CN106411280A - Power limitation amplifier - Google Patents
Power limitation amplifier Download PDFInfo
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- CN106411280A CN106411280A CN201510450173.8A CN201510450173A CN106411280A CN 106411280 A CN106411280 A CN 106411280A CN 201510450173 A CN201510450173 A CN 201510450173A CN 106411280 A CN106411280 A CN 106411280A
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- transistor
- voltage value
- operational amplifier
- resistance
- preset voltage
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Abstract
A power limitation amplifier comprises an operational amplifier, a gain reduction unit, a detection unit, a first resistor and a second resistor. The operational amplifier comprises a first input end, a second input end and an output end, the second resistor is coupled between the first input end and the output end of the operational amplifier, and the gain reduction unit is coupled between the first resistor and the first input end of the operational amplifier. A comparison unit is used to compare at least one output signal generated by the operational amplifier and at least one preset voltage value to generate at least one control signal, and a first gain reduction unit changes the resistance value according to the at least one control signal.
Description
Technical field
The present invention is with regard to a kind of Power Limitation amplifier.
Background technology
Audio frequency amplifier is a kind of power amplifier for amplifying audio signal.Conventional audio amplifier can
It is categorized as A class, B class, AB class and class-D amplifier, wherein class-D amplifier is due to having high efficiency
And the advantage of low-power consumption, become the main flow of audio-frequency power amplifier in recent years.Fig. 1 shows known to one
The block chart of class-D amplifier.As shown in figure 1, this class-D amplifier 100 comprises two input capacitances C1
With C2, a gain amplification stage 12, a pulse width modulator 13, two feedback networks 14 and 15 and two work(
Rate level 16 and 18.
With reference to Fig. 1, this input capacitance C1 and C2 in order to filter the Dc bias of an audio input signal, with
Produce signal AI1 and signal AI2.This gain amplification stage 12 to amplify signal by the ratio of resistance R1 to R4
AI1 and the voltage difference of signal AI2, to produce signal AG1 and signal AG2.This pulse width modulator 13 exists
Receive simulation pattern signal AG1 and signal AG2 after, output two pulse-width signal PWMP and
PWMN is to power stage 16 and 18.This pulse width modulator 13 generally comprises an integrator (not drawing) to integrate
Analogue signal AG1 and the voltage difference of signal AG2.These pulse-width signals PWMP and PWMN
Can produce by feedback network 14 and 15 and feed back signal to this pulse width modulator 13.These power stages 16 and 18
In order to promote a load circuit 19, the such as audio output device such as one earphone or loudspeaker.
In application, when the amplitude of audio input signal is excessive, this class-D amplifier 100 may need one
Circuit to limit output in a particular range, so as to avoiding load circuit 19 is caused damage.
Content of the invention
The present invention provides a kind of Power Limitation amplifier, comprises an operational amplifier, one first fall gain list
Unit, a detector unit, a first resistor and a second resistance.It is defeated that this operational amplifier comprises one first
Enter end, one second input and one first outfan.This second resistance is coupled to being somebody's turn to do of this operational amplifier
Between this first outfan of first input end and this operational amplifier.This first fall gain unit is coupled to
Between this first input end of this first resistor and this operational amplifier.This comparing unit is in order to compare generation
In at least one output signal and at least one preset voltage value of this operational amplifier, so as to producing at least one control
Signal processed.This first fall gain unit is according to this at least one control signal to change its resistance.
Brief description
Fig. 1 shows the block chart of class-D amplifier known to.
Fig. 2 shows the block schematic diagram of the Power Limitation amplifier combining one embodiment of the invention.
Fig. 3 shows the block schematic diagram of the Power Limitation amplifier combining another embodiment of the present invention.
Fig. 4 shows the block schematic diagram of the Power Limitation amplifier combining further embodiment of this invention.
Fig. 5 shows the block schematic diagram of the Power Limitation amplifier combining yet another embodiment of the invention.
Fig. 6 shows the block schematic diagram of this detector unit combining one embodiment of the invention.
