CN113630688B - Direct current servo circuit - Google Patents
Direct current servo circuit Download PDFInfo
- Publication number
- CN113630688B CN113630688B CN202110898524.7A CN202110898524A CN113630688B CN 113630688 B CN113630688 B CN 113630688B CN 202110898524 A CN202110898524 A CN 202110898524A CN 113630688 B CN113630688 B CN 113630688B
- Authority
- CN
- China
- Prior art keywords
- direct current
- current signal
- electrically connected
- capacitor
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000008878 coupling Effects 0.000 claims abstract description 36
- 238000010168 coupling process Methods 0.000 claims abstract description 36
- 238000005859 coupling reaction Methods 0.000 claims abstract description 36
- 230000004044 response Effects 0.000 claims abstract description 18
- 239000003990 capacitor Substances 0.000 claims description 42
- 230000009467 reduction Effects 0.000 abstract description 2
- 230000006978 adaptation Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005236 sound signal Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/181—Low-frequency amplifiers, e.g. audio preamplifiers
- H03F3/183—Low-frequency amplifiers, e.g. audio preamplifiers with semiconductor devices only
- H03F3/187—Low-frequency amplifiers, e.g. audio preamplifiers with semiconductor devices only in integrated circuits
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/03—Indexing scheme relating to amplifiers the amplifier being designed for audio applications
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Multimedia (AREA)
- Power Engineering (AREA)
- Amplifiers (AREA)
Abstract
The invention discloses a direct current servo circuit, which comprises: a direct current amplifier; the positive phase end of the direct current amplifier is electrically connected with an alternating current signal coupling network or a high-pass filter, the low-frequency response of the positive phase end of the direct current amplifier is reduced through the alternating current signal coupling network or the high-pass filter, and the alternating current signal coupling network or the high-pass filter is electrically connected with the direct current signal input end; the frequency selection network is electrically connected with the direct current amplifier, the frequency selection network and the direct current amplifier form an inverting amplifier, the low-frequency response of the negative phase end of the direct current amplifier is reduced through the frequency selection network, the alternating current signal coupling network or the high-pass filter is electrically connected with the frequency selection network, and the frequency selection network is electrically connected with the direct current signal input end; the coupling network is connected with the output end of the direct current amplifier and the direct current signal output end; a substantial reduction of the dc offset is achieved.
Description
Technical Field
The invention relates to the technical field of amplifying circuits, in particular to a direct current servo circuit.
Background
Most of the existing sound circuits are composed of differential circuits or symmetrical circuits in various forms, if the output midpoint direct-current voltage of a front-stage amplifying circuit is higher, a rear-stage power amplifying circuit deviates from the original symmetrical working state, and symmetrical audio signals cannot be amplified better. That is, a circuit with an offset in the output midpoint, in which case the amplified signal is already a distorted signal, in the presence of significant distortion itself; even more serious, if the midpoint of the output is shifted by too high a dc voltage, this may cause the speaker connected thereto to not work well, and in severe cases may even burn the speaker connected thereto. To reduce the dc offset voltage at the output end of the amplifier, the dc offset voltage is generally improved by adding a zero-setting circuit and a dc servo circuit, or the problem that the dc offset voltage exists at the output end of the amplifier is thoroughly solved.
The existing direct current servo circuit is generally composed of a low-pass filter and an integrating circuit, is complex in design in order to be compatible with a current module and a voltage module, and is provided with a plurality of connecting wires at a plurality of positions, so that the whole size of the circuit is directly larger; meanwhile, the DC offset reduction effect at the output and input ends is also more general.
Accordingly, a need exists for a dc servo circuit that addresses one or more of the above issues.
