CN205490435U - Controllable supply voltage circuit for power amplifier - Google Patents
Controllable supply voltage circuit for power amplifier Download PDFInfo
- Publication number
- CN205490435U CN205490435U CN201620011488.2U CN201620011488U CN205490435U CN 205490435 U CN205490435 U CN 205490435U CN 201620011488 U CN201620011488 U CN 201620011488U CN 205490435 U CN205490435 U CN 205490435U
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- power
- circuit
- control circuit
- output stage
- amplifier
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Abstract
The utility model discloses a controllable supply voltage circuit for power amplifier, it contains a preamplification level, and be equipped with a preamplification ware and control circuit is strengthened to a bass of being connected with back coupling mode and this preamplification ware in this preamplification level, a power amplifier stage is equipped with an audio power output stage and a dynamic mains voltage change over switch in this power amplifier stage, this audio power output stage and preamplification level electric connection, and a less fixed mains voltage is connected to one of them input of these developments mains voltage change over switch, another input of dynamic mains voltage change over switch is connected to a supply voltage circuit for as preamplification level reinforcing bass audio signal the time, provide a dynamic mains voltage who is greater than this fixed power voltage to this power amplifier stage, therefore, the utility model discloses can realize the supper bass strengthening effect and dwindle the circuit size, keep the surplus and the dynamic of output simultaneously, and then reach the efficiency that improves the product practicality by a wide margin and reliably spend.
Description
Technical field
This utility model relates to a kind of power amplifier, and espespecially one has bass boost and dynamic power supplies
Control the audio-frequency power amplifier of (boomer and dynamic power range control) function.
Background technology
In audio-frequency power amplifier (Audio Power Amplifier) technical field, the most develop
Go out multiple circuit topology framework (topology), including: A class, B class, AB class, D class, G
Class etc., as a example by D audio frequency amplifier, as it is shown in figure 1, it has a comparison circuit 11, this ratio
Two inputs of relatively circuit 11 receive audio signal 111 and a triangular signal of a simulation respectively
112, thus a pulse-width modulation signal can be obtained at the outfan of comparison circuit 11, this PWM is believed
Number it is sent to a driving and output stage 12, in order to drive and to control this driving and the merit in output stage 12
Rate crystal, to obtain the pulse-width modulation signal after an amplification, finally, the PWM letter after this amplification
Number filter high frequency carrier through a low pass filter 13 again, the most reducible and obtain the audio frequency after this amplification
Signal is also exported by a speaker 2.
Existing audio-frequency power amplifier, though can realize amplify audio signal function, but still face with
Lower technical problem: firstly, for the most popular miniaturization acoustic product, the most portable indigo plant
Tooth loudspeaker, due to the restriction on volume of its horn single body, user often can only be in the facility carried
Property and the shock effect of audition between make choice, therefore, it is necessary to a kind of miniaturization of development and can be with
Time possess the audio frequency amplifier that supper bass is strengthened function；Secondly, along with the audio frequency of aforementioned bass strengthening
Amplifier and the problem come is: when the level of audio bass is dynamically increased, so that beyond power
During the supply voltage of output stage, by cause the audio output signal after amplifying by wave chopping (clipping),
Form saturation distortion phenomenon, cause loudspeaker that distorsion or sonic boom occur, have a strong impact on listening experience.So,
How to make audio-frequency power amplifier when strengthening bass level, supply voltage order can be dynamically adjusted simultaneously
It keeps enough surplus (headroom), to maintain enough out-put dynamic range (dynamic
Range), the technical task of a great urgency and practicality is become.
Utility model content
Because existing audio-frequency power amplifier is difficult to take into account miniaturization and strengthen supper bass effect simultaneously
Design object, therefore the purpose of this utility model be develop one can allow integrated circuit keep integrated
Change and can realize simultaneously the power amplifier device of bass boost effect.
Another object of the present utility model is when developing a kind of strengthening bass can realize dynamic power supplies simultaneously
Control the power amplifier device of (dynamic power range control) function.