Symbol description
100 class-D amplifier
12 gain amplification stage
13 pulse width modulators
14,15 feedback networks
16,18 power stages
19 load circuits
20,30,40,50 Power Limitation amplifiers
22 fall gain units
24,24 ' operational amplifiers
26,26 ', 26 " detector unit
262,264,265 voltage comparators
266 multiplexers
42 fall gain units
62,64 charge pumps
66,68 low pass filters
C1, C2 input capacitance
I1～I4 current source
M1～M7 transistor
R1～R4 resistance
RB resistance
SW1, SW2 switch
VB bias generator
Specific embodiment
Fig. 2 shows the block schematic diagram of the Power Limitation amplifier 20 combining one embodiment of the invention.Reference
Fig. 2, this Power Limitation amplifier 20 comprises a biasing voltage source VB, a fall gain unit 22, a computing
Amplifier 24, a detector unit 26, input capacitance C1 and multiple resistance R1 and RB.This operation amplifier
Device 24 has a positive input terminal, a negative input end and an outfan.This fall gain unit 22 is coupled to this electricity
Between resistance R1 and this negative input end of this operational amplifier 24.This resistance RB is coupled to this operational amplifier 24
This positive input terminal and this outfan between.
With reference to Fig. 2, this detector unit 26 is made up of two voltage comparators 262 and 264.This voltage comparator
262 in order to the default electricity of output signal VO and comparing this outfan resulting from this operational amplifier 24
Pressure value REFH, so as to producing control signal CP1.This voltage comparator 264 is in order to compare this output letter
A number VO and preset voltage value REFL, so as to producing control signal CP2.These signals CP1 and CP2
In order to change the resistance of this fall gain unit 22.In the present embodiment, this fall gain unit 22 is by two crystal
Pipe M1 and M2 is formed.This transistor M1 is coupled to this resistance R1, and this transistor M2 is coupled to this
Between this positive input terminal of transistor M1 and this operational amplifier 24.
Operationally, after analogue signal VIN is entered by an input of this Power Limitation amplifier 20,
Via this input capacitance C1 to filter the Dc bias of analog input signal.Then, according to resistance RA and electricity
The resistance ratio of resistance RB, signal A1 can be exaggerated (RB/RA) multiple to produce this output signal VO.At this
In embodiment, the resistance of resistance RA is added by the resistance of resistance R1 and the equivalent resistance of this fall gain unit 22
Always form, and the equivalent resistance of this fall gain unit 22 is determined by the conducting resistance of two transistor M1 and M2
Fixed.
When the magnitude of voltage of this output signal VO falls within this preset voltage value REFH and this preset voltage value
When between REFL, represent that the voltage amplitude of this analogue signal VIN is load tolerance interval, therefore this electricity
Pressure comparator 262 can produce this control signal CP1 positioned at logic 1 level, and this voltage comparator 264 meeting
Produce this control signal CP2 being located at logic 1 level, so as to fully on these transistors M1 and M2.
Now, the resistance of resistance RA is substantially equal to the resistance of resistance R1.
When the magnitude of voltage of this output signal VO is more than this preset voltage value REFH, represent this analogue signal
The voltage amplitude of VIN exceedes load tolerance interval.Now, this voltage comparator 262 can produce to be less than and patrol
Collect this control signal CP1 of 1 level, so as to partially ON this transistor M1.Therefore, this resistance RA
Resistance can be added up by the equivalent resistance of the resistance of resistance R1 and this transistor M1.Due to this resistance RA's
Resistance is lifted, and the amplification of this signal A1 can decline, and the voltage so as to limiting this output signal VO is little
In this preset voltage value REFH.
Similarly, when the magnitude of voltage of this output signal VO is less than this preset voltage value REFL, representing should
The voltage amplitude of analogue signal VIN exceedes load tolerance interval.Now, this voltage comparator 264 can produce
Raw this control signal CP2 less than logic 1 level, so as to partially ON this transistor M2.Therefore, this electricity
The resistance of resistance RA can be added up by the equivalent resistance of the resistance of resistance R1 and this transistor M2.Due to this electricity
The resistance lifting of resistance RA, the amplification of this signal A1 can decline, so as to limiting this output signal VO
Voltage is not less than this preset voltage value REFL.
