input cell voltage Vin of Switching Boost Converter Used, output is connected with the input of power selection switch, and the output of power selection switch is connected with the input of AB genus audio power amplifier side by side with D genus audio power amplifier, power amplifier selects module to be connected with built-in power administration module, according to the pattern of the type selecting control signal of audio signal, power selection switch receives the mode signal of the control signal of power amplifier selection module selection, the supply voltage of selecting output and D genus audio power amplifier or AB genus audio power amplifier to match, D genus audio power amplifier is connected with the output of AB genus audio power amplifier and the input of output module, output module output audio signal drives outside loud speaker, wherein said audio signal can be digital audio and video signals, also can be simulated audio signal.Specifically, as shown in Figure 5:
Built-in power administration module 51 is made up of Switching Boost Converter Used 52 and power selection switch 53, the input input cell voltage Vin(of Switching Boost Converter Used 52 is generally 2.7V～4.2V), and Vin is carried out to boost conversion, export constant voltage VRG to power selection switch 53, power selection switch 53 is subject to power amplifier to select the mode signal MODE of the control signal selected of module 54 to control, according to the type of audio signal, select the supply voltage V_D that output matches with D genus audio power amplifier 55 respectively or the supply voltage V_AB matching with AB genus audio power amplifier 56, when chip operation, there are two kinds of operating states, if in FM frequency modulation state, what audio-frequency power amplifier need to amplify is broadcast voice signal, power amplifier is selected the control signal of module 54 to power selection switch 53 output low level patterns, power selection switch 53 is output as V_AB, now D genus audio power amplifier 55 is not worked, AB genus audio power amplifier 56 is worked, the audio signal Audio_AB of output drives outside loud speaker output audio signal Audio_AB through output 57, if broadcasting music, export the control signal of high level mode to power selection switch 53, power selection switch 53 is output as V_D, now AB genus audio power amplifier 56 is not worked, D genus audio power amplifier 55 is worked, and the audio signal Audio_D of output drives outside loud speaker output audio signal Audio_D through output 57.
In terms of existing technologies, utilize the Switching Boost Converter Used 52 that above-mentioned built-in power administration module 51 provides that the cell voltage Vin of input is carried out to boost conversion, export constant voltage VRG, this constant voltage VRG just can provide constant voltage for the work of D genus audio power amplifier 55 or described AB genus audio power amplifier 56, so just can avoid D class, the power output of AB genus audio power amplifier changes with the variation of cell voltage, and the output slicing causing because of the decline of cell voltage, the problem of both poor sound quality, there is good PSRR(Power Supply Rejection Ratio, Power Supply Rejection Ratio: supply voltage is regarded as to independently signal source, the ratio of power supply ripple and output ripple be PSRR), above-mentioned built-in power module 51 also can provide stable voltage for external devices simultaneously
Wherein, the asynchronous boost switching circuit that above-mentioned Switching Boost Converter Used 52 is current-mode, as shown in Figure 6.There are two loops the inside, is respectively current loop 61 and voltage loop 62, and current loop 61 is interior rings, and voltage loop 62 is outer shrouds.62 li of voltage loops, resistance R 1 and resistance R 2 form feedback circuit, VRG obtains feedback voltage Vfb by R1 and R2 dividing potential drop, the difference that amplifier EA amplifies Vfb and reference voltage Vref obtains signal voltage Vea, the signal that Vea returns through the compensating network of resistance R z and capacitor C z formation with from inductance L 1 sampling compares, obtain digital switch signal, this digital switch signal is again through overdrive circuit N driving power pipe M1.The Switching Boost Converter Used voltage that just can be obtained needing in the utility model by cooperatively interacting of above-mentioned voltage loop 62 and current loop 61, and then be described D genus audio power amplifier 55 or the normal work raising supply voltage of AB genus audio power amplifier 56 by this Switching Boost Converter Used voltage.
