CN101562428B - Signal modulation device and control method thereof - Google Patents
Signal modulation device and control method thereof Download PDFInfo
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- CN101562428B CN101562428B CN2008100910707A CN200810091070A CN101562428B CN 101562428 B CN101562428 B CN 101562428B CN 2008100910707 A CN2008100910707 A CN 2008100910707A CN 200810091070 A CN200810091070 A CN 200810091070A CN 101562428 B CN101562428 B CN 101562428B
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- width modulation
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Abstract
The invention relates to a signal modulation device comprising a pulse width modulation module, a control module, a switching module and a feedback module, wherein the pulse width modulation module receives a data signal, and generates a first pulse width modulation signal and a second pulse width modulation signal according to the data signal and the feedback signal. The control module is electrically connected with the pulse width modulation module and generates a first switching control signal and a second switching control signal according to the first pulse width modulation signal and thesecond pulse width modulation signal. The switching module is electrically connected with the control module and outputs a driving signal to drive a load according to the first switching control signal and the second switching control signal. The feedback module is respectively electrically connected with the pulse width modulation module, the control module and the switching module, and generates and transmits a feedback signal to the pulse width modulation module according to the switching state of the switching module.
Description
Technical field
The invention relates to a kind of modulating signal device and control method thereof.
Background technology
Generally speaking, the modulating signal device that is applied to audio system is roughly divided into category-A and class ab ammplifier, and it is that the audio signal of simulation is directly exported to drive loud speaker (speaker).
Recently, the less D class A amplifier A of power consumption has replaced the application of category-A and class ab ammplifier gradually.The D class A amplifier A mainly is after being tuned as pulse signal via the audio signal with simulation, via handover module output switching signal, is converted to analog drive signal to drive loud speaker via filter again.And along with development of technology, also develop recently and no filtering D class A amplifier A (class D filterless amplifier), promptly be that switching signal is directly driven loud speaker as drive signal.
In the handover module of D class A amplifier A, as shown in Figure 1, it comprises switch 11～14.Wherein, switch the 11, the 13rd electrically connects a voltage feed end V
DD, and switch the 12, the 14th electrically connects an earth terminal GND, and by control signal A
01～A
04 Difference control switch 11～14.
The control of handover module generally is to be divided into quaternary modulation (quaternary modulation) and ternary modulation (ternary modulation).Below, the control mode of two kinds of D class A amplifier As will be described respectively.
As shown in Figure 2, the quaternary modulation is to have four kinds of operation Like attitudes.In time T
01, control signal A
01And control signal A
04 Control switch 11,14 is conducting, control signal A
02And control signal A
03 Control switch 12,13 is for ending.At this moment, node A exports the node voltage V of the accurate position of a high voltage
A, Node B is exported the node voltage V of the accurate position of a low-voltage
B, have one first an accurate L and load (for example loud speaker) 15 is sensed
01Drive signal.
In time T
02, control signal A
01And control signal A
03 Control switch 11,13 is for ending control signal A
02And control signal A
04 Control switch 12,14 is conducting.At this moment, node A exports the node voltage V of the accurate position of a low-voltage
A, the node voltage V of the accurate position of Node B output LOW voltage
B, have one the 3rd an accurate L and load 15 is sensed
03Drive signal.
In time T
03, control signal A
01And control signal A
03 Control switch 11,13 is conducting, control signal A
02And control signal A
04 Control switch 12,14 is for ending.At this moment, the node voltage V of the accurate position of node A output HIGH voltage
A, Node B is exported the node voltage V of the accurate position of a high voltage
B, have the 3rd an accurate L and it is also exported
03Drive signal.
In time T
04, control signal A
01And control signal A
04 Control switch 11,14 is for ending control signal A
02And control signal A
03 Control switch 12,13 is conducting.At this moment, the node voltage V of the accurate position of node A output LOW voltage
A, the node voltage V of the accurate position of Node B output HIGH voltage
B, have one second an accurate L and load 15 is sensed
02Drive signal.Wherein, the 3rd an accurate L
03Between first an accurate L
01Reach second an accurate L
02Between.