Fig. 3 shows the block schematic diagram of the Power Limitation amplifier 30 combining another embodiment of the present invention, its
In middle Fig. 3, the element of similar Fig. 2 is shown with similar reference number.With reference to Fig. 3, this fall gain unit 22 '
It is made up of a transistor M3.What this transistor M3 was coupled to this resistance R1 and this operational amplifier 24 should
Between negative input end.
This detector unit 26 is made up of multiple voltage comparators 262,264 and 265 and a multiplexer 266.
Operationally, when the magnitude of voltage of this output signal VO falls within this preset voltage value REFH and this predeterminated voltage
When between value REFL, represent that the voltage amplitude of this analogue signal VIN is load tolerance interval, therefore should
Voltage comparator 262 can produce this control signal CP1 positioned at logic 1 level, and this voltage comparator 264
This control signal CP2 positioned at logic 1 level can be produced.It is more than one in the magnitude of voltage of this input signal VIN
During magnitude of voltage VCM, this multiplexer 266 selects to export this control signal CP1.In this input signal VIN
When magnitude of voltage is less than this magnitude of voltage VCM, this multiplexer 266 selects to export this control signal CP2.This voltage
Value VCM is the central value of this input signal VIN voltage amplitude.Due to the magnitude of voltage in this output signal VO
When falling between this preset voltage value REFH and this preset voltage value REFL, these control signals CP1 and
CP2 is logic 1 level, and therefore these transistors M1 and M2 is fully on.This output in this situation
Signal VO can be signal A1 (RB/RC) multiple.
When the magnitude of voltage of this output signal VO is more than this preset voltage value REFH, represent this analogue signal
The voltage amplitude of VIN exceedes load tolerance interval.By these voltage comparators 262,264 and 265 with
And the running of this multiplexer 266, this detector unit 26 ' can export this control signal less than logic 1 level
CT, so as to partially ON this transistor M3.Therefore, the resistance of this resistance RA can be by the resistance of resistance R1
Added up with the equivalent resistance of this transistor M3.Due to the resistance lifting of this resistance RA, this signal A1's
Amplification can decline, and the voltage so as to limiting this output signal VO is not more than this preset voltage value REFH.
When the magnitude of voltage of this output signal VO is less than this preset voltage value REFL, represent this analogue signal
The voltage amplitude of VIN exceedes load tolerance interval.By these voltage comparators 262,264 and 265 with
And the running of this multiplexer 266, this detector unit 26 ' can export this control signal less than logic 1 level
CT, so as to partially ON this transistor M3, it is pre- that the voltage so as to limiting this output signal VO is not less than this
If magnitude of voltage REFL.
Operational amplifier 24 illustrated in Fig. 2 and Fig. 3 is the differential input of both-end, the amplification type of Single-end output
State.However, input power method for limiting disclosed in this invention also can be used in the differential input of both-end, double
The amplifier kenel of end differential output, as shown in figure 4, the element of similar Fig. 2 is with similar ginseng in wherein Fig. 4
Examine numerical monitor.
With reference to Fig. 4, this operational amplifier 24 ' has a positive input terminal, a negative input end, a positive output end
With a negative output terminal.Analog input signal VIP and VIN anti-phase each other is by this Power Limitation amplifier 40
After a pair of differential input enters, inclined with the direct current filtering analog input signal via input capacitance C1 and C2
Pressure.Then, the resistance ratio according to resistance RD and resistance RB, signal A1 can be exaggerated (RB/RD) multiple
To produce this output signal VO.In the present embodiment, the resistance of resistance R1 is identical with the resistance of resistance R2,
The resistance of resistance R3 is identical with the resistance of resistance RB.