According to the principle of Switching Boost Converter Used, between VRG and Vin, meet formula below:
Wherein D is duty ratio, is automatically regulated by feedback control loop.VRG is by the resistance R 1 in feedback circuit, and R2 and reference voltage Vref determine, the relation between them is as follows:
Because above-mentioned boost switching circuit need to provide power supply to audio-frequency power amplifier, and audio-frequency power amplifier is the in the situation that of high-power output, need power supply that enough large electric current can be provided, so this Switching Boost Converter Used 52 adopts asynchronous structure, power tube in boost switching circuit just only has the more intense nmos(N Metal Oxide Semiconductor of current capacity like this, N-type MOS (metal-oxide-semiconductor) transistor) pipe, such words also can be saved the area of chip.
Above-mentioned formula has disclosed relation between VRG and Vin and the rule of definite VRG.The mode signal of the control signal that after being convenient to, power selection switch 53 is selected according to above-mentioned power amplifier selection module 54, the supply voltage that output and D genus audio power amplifier 55 or AB genus audio power amplifier 56 match.
The mode signal of the control signal that above-mentioned power selection switch 53 can be selected according to described power amplifier selection module 54 in addition, the selectively cell voltage of output after above-mentioned Switching Boost Converter Used 53 boosts, and match with corresponding audio-frequency power amplifier.
In addition the control signal pattern MODE that above-mentioned power amplifier selection module 54 is exported as shown in Figure 7, if when the control signal MODE that power amplifier selects module 54 to export is low level mode, represent it is at this moment AB class mode of operation, power supply does not need to boost, the boost switching circuit of built-in power administration module 51 inside does not need work, as numbered 71 in Fig. 7; In the time that power amplifier selects the control signal pattern MODE that exports of module 54 to switch to high level mode, boost switching circuit is started working, and VRG rising, to setting voltage, is at this moment D class mode of operation, as numbered 72 in Fig. 7.This relation one to one can better make the work of two power-like amplifiers do not affected each other, both can solve FM noise jamming problem, can improve again the operating efficiency of audio frequency apparatus.
Built-in power administration module 51, D genus audio power amplifier 55 and the AB genus audio power amplifier 56 of the stabilized power source in the utility model are produced on single chips, like this can saving chip area, reduce whole device periphery resistance capacitance number, reduce costs.
In addition, the built-in power administration module 51 of the stabilized power source in the utility model, D genus audio power amplifier 55 and AB genus audio power amplifier 56 also can be produced on three chips, can make like this configuration of whole device more flexible.
Persons of ordinary skill in the art may appreciate that the respective embodiments described above are to realize specific embodiment of the utility model, and in actual applications, can do various changes to it in the form and details, and do not depart from spirit and scope of the present utility model.
Claims (8)
1. an audio-frequency power amplifier for integrated boost circuit, is characterized in that, comprises the built-in power of stabilized power source administration module is provided, and power amplifier is selected module, D genus audio power amplifier, AB genus audio power amplifier, output module;
The input input cell voltage Vin of described built-in power administration module, output is connected with the input of described AB genus audio power amplifier side by side with described D genus audio power amplifier;
Described power amplifier selects module to be connected with described built-in power administration module, controls the supply voltage that described built-in power administration module output and described D genus audio power amplifier or described AB genus audio power amplifier match;
Described D genus audio power amplifier is connected with the output of described AB genus audio power amplifier and the input of described output module;
The output output audio signal of described output module.
2. the audio-frequency power amplifier of integrated boost circuit according to claim 1, is characterized in that, described built-in power administration module comprises Switching Boost Converter Used and power selection switch;
The input input cell voltage of described Switching Boost Converter Used, output is connected with the input of described power selection switch;
The output of described power selection switch is connected with the input of described AB genus audio power amplifier side by side with described D genus audio power amplifier;
Described power selection switch receives the control signal that described power amplifier selects module to export, the supply voltage that described power selection switch matches according to described control signal output and described D genus audio power amplifier or described AB genus audio power amplifier.
3. the audio-frequency power amplifier of integrated boost circuit according to claim 2, is characterized in that, the asynchronous boost switching circuit that the circuit of described Switching Boost Converter Used is current-mode.
4. the audio-frequency power amplifier of integrated boost circuit according to claim 3, is characterized in that, described asynchronous boost switching circuit comprises current loop and voltage loop, and wherein current loop is interior ring, and voltage loop is outer shroud.
5. the audio-frequency power amplifier of integrated boost circuit according to claim 1, is characterized in that, described cell voltage is 2.7V～4.2V.