Disclosure of Invention
The present invention provides a dc servo circuit to solve one or more of the problems of the prior art. The invention adopts the technical proposal for solving the problems that: a dc servo circuit, comprising: the direct current amplifier is electrically connected with the positive power supply and the negative power supply;
The positive phase end of the direct current amplifier is electrically connected with an alternating current signal coupling network or a high-pass filter, the low-frequency response of the positive phase end of the direct current amplifier is reduced through the alternating current signal coupling network or the high-pass filter, and the alternating current signal coupling network or the high-pass filter is electrically connected with the direct current signal input end;
The frequency selection network is electrically connected with the direct current amplifier, the frequency selection network and the direct current amplifier form an inverting amplifier, the low-frequency response of the negative phase end of the direct current amplifier is reduced through the frequency selection network, the alternating current signal coupling network or the high-pass filter is electrically connected with the frequency selection network, and the frequency selection network is electrically connected with the direct current signal input end;
The coupling network is connected with the output end of the direct current amplifier and the direct current signal output end;
the direct current signal input end is electrically connected with the direct current signal output end, and the coupling network counteracts the direct current inverted signal output by the direct current amplifier and the input direct current signal.
Further, the direct current signal input end and the direct current signal output end are the same end point.
Further, the alternating current signal coupling network and the high-pass filter generate floating negative voltage at the positive phase end of the direct current amplifier.
Further, the alternating current signal coupling network comprises a first capacitor and a first resistor; the output end of the first resistor is grounded, the input end of the first resistor is electrically connected with the positive end of the direct current amplifier and the output end of the first capacitor, and the input end of the first capacitor is electrically connected with the direct current signal input end.
Further, the frequency-selecting network comprises a second capacitor and a second resistor, the coupling network comprises a third resistor, and the direct current signal input end and the direct current signal output end are the same end point; the input end of the second resistor is electrically connected with the direct current signal input end, the output end of the second resistor is electrically connected with the input end of the second capacitor and the negative phase end of the direct current amplifier, the output end of the second capacitor is electrically connected with the output end of the direct current amplifier and the output end of the third resistor, and the input end of the third resistor is electrically connected with the direct current signal input end.
Further, the larger the values of the first capacitor and the first resistor are, the lower the low-frequency response of the non-inverting terminal of the direct current amplifier is.
Further, the larger the values of the second capacitor and the second resistor are, the lower the low-frequency response of the frequency-selective network is.
Further, a third capacitor is included, the third capacitor being a power supply decoupling capacitor, the third capacitor being between the positive power supply and the negative power supply.
The direct current signal output by the amplifier and the input direct current signal offset are counteracted, the active direct current servo function is achieved, the direct current offset of the direct current input end and the direct current offset of the output end are greatly reduced, and the direct current servo circuit has low power consumption, high efficiency and wide adaptation range. The practical value of the invention is greatly improved.
Drawings
FIG. 1 is a schematic diagram of a DC servo circuit according to the present invention;
fig. 2 is a schematic block diagram of a dc servo circuit according to the present invention.
[ Reference numerals ]
101··Adder/direct current cancellation circuit input positive polarity pulsating direct current signal+pulsating direct current signal output by reverse phase direct current servo circuit
201- & Gtnormal phase signal, reverse phase signal and frequency selecting network
301.A.reverse DC servo circuit.
Detailed Description
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention briefly described above will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The invention may be embodied in many other forms than described herein without departing from the spirit or scope of the invention as defined in the following claims.
As shown in fig. 1, the present invention discloses a dc servo circuit, which includes: a direct current amplifier AMP electrically connected to the positive power supply VCC and the negative power supply VEE;
The positive phase end of the direct current amplifier AMP is electrically connected with an alternating current signal coupling network or a high-pass filter, the low-frequency response of the positive phase end of the direct current amplifier AMP is reduced through the alternating current signal coupling network or the high-pass filter, and the alternating current signal coupling network or the high-pass filter is electrically connected with the direct current signal input end;
The frequency-selecting network is electrically connected with the direct current amplifier AMP, the frequency-selecting network and the direct current amplifier AMP form an inverting amplifier, the low-frequency response of the negative phase end of the direct current amplifier AMP is reduced through the frequency-selecting network, the alternating current signal coupling network or the high-pass filter is electrically connected with the frequency-selecting network, and the frequency-selecting network is electrically connected with the direct current signal input end;
the coupling network is connected with the output end of the direct current amplifier AMP and the direct current signal output end;
The direct current signal input end is electrically connected with the direct current signal output end, and the coupling network counteracts the direct current inverted signal output by the direct current amplifier AMP and the input direct current signal.