With reference to Fig. 4, this Power Limitation amplifier 40 additionally comprises a fall gain unit 42.This fall gain unit 42
It is made up of two transistor M5 and M6.This transistor M5 is coupled to this resistance R2, and this transistor M6
It is coupled between this transistor M5 and this negative input end of this operational amplifier 24.In the present embodiment, this
The breadth length ratio of a little transistor M5 and M6 is equal to the breadth length ratio of these transistors M1 and M2, therefore these crystal
The conducting resistance of pipe M5 and M6 can be equal to the conducting resistance of these transistors M1 and M2.Operationally, should
Fall gain unit 42 can be according to these control signals CP1 and CP2 to change its resistance.This fall gain unit 42
Operation principle be same as the operation principle of this fall gain unit 22, do not repeat here.
Fig. 5 shows the block schematic diagram of the Power Limitation amplifier 50 combining one embodiment of the invention, its
In middle Fig. 5, the element of similar Fig. 3 is shown with similar reference number.With reference to Fig. 5, this Power Limitation amplifier
50 additionally comprise a fall gain unit 52.This fall gain unit 52 is made up of a transistor M7.This transistor
M7 is coupled between this resistance R2 and this negative input end of this operational amplifier 24 '.In the present embodiment,
The breadth length ratio of this transistor M7 is equal to the breadth length ratio of this transistor M3 in Fig. 3.Operationally, this fall increases
Beneficial unit 42 can be according to this control signal CT to change its resistance.The operation principle phase of this fall gain unit 42
It is same as the operation principle of this fall gain unit 22 in Fig. 3, do not repeat here.
With reference to Fig. 4, the generation of these control signals CP1 and CP2 is except by these comparators 262 and 264
Outward, also can by other modes, such as one charge pump (charge pump) and produce.Fig. 6 display combines this
Invent a detector unit 26 of an embodiment " block schematic diagram.With reference to Fig. 6, this detector unit 26 " comprise
One comparator 262, a comparator 264, a charge pump 62, a charge pump 64, a low pass filter 66 with
And a low pass filter 68.
This charge pump 62 comprises a pull-up current source I1, an a switch SW1 and pull-down current source I2.This charging
Pump 64 comprises a pull-up current source I3, an a switch SW2 and pull-down current source I4.This charge pump 62 is in order to turn
Change the comparative result of this comparator 262, so as to producing this control signal CP1.This low pass filter 66 in order to
Filter the radio-frequency component of this control signal CP1.This charge pump 64 is tied in order to the comparison changing this comparator 264
Really, so as to producing this control signal CP2.This low pass filter 68 is in order to filter the height of this control signal CP2
Frequency composition.
Operationally, when the magnitude of voltage of this output signal VOP in Fig. 4 is more than this preset voltage value REFH
When, or during less than this preset voltage value REFL, these charge pumps 62 and 64 and these low pass filters
66 and 68 can together operate to produce this control signal CP1 less than logic 1 level, or are less than logic 1
This control signal CP2 of level, so as to controlling the resistance of these fall gain units 22 and 42 in Fig. 4.According to
This mode, the voltage of this output signal VO can be limited to this preset voltage value REFH and this preset voltage value
Between REFL.
The technology contents of the present invention and technical characterstic are disclosed as above, but are familiar with the personage of the technology still
It is potentially based on teachings of the present invention and disclosure and make a variety of replacements without departing substantially from spirit of the present invention and modification.Cause
This, protection scope of the present invention should be not limited to person disclosed in embodiment, and should include various without departing substantially from this
Bright replacement and modification, and covered by appended claim.
Claims (10)
1. a kind of Power Limitation amplifier, comprises：
One operational amplifier, comprises a first input end, one second input and one first outfan；
One first resistor；
One first fall gain unit, is coupled to this first input end of this first resistor and this operational amplifier
Between；
One detector unit, in order to compare at least one output signal and at least resulting from this operational amplifier
Preset voltage value, so as to producing at least one control signal；And
One second resistance, is coupled to this first input end of this operational amplifier and being somebody's turn to do of this operational amplifier
Between first outfan；
Wherein, this first fall gain unit according to this at least one control signal to change its resistance.