In order to reach object above, this utility model provides a kind of power amplifier device, and it comprises:
One preamplifier state, is provided with a preamplifier and and in back coupling mode and is somebody's turn to do in this preamplifier state
The bass that preamplifier connects tightens control circuit, and this bass circuit that tightens control is provided with one first time
Award resistance and an active capacitance multiplier circuit in parallel with this first feedback resistance；One power amplification
Level, is provided with an audio power output stage and dynamic source voltage switching switch in this power-amplifier stage,
This audio power output stage is electrically connected with preamplifier state, and this dynamic source voltage switching switch has
One first power voltage input terminal, a second source voltage input end and a supply voltage outfan,
This first power voltage input terminal connect a less fixed power source voltage, this supply voltage outfan with
This audio power output stage is connected；One power supply circuit, is provided with amplitude in this power supply circuit
With detecting phase circuit, drive circuit and power output stage, this drive circuit includes reference
Voltage control circuit, error amplifier bandwidth control circuit and bleeder circuit, this error amplifier band
Wide control circuit has first input end, the second input and outfan, this amplitude and detecting phase
Circuit respectively with preamplifier state, reference voltage control circuit and error amplifier bandwidth control circuit
Second input be electrically connected with, this reference voltage control circuit also with error amplifier bandwidth control circuit
First input end be electrically connected with, the outfan of this error amplifier bandwidth control circuit and power supply merit again
The input of rate output stage is electrically connected with, and this bleeder circuit connects this power respectively in back coupling mode
The outfan of output stage and the second input of error amplifier bandwidth control circuit, this power again
The second source voltage input end that the outfan of output stage also switchs with dynamic source voltage switching electrically connects
Connect, in order to produce a dynamic source voltage bigger than fixed power source voltage.
In an embodiment of the present utility model, this preamplifier is full differential amplifier.
In an embodiment of the present utility model, this bass tightens control, and to be provided with one active with this for circuit
The second feedback resistance that capacitance multiplier circuit is in series, and the resistance value of this second feedback resistance is less than the
The resistance value of one feedback resistance.
In an embodiment of the present utility model, power amplifier device further includes a driving output
Level, this driving output stage is arranged between preamplifier state and power-amplifier stage, and this driving output stage
It is connected with preamplifier state and power-amplifier stage respectively.
In an embodiment of the present utility model, it is provided with in this driving output stage and controls electricity a dead time
Road and one with voltage position quasi displacement circuit that this, control circuit was electrically connected with dead time, during this stagnation
Between control circuit and voltage position quasi displacement circuit respectively with the preamplifier in preamplifier state and power
Message power output stage in amplifier stage is electrically connected with.
By said structure, this utility model can realize supper bass strengthening effect and reduce circuit size,
Keep surplus and the dynamic range of output simultaneously, and then reach product practicality and reliability are greatly improved.
Accompanying drawing explanation
Fig. 1 is the framework block schematic diagram of existing class-D amplifier；
Fig. 2 is framework block schematic diagram of the present utility model；
Fig. 3 is the schematic diagram of a kind of more specific embodiment of the preamplifier state in this utility model；
Fig. 4 is action schematic diagram of the present utility model.
Description of reference numerals: 11-comparison circuit；111-audio signal；112-triangular signal；12-
Drive and output stage；13-low pass filter；2-speaker；3-preamplifier state；31-preamplifier；
32-bass tightens control circuit；The active capacitance multiplier circuit of 321-；4-power-amplifier stage；41-audio frequency
Power output stage；42-dynamic source voltage switching switch；421-the first supply voltage outfan；422-
Second source voltage input end；423-supply voltage outfan；5-drives output stage；51-dead time
Control circuit；52-voltage position quasi displacement circuit；6-power supply circuit；61-amplitude and detecting phase electricity
Road；62-drive circuit；63-power output stage；631-input；632-outfan；64-joins
Examine voltage control circuit；65-error amplifier bandwidth control circuit；651-first input end；652-
Two inputs；653-outfan；66-bleeder circuit；7-speaker；Rf1-the first feedback resistance；Rf2-
Second feedback resistance；RIN-input resistance.
Detailed description of the invention
Following example are particularly applicable to the various existing merits such as A class, B class, AB class, D class
Rate amplifier, this is not limited by this utility model.