Specifically, as shown in fig. 1, the ac signal coupling network includes a first capacitor C01 and a first resistor R01; the output end of the first resistor R01 is grounded, the R01 input end of the first resistor is electrically connected with the positive end of the direct current amplifier AMP and the output end of the first capacitor C01, and the input end of the first capacitor C01 is electrically connected with the direct current signal input end. The frequency selection network comprises a second capacitor C02 and a second resistor R02, the coupling network comprises a third resistor R03, and the direct current signal input end and the direct current signal output end are the same end point; the input end of the second resistor R02 is electrically connected with the direct current signal input end, the output end of the second resistor R02 is electrically connected with the input end of the second capacitor C02 and the inverting end of the direct current amplifier AMP, the output end of the second capacitor C02 is electrically connected with the output end of the direct current amplifier AMP and the output end of the third resistor R03, and the input end of the third resistor R03 is electrically connected with the direct current signal input end.
It should be noted that the dc amplifier AMP is a low dc offset, high input impedance, high gain, high speed amplifier. The low frequency response of the high pass filter is very low (approximately 0 Hz) and the low frequency response of the ac signal coupling network is approximately 0Hz. The direct current amplifier AMP is connected into an inverting amplifier, and one end of the direct current amplifier AMP is grounded by combining with the first resistor R01, so that the positive end of the direct current amplifier AMP is virtual ground, and a weak floating negative voltage is generated.
After the second resistor R02, the second capacitor C02 and the dc amplifier AMP form an inverting amplifier, the low-frequency response of the frequency selection network formed by the second resistor R02 and the second capacitor C02 is similar to 0Hz because the values of the second resistor R02 and the second capacitor C02 are very large. Further, the larger the values of the second capacitor C02 and the second resistor R02, the lower the low-frequency response of the frequency-selective network. Similarly, the values of the first resistor R01 and the first capacitor C01 are also large, so that the low-frequency response of the ac signal coupling network formed by the first resistor R01 and the first capacitor C01 is similar to 0Hz, and the larger the values of the first capacitor C01 and the first resistor R01 are, the lower the low-frequency response of the non-inverting terminal of the dc amplifier AMP is.
Therefore, a dc inverted signal with a frequency of approximately 0Hz, which is opposite to the phase of the dc input, is output at the output of the dc amplifier AMP, and this dc inverted signal is coupled via the coupling network (third resistor R03) so that the dc signals at the dc input, output (input-output) and input cancel each other.
Specifically, as shown in fig. 1, the capacitor further includes a third capacitor R03, where the third capacitor R03 is a power decoupling capacitor, and the third capacitor R03 is connected in parallel between the positive power source VCC and the negative power source VEE.
As shown in fig. 2, the dc signal output and input terminals are connected together, the positive phase signal, the inverted signal and the frequency-selecting network are coupled by dc and then enter the inverted dc servo circuit 301, and the pulsating dc signal output by the inverted dc servo circuit 301 is coupled by dc and then is cancelled by the positive polarity pulsating dc signal input by the adder or the dc cancellation circuit. Therefore, the implementation method can be divided into three parts, namely an inverted direct current servo circuit 301 for output, a normal phase signal, an inverted signal and a frequency selecting network 201 for input, wherein the input and output ends of the direct current signal comprise a positive polarity pulse direct current signal which is input by a direct current coupled adder/direct current offset circuit and a pulse direct current signal 101 which is output by the inverted direct current servo circuit, so that offset is realized at the input and output ends (same end points) of the direct current signal.