2. Power Limitation amplifier according to claim 1, wherein this first fall gain unit comprise：
One the first transistor, is coupled to this first resistor；And
One transistor seconds, be coupled to this first transistor and this operational amplifier this first input end it
Between；
Wherein, this first transistor and this transistor seconds are hindered with changing it according to this at least one control signal
Value.
3. Power Limitation amplifier according to claim 2, wherein this at least one preset voltage value comprise one
First preset voltage value and one second preset voltage value, this at least one output signal be more than this first preset
During magnitude of voltage, or when this at least one output signal is less than this second preset voltage value, this detector unit is produced
This at least one control signal raw is to change the resistance of this first transistor and this transistor seconds.
4. Power Limitation amplifier according to claim 3, wherein this first fall gain unit comprise：
One the first transistor, is coupled between this first resistor and this first input end of this operational amplifier；
Wherein, when this at least one output signal is more than first preset voltage value or at least one defeated at this
When going out signal less than second preset voltage value, this first transistor changes its resistance.
5. Power Limitation amplifier according to claim 1, wherein this operational amplifier further includes one second
Outfan, and this Power Limitation amplifier further includes：
One 3rd resistor；
One second fall gain unit, is coupled to this second input of this 3rd resistor and this operational amplifier
Between；
One the 4th resistance, is coupled to this second input of this operational amplifier and being somebody's turn to do of this operational amplifier
Between second outfan；
Wherein, this second fall gain unit according to this at least one control signal to change its resistance.
6. Power Limitation amplifier according to claim 5, wherein this first fall gain unit and this second
Each of fall gain unit comprises a first transistor and a transistor seconds, this first fall gain list
This first transistor in unit and this transistor seconds are connected in series in this first resistor and this operational amplifier
This first input end between, this second fall gain unit in this first transistor and this transistor seconds
It is connected in series between this 3rd resistor and this second input of this operational amplifier, this first fall gain
This first transistor in unit and this second fall gain unit and this transistor seconds are according to this at least one control
Signal processed is to change its resistance.
7. Power Limitation amplifier according to claim 6, wherein this at least one preset voltage value comprise one
First preset voltage value and one second preset voltage value, this at least one output signal be more than this first preset
During magnitude of voltage, or when this at least one output signal is less than this second preset voltage value, this detector unit is produced
This at least one control signal raw with change in this first fall gain unit and this second fall gain unit this
One transistor and the resistance of this transistor seconds.
8. Power Limitation amplifier according to claim 5, wherein this first fall gain unit and this second
Each of fall gain unit comprises a first transistor, this first crystalline substance in this first fall gain unit
Body pipe is connected in series between this first resistor and this first input end of this operational amplifier, this second fall
This first transistor in gain unit be connected in series in this 3rd resistor and this operational amplifier this second
Between input, and wherein this at least one preset voltage value comprises one first preset voltage value and one second pre-
If magnitude of voltage, when this at least one output signal is more than this first preset voltage value or at least one defeated at this
When going out signal less than this second preset voltage value, this detector unit produces this at least one control signal to change
The resistance of this first transistor in this first fall gain unit and this second fall gain unit.
9. Power Limitation amplifier according to claim 1, wherein this detector unit further includes：
One charging pump unit, this at least one output signal and at least one in order to receive this operational amplifier are pre-
If the comparative result of magnitude of voltage, so as to producing this at least one control signal；And
One filter cell, is coupled to this charging pump unit, in order to filter the height of this at least one control signal
Frequency part.