As in figure 2 it is shown, this utility model provides a kind of power amplifier device, it comprises:
One preamplifier state 3, is provided with a preamplifier 31 and to return in this preamplifier state 3
The bass that mode of awarding is connected with this preamplifier 31 tightens control circuit 32, as it is shown on figure 3, its
Disclosing this preamplifier state 3, the tighten control one of circuit 32 of bass the most therein is more specific
Embodiment, in this embodiment, this preamplifier 31 is preferably by having the complete of double output ends
Differential amplifier (fully differential amplifier), this kind of amplifier has preferably antinoise
Jamming effectiveness, it is adaptable to the application scenario that tonequality is had higher requirements, also the poorest because of have employed herein
Dynamic amplifier, so this bass tightens control, the quantity of circuit 32 is 2, more specifically, this bass
The circuit 32 that tightens control is provided with one first feedback resistance Rf1And one and this first feedback resistance Rf1In parallel
Active capacitance multiplier circuit 321, this kind of configuration can produce the effect of similar low pass filter, as
This, as long as suitably arranging the first feedback resistance Rf1Input resistance R with preamplifier 31INBetween
Ratio, this preamplifier 31 can be made to have bigger gain for the audio signal of low frequency, from
And realize the purpose of bass strengthening (bass boost), additionally, this bass tightens control, circuit 32 is also
A second feedback resistance R being in series with this active capacitance multiplier circuit 321 can be further provided withf2,
And this second feedback resistance Rf2Resistance value less than the first feedback resistance Rf1, the most also can reach identical
Bass strengthening effect, it addition, in the embodiment that other are feasible, this preamplifier 31 may be used without
Other kinds of amplifier, the such as differential amplifier of Single-end output (single ended output),
Now have only to use a bass tighten control circuit 32；
It should be noted that when selecting back coupling electric capacity for this preamplifier 31, in order to make front storing
Big device 31 has preferably LF-response characteristic, to realize real supper bass strengthening effect (with human ear
For the frequency range of the audio signal that can receive about 20～20kHz, typically at 50～250Hz models
The audio signal enclosing left and right just can be considered to be supper bass), it is often necessary to use sufficiently large electric capacity,
The electric capacity of such as nF grade, but the biggest electric capacity is difficult to be integrated in single with preamplifier 31
In IC chip, can only arrange with the form of discrete elements, thus the size of circuit board will be significantly increased,
Cannot meet the miniature requirement of portable acoustic product, to this, this utility model uses active electric
Hold the multiple circuit 321 back coupling electric capacity as this preamplifier 31, this active capacitance multiplier circuit
321 are actually a kind of active electric capacity containing active member (such as amplifier or transistor) times
Increasing device (active capacitance multiplier), it configures a less electric capacity in circuit, with
Time adjust, the ratio of different resistance in control circuit, thus whole circuit equivalent can be become one bigger
Electric capacity, the particular circuit configurations of this active capacitance multiplier circuit 321 is prior art, therefore at this not
Giving detailed description, thereby, this utility model only need to use reality in this active capacitance multiplier circuit 321
It is worth the electric capacity of only up to pF grade, gets final product equivalence and go out the effect of nF grade electric capacity, so that this practicality is new
Active capacitance multiplier circuit 321 can be integrated with preamplifier 31, be integrated in same IC by type
In chip, significantly to reduce the volume of circuit, and then make this utility model can reach bass strengthening simultaneously
And reduce effect of circuit size；
One power-amplifier stage 4, is provided with an audio power output stage 41, this sound in this power-amplifier stage 4
Frequently power output stage 41 is electrically connected with preamplifier state 3, in order to amplify via preamplifier state 3
The audio signal of output carries out power amplification, so that this power-amplifier stage 4 can be by after power amplification
Audio signal is sent to a speaker 7 and carries out audio frequency output, as power output stage, this sound
Frequently it is typically provided with power crystal in power output stage 41, using the transmitting element (pass as energy
Element), remaining concrete structure in this audio power output stage 41 is people in the art again
Member is known, repeats no more in this, additionally, also can be provided with a dynamic power supplies in this power-amplifier stage 4
Voltage changeover switch 42, this dynamic source voltage switching switch 42 has one first supply voltage input
End 421, one second source voltage input end 422 and a supply voltage outfan 423, wherein, should
First power voltage input terminal 421 connects a less fixed power source voltage, such as Vdd, this power supply
Voltage output end 423 is connected with this audio power output stage 41, in order to transmit the output of this audio power
Supply voltage needed for level 41；
The aforementioned set-up mode being directly connected to power-amplifier stage 4 after preamplifier state 3 is applicable to
The linear power amplifiers such as A class, B class, AB class, but, this utility model also can further include
Having a driving output stage 5, this driving output stage 5 is arranged on preamplifier state 3 and power-amplifier stage 4
Between, and this driving output stage 5 is connected with preamplifier state 3 and power-amplifier stage 4 respectively, should
It is provided with in driving output stage 5 and controls (dead time control) circuit 51 and a dead time
(level shift) circuit 52 is shifted with the voltage level that this dead time, control circuit 51 was electrically connected with,
This dead time control circuit 51 and voltage position quasi displacement circuit 52 respectively with in preamplifier state 3
Audio power output stage 41 in preamplifier 31 and power-amplifier stage 4 is electrically connected with, and this moves again
State supply voltage switching switch 42 in supply voltage outfan 423 also with this voltage position quasi displacement circuit
52 are connected, in order to transmit the supply voltage needed for this voltage position quasi displacement circuit 52, wherein, and should