Please refer to shown in Figure 3ly, the ternary modulation is to have three kinds of operation Like attitudes, and different with the quaternary modulation be that it is at control output the 3rd an accurate L
03Drive signal mode only with among Fig. 2 in time T
12Control mode come control switch.
From the above, generally speaking, the change action of switch will cause extra switch cost, and the control mode of quaternary modulation, having the switching mode in two stages to be all the controlling and driving signal is the 3rd accurate position, though the ternary modulation only utilizes the switching in a stage, so it still can produce switch cost.Therefore, how to provide a kind of modulating signal device that can reduce power loss, real one of the current important topic that belongs to.
Summary of the invention
Because above-mentioned problem, the present invention's purpose is for providing a kind of modulating signal device and control method thereof that can reduce power loss.
For reaching above-mentioned purpose, the invention provides a kind of modulating signal device, it is to comprise a pulse-width modulation module, a control module, all die change pieces and a back coupling module.The pulse-width modulation module receives a data-signal, and produces one first pulse-width modulation signal and one second pulse-width modulation signal according to a data-signal and a feedback signal.Control module and pulse-width modulation module electrically connect, and produce one first switch-over control signal and one second switch-over control signal according to the first pulse-width modulation signal and the second pulse-width modulation signal.Handover module and control module electrically connect, and export a drive one load according to first switch-over control signal and second switch-over control signal.The back coupling module electrically connects with pulse-width modulation module, control module and handover module respectively, and produces a feedback signal to the pulse-width modulation module according to the switching state of handover module.
For reaching above-mentioned purpose, the invention provides a kind of control method of modulating signal device, wherein the modulating signal device has all die change pieces, and handover module has one first switch, a second switch, one the 3rd switch and one the 4th switch.The control method of modulating signal device comprises the following step: according to these switches that switch in the control signal control handover module is cut-off state; Has the drive signal of a floating by handover module output.
From the above, because of foundation modulating signal device of the present invention and control method thereof, its reset that passes through handover module is to the pulse-width modulation module, to improve fidelity.In addition, by switch-over control signal control handover module, when handover module is cut-off state, then by feedbacking the corresponding feedback signal of module decision output to the pulse-width modulation module, so as to reducing the change action of handover module, improve delivery efficiency to reduce power loss.
Description of drawings
Fig. 1 is for showing the schematic diagram of known D class A amplifier A output stage;
Fig. 2 to Fig. 3 is for showing the sequencing control figure of known D class A amplifier A;
Fig. 4 is for showing a kind of modulating signal schematic representation of apparatus according to preferred embodiment of the present invention;
Fig. 5 is for showing the schematic diagram according to a kind of handover module of preferred embodiment of the present invention;
Fig. 6 is for showing the sequencing control figure according to a kind of modulating signal device of preferred embodiment of the present invention; And
Fig. 7 is the flow chart of demonstration according to the control method of a kind of modulating signal device of preferred embodiment of the present invention.
[main element symbol description]
11～14: switch
15,7: load
2: the modulating signal device
3: the pulse-width modulation module
31: signal generating circuit
32: the positive feedback integrating circuit
321: the first positive integral units
322: the second positive integral units
323: just comparing the unit
33: the negative feedback integrating circuit
331: the first negative integral units
332: the second negative integral units
333: negative comparing unit
4: control module
5: handover module
51: the first switches
52: second switch
53: the three switches
54: the four switches
6: the back coupling module
61: the positive feedback control circuit
62: the negative feedback control circuit
A, B: node
A
01～A
04: control signal
A
1: data positive period of data-signal
A
2: the negative cycle data of data-signal
A
3, A
4, A
5, A
6: the computing signal
A
D1, A
D2: drive signal
A
Fb1: the positive feedback signal
A
Fb2: the negative feedback signal
A
P1: the first pulse-width modulation signal
A
P2: the second pulse-width modulation signal
A
S1: first switch-over control signal
A
S2: second switch-over control signal
C: capacitor
GND: earth terminal
L
01, L
11: the first accurate position
L
02, L
12: the second accurate position
L
03, L
13: the 3rd accurate position
OP: operational amplifier
R: resistor
S11～S12: step
T
01～T
04, T
11～T
13, T
21～T
23: the time
I
R1, V
R1: reference signal
V
A, V
B: node voltage
V
DD: the voltage feed end
Embodiment
Hereinafter with reference to correlative type, modulating signal device and control method thereof according to preferred embodiment of the present invention are described.