10. Power Limitation amplifier according to claim 9, wherein this at least one preset voltage value comprise
One first preset voltage value and one second preset voltage value, are more than this in this at least one output signal first pre-
If during magnitude of voltage, or when this at least one output signal is less than this second preset voltage value, this detector unit
Produce this at least one control signal to change the resistance of this first fall gain unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510450173.8A CN106411280A (en) | 2015-07-28 | 2015-07-28 | Power limitation amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510450173.8A CN106411280A (en) | 2015-07-28 | 2015-07-28 | Power limitation amplifier |
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| Publication Number | Publication Date |
|---|---|
| CN106411280A true CN106411280A (en) | 2017-02-15 |
Family
ID=58008684
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510450173.8A Pending CN106411280A (en) | 2015-07-28 | 2015-07-28 | Power limitation amplifier |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109688514A (en) * | 2018-12-26 | 2019-04-26 | 上海艾为电子技术股份有限公司 | A kind of high-voltage digital audio power amplification system |
| CN110518882A (en) * | 2018-05-21 | 2019-11-29 | 矽统科技股份有限公司 | Configurable formula amplifier module |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5245229A (en) * | 1992-02-28 | 1993-09-14 | Media Vision | Digitally controlled integrated circuit anti-clipping mixer |
| US6396934B1 (en) * | 1996-05-31 | 2002-05-28 | Sgs-Thomson Microelectronics S.A. | Analog audio filter for high frequencies |
| US20030179039A1 (en) * | 2002-03-22 | 2003-09-25 | Te-Yu Liang | Amplifying circuit capable of limiting amplitude of output signal supplied to a speaker |
| CN101106361A (en) * | 2006-07-12 | 2008-01-16 | 震一科技股份有限公司 | Mutually supplementary gain control circuit |
| CN101247124A (en) * | 2007-02-16 | 2008-08-20 | 松下电器产业株式会社 | Pll circuit and wireless device |
| US20080258796A1 (en) * | 2007-04-19 | 2008-10-23 | National Semiconductor Germany Ag | Circuit arrangement and method for limiting a signal voltage |
| US20110133837A1 (en) * | 2009-12-08 | 2011-06-09 | Hiroshi Komori | Variable gain amplifier |
| CN102281037A (en) * | 2010-06-11 | 2011-12-14 | 成都芯源系统有限公司 | Audio amplifier circuit using closed loop power output stage and control method thereof |
| US8139791B1 (en) * | 2005-01-24 | 2012-03-20 | National Semiconductor Corporation | Ground referenced audio headphone amplifier with low standby current |
-
2015
- 2015-07-28 CN CN201510450173.8A patent/CN106411280A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5245229A (en) * | 1992-02-28 | 1993-09-14 | Media Vision | Digitally controlled integrated circuit anti-clipping mixer |
| US6396934B1 (en) * | 1996-05-31 | 2002-05-28 | Sgs-Thomson Microelectronics S.A. | Analog audio filter for high frequencies |
| US20030179039A1 (en) * | 2002-03-22 | 2003-09-25 | Te-Yu Liang | Amplifying circuit capable of limiting amplitude of output signal supplied to a speaker |
| US8139791B1 (en) * | 2005-01-24 | 2012-03-20 | National Semiconductor Corporation | Ground referenced audio headphone amplifier with low standby current |
| CN101106361A (en) * | 2006-07-12 | 2008-01-16 | 震一科技股份有限公司 | Mutually supplementary gain control circuit |
| CN101247124A (en) * | 2007-02-16 | 2008-08-20 | 松下电器产业株式会社 | Pll circuit and wireless device |
| US20080258796A1 (en) * | 2007-04-19 | 2008-10-23 | National Semiconductor Germany Ag | Circuit arrangement and method for limiting a signal voltage |
| US20110133837A1 (en) * | 2009-12-08 | 2011-06-09 | Hiroshi Komori | Variable gain amplifier |
| CN102281037A (en) * | 2010-06-11 | 2011-12-14 | 成都芯源系统有限公司 | Audio amplifier circuit using closed loop power output stage and control method thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110518882A (en) * | 2018-05-21 | 2019-11-29 | 矽统科技股份有限公司 | Configurable formula amplifier module |
| CN110518882B (en) * | 2018-05-21 | 2023-08-18 | 矽统科技股份有限公司 | Configurable amplifier module |
| CN109688514A (en) * | 2018-12-26 | 2019-04-26 | 上海艾为电子技术股份有限公司 | A kind of high-voltage digital audio power amplification system |
| CN109688514B (en) * | 2018-12-26 | 2023-09-15 | 上海艾为电子技术股份有限公司 | High-voltage digital audio power amplifier system |
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Application publication date: 20170215 |