Dead time, control circuit 51 was in order to avoid the high side (high side) in audio power output stage 41
And the power crystal of downside (low side) simultaneously turns on and causes power supply short circuit, thus this voltage level moves
Position circuit 52 is in order to promote the voltage level of audio signal, successfully to drive the power crystal of high side,
Thereby, this utility model is equally applicable to the power amplifier of this switch type of class-D amplifier,
Further, if being reconfigured at one for switching enable (enabled) state of this driving output stage 5
Control circuit, then this utility model can further apply and be mixed with linear power amplifier and switch is cut
Remodel in the power amplifier circuit framework of power amplifier, and then can be greatly improved of the present utility model
Range of application and wide usage；
One power supply circuit 6, this power supply circuit 6 is specially a kind of self adaptation booster type power supply
Transducer (adaptive boost power converter), in order to strengthen low when preamplifier state 3
During sound audio signal, this power-amplifier stage 4 is provided a dynamic power supplies being more than this fixed power source voltage
Voltage, so that the supply voltage of power-amplifier stage 4 can keep certain surplus (headroom),
With the out-put dynamic range that maintenance is enough, in the present embodiment, it is provided with in this power supply circuit 6 and shakes
Width and detecting phase circuit 61, drive circuit 62 and power output stage 63, wherein, this drives
Galvanic electricity road 62 include reference voltage control circuit 64, error amplifier bandwidth control circuit 65 and
Bleeder circuit 66, this error amplifier bandwidth control circuit 65 is generally by error amplifier (Error
Amplifier) and necessity back coupling compensate circuit constitute, this back coupling compensate circuit typically by electric capacity,
The element compositions such as resistance, in order to regulate and control the bandwidth (Bandwidth) of this error amplifier, transient response
The characteristics such as (transient response) and stability, so that error amplifier can be to load change
Obtaining between response speed and the stability of system and preferably balance, this error amplifier bandwidth controls electricity
Road 65 has first input end the 651, second input 652 and outfan 653, this amplitude and phase
Position circuit for detecting 61 tightens control with the bass in preamplifier state 3 circuit 32, reference voltage respectively
Second input 652 of control circuit 64 and error amplifier bandwidth control circuit 65 is electrically connected with,
This reference voltage control circuit 64 also with the first input end of error amplifier bandwidth control circuit 65
651 are electrically connected with, again the outfan 653 of this error amplifier bandwidth control circuit 65 and power
The input 631 of output stage 63 is electrically connected with, and this bleeder circuit 66 connects this respectively in back coupling mode
The outfan 632 of power output stage 63 is defeated with the second of error amplifier bandwidth control circuit 65
Entering end 652, the outfan 632 of this power output stage 63 also leaves with dynamic source voltage switching again
The second source voltage input end 422 of pass 42 is electrically connected with；
Wherein, after this amplitude and detecting phase circuit 61 are in order to detect via preamplifier state 3 amplification
The amplitude (amplitude) of audio signal and phase place (phase), and by the amplitude signal that detects with
And phase signal is respectively transmitted and controls electricity to reference voltage control circuit 64 and error amplifier bandwidth
Road 65, this reference voltage control circuit 64 can produce the reference electricity of a correspondence according to this amplitude signal
Pressure (Reference Voltage, VREF) signal, then this reference voltage signal is sent to this error puts
The first input end 651 of big device bandwidth control circuit 65, this error amplifier bandwidth control circuit 65
Internal back coupling compensates circuit can produce and determine the bandwidth of this error amplifier according to this phase signal
With transient response characteristic, the outfan 653 of this error amplifier bandwidth control circuit 65 can be according to input
The signal of end produces the pulse-width control signal of a correspondence and is sent to power output stage 63, thus can
Outfan 632 in this power output stage 63 produces this dynamic source voltage and sends dynamic electric to
Source voltage changeover switch 42；
Operation principle of the present utility model and beneficial effect are described below: as shown in Figure 3 and Figure 4, when
When audio signal belongs to middle pitch or treble range, the gain that this preamplifier state 3 produces is less, thus
Message power output stage 41 in power-amplifier stage 4 can without bigger supply voltage, so time dynamic
Supply voltage switching switch 42 can switch its on off state, utilizes and the first power voltage input terminal 421
Audio power output stage 41 is powered by the fixed power source voltage being connected with voltage position quasi displacement circuit 52；
When audio signal belongs to bass or supper bass scope, this bass circuit 32 that tightens control can make front storing
Big level 3 produces bigger gain, the now amplitude in this power supply circuit 6 and detecting phase circuit
61 can detect bigger amplitude signal, thus this reference voltage control circuit 64 can to produce one bigger
Reference voltage signal, thus dynamically make power output stage 63 produce relatively fixed power source voltage
Big dynamic source voltage, now, this dynamic source voltage switching switch 42 can switch its switch shape again
State, makes the dynamic source voltage being connected with second source voltage input end 422 to audio power output stage
41 power with voltage position quasi displacement circuit 52, consequently, it is possible to when preamplifier state 3 strengthens bass
Audio signal and when improving its level, this power supply circuit 6 can synchronize and dynamically by audio frequency
The supply voltage of power output stage 41 rises to higher level, thus the power level that order is now can be protected
Hold the audio signal level more than bass, it is to avoid the saturation distortion that audio output signal is caused by wave chopping,
Thus realize dynamic power supplies and control function, and then make this utility model can reach properties of product are substantially improved
Effect with reliability.