6. the audio-frequency power amplifier of integrated boost circuit according to claim 1, it is characterized in that, described power amplifier selects module by described built-in power administration module output low level or high level, controls the supply voltage that described built-in power administration module output and described D genus audio power amplifier or described AB genus audio power amplifier match.
7. according to the audio-frequency power amplifier of the integrated boost circuit described in any one in claim 1 to 6, it is characterized in that, described in provide built-in power administration module, D genus audio power amplifier and the AB genus audio power amplifier of stabilized power source to be produced on single chips.
8. according to the audio-frequency power amplifier of the integrated boost circuit described in any one in claim 1 to 6, it is characterized in that, described in provide built-in power administration module, D genus audio power amplifier and the AB genus audio power amplifier of stabilized power source to be produced on three chips.
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| CN201320542651.4U CN203675057U (en) | 2013-09-02 | 2013-09-02 | Audio power amplifier of integrated boosted circuit |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107360505A (en) * | 2017-07-10 | 2017-11-17 | 深圳市中移联半导体科技有限公司 | A kind of high-effect automatic modulation booster circuit and control method |
| CN110504925A (en) * | 2019-08-02 | 2019-11-26 | 武汉谐声半导体科技有限公司 | The D-type power amplifier and system of dynamically boosted control output |
| CN110582935A (en) * | 2017-04-07 | 2019-12-17 | 思睿逻辑国际半导体有限公司 | Switching in an audio system having multiple playback paths |
| CN112653400A (en) * | 2020-12-10 | 2021-04-13 | Oppo（重庆）智能科技有限公司 | Amplifying circuit, control method thereof, electronic device, and storage medium |
| CN115037257A (en) * | 2022-08-11 | 2022-09-09 | 上海芯龙半导体技术股份有限公司南京分公司 | Audio power amplifying circuit and audio power amplifying chip |
| CN116232258A (en) * | 2023-02-27 | 2023-06-06 | 重庆见芒信息技术咨询服务有限公司 | Dual-power amplifier switching method and system |
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2013
- 2013-09-02 CN CN201320542651.4U patent/CN203675057U/en not_active Expired - Lifetime
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110582935A (en) * | 2017-04-07 | 2019-12-17 | 思睿逻辑国际半导体有限公司 | Switching in an audio system having multiple playback paths |
| CN110582935B (en) * | 2017-04-07 | 2021-08-24 | 思睿逻辑国际半导体有限公司 | Switching in an audio system having multiple playback paths |
| CN107360505A (en) * | 2017-07-10 | 2017-11-17 | 深圳市中移联半导体科技有限公司 | A kind of high-effect automatic modulation booster circuit and control method |
| WO2019010967A1 (en) * | 2017-07-10 | 2019-01-17 | 深圳市中移联半导体科技有限公司 | High efficiency automatic modulation voltage boost circuit and control method |
| CN107360505B (en) * | 2017-07-10 | 2021-06-08 | 林其亮 | High-efficiency automatic modulation booster circuit and control method |
| CN110504925A (en) * | 2019-08-02 | 2019-11-26 | 武汉谐声半导体科技有限公司 | The D-type power amplifier and system of dynamically boosted control output |
| CN110504925B (en) * | 2019-08-02 | 2023-08-15 | 苏州至盛半导体科技有限公司 | Class D power amplifier and system with dynamic boost control output |
| CN112653400A (en) * | 2020-12-10 | 2021-04-13 | Oppo（重庆）智能科技有限公司 | Amplifying circuit, control method thereof, electronic device, and storage medium |
| CN115037257A (en) * | 2022-08-11 | 2022-09-09 | 上海芯龙半导体技术股份有限公司南京分公司 | Audio power amplifying circuit and audio power amplifying chip |
| CN115037257B (en) * | 2022-08-11 | 2022-12-27 | 上海芯龙半导体技术股份有限公司南京分公司 | Audio power amplifying circuit and audio power amplifying chip |
| CN116232258A (en) * | 2023-02-27 | 2023-06-06 | 重庆见芒信息技术咨询服务有限公司 | Dual-power amplifier switching method and system |
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Granted publication date: 20140625 |