Please refer to shown in Figure 4ly, a kind of modulating signal device 2 of preferred embodiment of the present invention is to be applied to a D class A amplifier A, and it comprises a pulse-width modulation module 3, a control module 4, all die change pieces 5 and and feedbacks module 6.Pulse-width modulation module 3, control module 4 and back coupling module 6 electrically connect each other, and handover module 5 electrically connects with control module 4 and back coupling module 6 respectively.In present embodiment, control module 4 can be a microcontroller or a processor.
Pulse-width modulation module 3 receives a data-signal and exports one first pulse-width modulation signal A
P1And one second pulse-width modulation signal A
P2, wherein data-signal have one positive period data A
1An and negative cycle data A
2In addition, pulse-width modulation module 3 comprises a signal generating circuit 31, a positive feedback integrating circuit 32 and a negative feedback integrating circuit 33.Wherein, signal generating circuit 31 electrically connects with positive feedback integrating circuit 32 and negative feedback integrating circuit 33 respectively.
Signal generating circuit 31 produces at least one reference signal I
R1, in present embodiment, signal generating circuit 31 can be a circuit for generating triangular wave or a sawtooth wave generating circuit, and reference signal I
R1Can be a triangular signal or a sawtooth signal.
Positive feedback integrating circuit 32 has just relatively unit 323 of one first positive integral unit 321, one second positive integral unit 322 and.Wherein, the second positive integral unit 322 is respectively with the first positive integral unit 321, just relatively unit 323 and signal generating circuit 31 electrically connect.In addition, the first positive integral unit 321 and the second positive integral unit 322 comprise a resistor R, a capacitor C and an operational amplifier OP respectively, its visual demand and do topology and change.
The first positive integral unit 321 is according to data A positive period
1, a reference signal V
R1And feedback module 6 and one of export positive feedback signal A
Fb1And produce a computing signal A
3, and with computing signal A
3Export the second positive integral unit 322 to.
The second positive integral unit 322 receives computing signal A
3, and according to reference signal I
R1, reference signal V
R1And computing signal A
3Produce a computing signal A
4, and with computing signal A
4Export just relatively unit 323 to.
Just relatively unit 323 for example is a comparator, and it electrically connects with the first positive integral unit 321 and the second positive integral unit 322 respectively, and receives computing signal A
3And computing signal A
4In addition, just comparing unit 323 according to computing signal A
3And computing signal A
4Export the first pulse-width modulation signal A
P1
Please continue with reference to shown in Figure 4, negative feedback integrating circuit 33 has one first negative integral unit 331, one second a negative integral unit 332 and a negative comparing unit 333.Wherein, the second negative integral unit 332 electrically connects with the first negative integral unit 331, negative comparing unit 333 and signal generating circuit 31 respectively.
The first negative integral unit 331 and the second negative integral unit 332 are identical with the first positive integral unit 321 and the second positive integral unit 322 respectively, comprise a resistor R, a capacitor C and an operational amplifier OP respectively, certainly its also visual demand and do topology and change.
The first negative integral unit 331 is according to negative cycle data A
2, reference signal V
R1And feedback module 6 and one of export negative feedback signal A
Fb2And produce a computing signal A
5, and with computing signal A
5Export the second negative integral unit 332 to.
The second negative integral unit 332 receives computing signal A
5, and according to reference signal I
R1, reference signal V
R1And computing signal A
5Produce a computing signal A
6, and with computing signal A
6Export negative comparing unit 333 to.