Claims (5)
1. a power amplifier device, it is characterised in that comprise:
One preamplifier state, is provided with a preamplifier and in back coupling mode in this preamplifier state
The bass being connected with this preamplifier tightens control circuit, and this bass circuit that tightens control is provided with one
One feedback resistance and an active capacitance multiplier circuit in parallel with this first feedback resistance；
One power-amplifier stage, is provided with an audio power output stage and a dynamic electric in this power-amplifier stage
Source voltage changeover switch, this audio power output stage is electrically connected with preamplifier state, this dynamic power supplies
Voltage changeover switch has one first power voltage input terminal, a second source voltage input end and
Supply voltage outfan, this first power voltage input terminal connects a less fixed power source voltage, should
Supply voltage outfan is connected with this audio power output stage；
One power supply circuit, is provided with amplitude and detecting phase circuit, driving in this power supply circuit
Circuit and power output stage, this drive circuit includes reference voltage control circuit, error is put
Big device bandwidth control circuit and bleeder circuit, it is defeated that this error amplifier bandwidth control circuit has first
Enter end, the second input and outfan, this amplitude and detecting phase circuit respectively with preamplifier state,
Second input of reference voltage control circuit and error amplifier bandwidth control circuit is electrically connected with, should
Reference voltage control circuit is also electrically connected with the first input end of error amplifier bandwidth control circuit,
The outfan of this error amplifier bandwidth control circuit electrically connects with the input of power output stage again
Connecing, the outfan that this bleeder circuit connects this power output stage respectively in back coupling mode is put with error
Second input of big device bandwidth control circuit, again the outfan of this power output stage also with dynamically
The second source voltage input end of supply voltage switching switch is electrically connected with, in order to produce one than fixing electricity
The dynamic source voltage that source voltage is big.
Power amplifier device the most according to claim 1, it is characterised in that this preamplifier
For full differential amplifier.
Power amplifier device the most according to claim 1, it is characterised in that this bass strengthens control
Circuit processed is provided with second feedback resistance being in series with this active capacitance multiplier circuit, and this second
The resistance value of feedback resistance is less than the resistance value of the first feedback resistance.
Power amplifier device the most according to any one of claim 1 to 3, it is characterised in that
Further includeing a driving output stage, this driving output stage is arranged at preamplifier state and power amplification
Between Ji, and this driving output stage is connected with preamplifier state and power-amplifier stage respectively.
Power amplifier device the most according to claim 4, it is characterised in that this driving output stage
Inside be provided with one dead time control circuit and one with voltage that this, control circuit was electrically connected with dead time
Position quasi displacement circuit, this dead time control circuit and voltage position quasi displacement circuit respectively with preposition amplification
Preamplifier in Ji and the audio power output stage in power-amplifier stage are electrically connected with.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620011488.2U CN205490435U (en) | 2016-01-06 | 2016-01-06 | Controllable supply voltage circuit for power amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620011488.2U CN205490435U (en) | 2016-01-06 | 2016-01-06 | Controllable supply voltage circuit for power amplifier |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205490435U true CN205490435U (en) | 2016-08-17 |
Family
ID=56664091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620011488.2U Withdrawn - After Issue CN205490435U (en) | 2016-01-06 | 2016-01-06 | Controllable supply voltage circuit for power amplifier |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN205490435U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106953608A (en) * | 2016-01-06 | 2017-07-14 | 昱盛电子股份有限公司 | Power amplifier device |
-
2016
- 2016-01-06 CN CN201620011488.2U patent/CN205490435U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106953608A (en) * | 2016-01-06 | 2017-07-14 | 昱盛电子股份有限公司 | Power amplifier device |
| CN106953608B (en) * | 2016-01-06 | 2019-05-21 | 昱盛电子股份有限公司 | Power amplifier device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20160817 Effective date of abandoning: 20190521 |
|
| AV01 | Patent right actively abandoned |