Negative comparing unit 333 for example is a comparator, and it electrically connects with the first negative integral unit 331 and the second negative integral unit 332 respectively, and receives computing signal A
5And computing signal A
6In addition, negative comparing unit 333 is according to computing signal A
5And computing signal A
6Export one second pulse-width modulation signal A
P2
Please continue with reference to shown in Figure 4, control module 4 receives and the foundation first pulse-width modulation signal A
P1And the second pulse-width modulation signal A
P2And produce one first switch-over control signal A
S1And one second switch-over control signal A
S2Handover module 5 receives and the foundation first switch-over control signal A
S1And the second switch-over control signal A
S2Output drive signal A
D1, A
D2To drive a load 7, wherein load 7 for example is a loud speaker.In addition, back coupling module 6 also receives drive signal A simultaneously
D1, A
D2
The back coupling module 6 of present embodiment comprises a positive feedback control circuit 61 and a negative feedback control circuit 62, and it electrically connects with control module 4 and handover module 5 respectively.In addition, positive feedback control circuit 61 is according to drive signal A
D1And generation positive feedback signal A
Fb1, and be sent to pulse-width modulation module 3; Negative feedback control circuit 62 is according to drive signal A
D2And generation negative feedback signal A
Fb2, and be sent to pulse-width modulation module 3.In this, feedback module 6 one of to export feedback signal and promptly comprise positive feedback signal A
Fb1And negative feedback signal A
Fb2
Please be simultaneously with reference to shown in Figure 5, handover module 5 can comprise a semibridge system commutation circuit or a full-bridge type commutation circuit.In present embodiment, handover module 5 is the example explanation with the full-bridge type commutation circuit, and therefore, back coupling module 6 comprises positive feedback control circuit 61 and negative feedback control circuit 62.Yet, present embodiment and non-limiting back coupling module 6 need comprise positive feedback control circuit 61 and negative feedback control circuit 62 simultaneously, when handover module 5 is the semibridge system commutation circuit, feedback module 6 comprise positive feedback control circuit 61 or negative feedback control circuit 62 one of them, singly feedback control to form one.What is more, in present embodiment, back coupling module 6 is not a necessary element, knows this operator, when back coupling module 6 being removed.
Handover module 5 comprises one first switch 51, a second switch 52, one the 3rd switch 53 and one the 4th switch 54.Wherein, first switch 51 electrically connects with second switch 52, and the 3rd switch 53 and the 4th switch 54 electrically connect.
One end of load 7 electrically connects with first switch 51 and second switch 52 respectively, and the other end of load 7 electrically connects with the 3rd switch 53 and the 4th switch 54 respectively.In present embodiment, first switch 51, second switch 52, the 3rd switch 53 and the 4th switch 54 can be a transistor.
In present embodiment, the state of handover module 5 is by the first switch-over control signal A
S1And the second switch-over control signal A
S2Control is in this, with the first switch-over control signal A
S1Control first switch 51 and the 4th switch 54, the second switch-over control signal A
S2Control second switch 52 and the 3rd switch 53 are the example explanation.
Please be simultaneously with reference to shown in Figure 6, in a very first time T
21, the first switch-over control signal A
S1Control first switch 51 and the 4th switch 54 is conducting state, the second switch-over control signal A
S2Control second switch 52 and the 3rd switch 53 are cut-off state.At this moment, the drive signal A that exported of handover module 5
D1Be high levle signal, drive signal A
D2Be the low level signal, and make 6 outputs of back coupling module have one first an accurate L
11Feedback signal.
In one second time T
22, the first switch-over control signal A
S1And the second switch-over control signal A
S2Control first switch, 51 to the 4th switches 54 and be all cut-off state.At this moment, the drive signal A that exported of handover module 5
D1, A
D2And be suspension joint (floating) state.At this moment, feedback module 6 after judging that drive signal is floating, will export and have one the 3rd an accurate L
13Feedback signal.
At this moment, first switch, 51 to the 4th switches 54 in the handover module 5 all be in cut-off state and without any change action, therefore can reduce the switch cost of switch, whereby, the modulating signal device 2 of present embodiment can reduce power loss.
In one the 3rd time T
23, the first switch-over control signal A
S1Control first switch 51 and the 4th switch 54 is cut-off state, the second switch-over control signal A
S2Control second switch 52 and the 3rd switch 53 are conducting state.At this moment, the drive signal A that exported of handover module 5
D1Be low level signal, drive signal A
D2Be the high levle signal, and make 6 outputs of back coupling module have one second an accurate L
12Feedback signal, and the 3rd an accurate L
13Between first an accurate L
11Reach second an accurate L
12Between.
Please refer to shown in Figure 7, control method according to preferred embodiment of the present invention is the modulating signal device (shown in the 4th figure) that is applied to above-mentioned preferred embodiment, wherein the modulating signal device has all die change pieces, and handover module has one first switch, a second switch, one the 3rd switch and one the 4th switch.Control method of the present invention comprises that step S11 is to step S12.
Step S11 is that these switches of controlling in the handover module according to a switching control signal are cut-off state.Step S12 has the drive signal of a floating by handover module output.
What deserves to be mentioned is that above-mentioned step S11 does not limit its execution sequence to step S12, it can be exchanged mutually.Wherein detailed control mode describes in detail in the foregoing description, in the lump so no longer given unnecessary details in this.
In sum, because of according to modulating signal device of the present invention and control method thereof, be that the drive signal that handover module is exported is feedback via feedback circuit to the pulse-width modulation module, to improve fidelity.When load does not have the driving demand, even the switch in the handover module remains on cut-off state, therefore can reduce switch cost, improve delivery efficiency so as to reducing power loss.Therefore and this moment, handover module was output as floating, must the feedback signal of a fixing accurate position be exported in the drive signal conversion of floating by feedbacking module, for the usefulness of the pulse-width modulation module arithmetic judgement of prime.
The above only is an illustrative, but not is restricted person.Anyly do not break away from spirit of the present invention and category, and, all should be contained in the appended claim scope its equivalent modifications of carrying out or change.
Claims (13)
1. the control method of a modulating signal device, wherein this modulating signal device has all die change pieces, and this handover module has one first switch, a second switch, one the 3rd switch and one the 4th switch, and this control method comprises the following step:
These switches of controlling in this handover module according to a switching control signal are cut-off state; And
Drive signal to the one back coupling module that has a floating by this handover module output; And
Export feedback signal to the pulse-width modulation module of a fixing accurate position by the drive signal of this this floating of back coupling module converts.
2. as 1 described control method of claim the, wherein this handover module is controlled by this switching signal with one first switch-over control signal and one second switch-over control signal.
3. as 1 described control method of claim the, wherein this pulse-width modulation module produces one first pulse-width modulation signal and one second pulse-width modulation signal according to this feedback signal and a data-signal.
4. as 3 described control methods of claim the, wherein a control module is to produce this switch-over control signal to control this handover module according to this first pulse-width modulation signal and this second pulse-width modulation signal.
5. modulating signal device comprises:
One pulse-width modulation module is to receive a data-signal, and produces one first pulse-width modulation signal and one second pulse-width modulation signal according to this data-signal and a feedback signal;
One control module is to electrically connect with this pulse-width modulation module, and produces one first switch-over control signal and one second switch-over control signal according to this first pulse-width modulation signal and this second pulse-width modulation signal;
All die change pieces are to electrically connect with this control module, and export a drive one load according to this first switch-over control signal and this second switch-over control signal; And
One back coupling module is to electrically connect with this pulse-width modulation module, this control module and this handover module respectively, and produces this feedback signal to this pulse-width modulation module according to the switching state of this handover module.
6. as 5 described modulating signal devices of claim the, wherein this pulse-width modulation module comprises:
One positive feedback integrating circuit, be receive and according to this data-signal one positive period data and this feedback signal produce this first pulse-width modulation signal;
One negative feedback integrating circuit is to receive and produce this second pulse-width modulation signal according to negative cycle data and this feedback signal of this data-signal; And
One signal generating circuit is to electrically connect with this positive feedback integrating circuit and this negative feedback integrating circuit, and this signal generating circuit produces at least one reference signal, and transmits it to this positive feedback integrating circuit and this negative feedback integrating circuit respectively.
7. as 6 described modulating signal devices of claim the, wherein this positive feedback integrating circuit comprises:
One first positive integral unit, receive and according to this data-signal this positive period data and this feedback signal produce one first computing signal;
One second positive integral unit is to electrically connect with this first positive integral unit, and produces one second computing signal according to this first computing signal and this reference signal; And
One is just comparing the unit, is to electrically connect with this first positive integral unit and this second positive integral unit respectively, and exports this first pulse-width modulation signal according to this first computing signal and this second computing signal.
8. as 6 described modulating signal devices of claim the, wherein this negative feedback integrating circuit comprises:
One first negative integral unit receives and produces one first computing signal according to these negative cycle data and this feedback signal of this data-signal;
One second negative integral unit is to electrically connect with this first negative integral unit, and produces one second computing signal according to this first computing signal and this reference signal; And
One negative comparing unit is to electrically connect with this first negative integral unit and this second negative integral unit respectively, and exports this second pulse-width modulation signal according to this first computing signal and this second computing signal.
9. as 6 described modulating signal devices of claim the, wherein this signal generating circuit is a circuit for generating triangular wave or a sawtooth wave generating circuit, and this reference signal is a triangular signal or a sawtooth signal.
10. as 6 described modulating signal devices of claim the, wherein this back coupling module comprises a positive feedback control circuit, be to electrically connect with this positive feedback integrating circuit, this control module and this handover module respectively, and produce this feedback signal that comprises a positive feedback signal according to this drive signal.
11. as 6 described modulating signal devices of claim the, wherein this back coupling module comprises a negative feedback control circuit, be to electrically connect with this negative feedback integrating circuit, this control module and this handover module respectively, and produce this feedback signal that comprises a negative feedback signal according to this drive signal.
12. as 5 described modulating signal devices of claim the, wherein this handover module comprises:
One first switch;
One second switch, one end are to electrically connect with this first switch and a load respectively;
One the 3rd switch; And
One the 4th switch, one end are to electrically connect with the 3rd switch and this load respectively.
13. as 5 described modulating signal devices of claim the, it can be applicable to a D class A amplifier A.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100910707A CN101562428B (en) | 2008-04-16 | 2008-04-16 | Signal modulation device and control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100910707A CN101562428B (en) | 2008-04-16 | 2008-04-16 | Signal modulation device and control method thereof |
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| CN101562428A CN101562428A (en) | 2009-10-21 |
| CN101562428B true CN101562428B (en) | 2011-06-15 |
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| CN103312306A (en) * | 2013-05-09 | 2013-09-18 | 上海三一重机有限公司 | Pulse-width modulation method for large-power alternating-current transmission electric-driving mine car |
| TWI781532B (en) * | 2021-02-19 | 2022-10-21 | 晶豪科技股份有限公司 | Over charge protection method and voltage converter using the over charge protection method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5077539A (en) * | 1990-12-26 | 1991-12-31 | Apogee Technology, Inc. | Switching amplifier |
| US5111319A (en) * | 1987-07-21 | 1992-05-05 | Thorn Emi Plc | Drive circuit for providing at least one of the output waveforms having at least four different voltage levels |
| CN1783716A (en) * | 2004-12-03 | 2006-06-07 | 普诚科技股份有限公司 | Pulse amplitude modulating method and circuit for improving D class audio amplifier property |
| CN1859000A (en) * | 2005-05-08 | 2006-11-08 | 中国科学院半导体研究所 | Feedback type full difference modulator |
| CN101150297A (en) * | 2006-09-18 | 2008-03-26 | 晶豪科技股份有限公司 | Half-wave impulse bandwidth modulation D audio amplifier |
-
2008
- 2008-04-16 CN CN2008100910707A patent/CN101562428B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5111319A (en) * | 1987-07-21 | 1992-05-05 | Thorn Emi Plc | Drive circuit for providing at least one of the output waveforms having at least four different voltage levels |
| US5077539A (en) * | 1990-12-26 | 1991-12-31 | Apogee Technology, Inc. | Switching amplifier |
| CN1783716A (en) * | 2004-12-03 | 2006-06-07 | 普诚科技股份有限公司 | Pulse amplitude modulating method and circuit for improving D class audio amplifier property |
| CN1859000A (en) * | 2005-05-08 | 2006-11-08 | 中国科学院半导体研究所 | Feedback type full difference modulator |
| CN101150297A (en) * | 2006-09-18 | 2008-03-26 | 晶豪科技股份有限公司 | Half-wave impulse bandwidth modulation D audio amplifier |
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