In summary, the direct current amplifier AMP, the alternating current signal coupling network, the frequency selecting network, the coupling network and other circuits are connected together through ingenious layout, so that the overall size of the direct current servo circuit is reduced, the direct current signal input end and the direct current signal output end are combined at the same endpoint, the direct current signal output by the amplifier and the input direct current signal are counteracted, the active direct current servo function is achieved, the direct current offset of the direct current input end and the direct current offset of the output end are greatly reduced, and the circuit has low power consumption, high efficiency and wide adaptation range. The practical value of the invention is greatly improved.
The foregoing examples are merely representative of one or more embodiments of the present invention and are described in more detail and are not to be construed as limiting the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of the invention should be assessed as that of the appended claims.
Claims (8)
1. A dc servo circuit, comprising: the direct current amplifier is electrically connected with the positive power supply and the negative power supply;
The positive phase end of the direct current amplifier is electrically connected with an alternating current signal coupling network or a high-pass filter, the low-frequency response of the positive phase end of the direct current amplifier is reduced through the alternating current signal coupling network or the high-pass filter, and the alternating current signal coupling network or the high-pass filter is electrically connected with the direct current signal input end;
The frequency selection network is electrically connected with the direct current amplifier, the frequency selection network and the direct current amplifier form an inverting amplifier, the low-frequency response of the negative phase end of the direct current amplifier is reduced through the frequency selection network, the alternating current signal coupling network or the high-pass filter is electrically connected with the frequency selection network, and the frequency selection network is electrically connected with the direct current signal input end;
The coupling network is connected with the output end of the direct current amplifier and the direct current signal output end;
the direct current signal input end is electrically connected with the direct current signal output end, and the coupling network counteracts the direct current inverted signal output by the direct current amplifier and the input direct current signal.
2. The dc servo circuit of claim 1 wherein the dc signal input and the dc signal output are at the same end point.
3. The dc servo circuit of claim 1 wherein the ac signal coupling network and the high pass filter produce a floating negative voltage at the non-inverting terminal of the dc amplifier.
4. The direct current servo circuit of claim 1, wherein the alternating current signal coupling network comprises a first capacitor and a first resistor;
The output end of the first resistor is grounded, the input end of the first resistor is electrically connected with the positive end of the direct current amplifier and the output end of the first capacitor, and the input end of the first capacitor is electrically connected with the direct current signal input end.
5. The direct current servo circuit of claim 4, wherein the frequency selective network comprises a second capacitor and a second resistor, the coupling network comprises a third resistor, and the direct current signal input end and the direct current signal output end are the same end point;
The input end of the second resistor is electrically connected with the direct current signal input end, the output end of the second resistor is electrically connected with the input end of the second capacitor and the negative phase end of the direct current amplifier, the output end of the second capacitor is electrically connected with the output end of the direct current amplifier and the output end of the third resistor, and the input end of the third resistor is electrically connected with the direct current signal input end.
6. The dc servo circuit of claim 4 wherein the larger the first capacitor and the first resistor, the lower the low frequency response of the non-inverting terminal of the dc amplifier.
7. The dc servo circuit of claim 5 wherein the larger the second capacitor and the second resistor, the lower the low frequency response of the frequency selective network.
8. The dc servo circuit of claim 1 further comprising a third capacitor, the third capacitor being a power decoupling capacitor, the third capacitor being between the positive power supply and the negative power supply.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110898524.7A CN113630688B (en) | 2021-08-05 | 2021-08-05 | Direct current servo circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110898524.7A CN113630688B (en) | 2021-08-05 | 2021-08-05 | Direct current servo circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113630688A CN113630688A (en) | 2021-11-09 |
| CN113630688B true CN113630688B (en) | 2024-05-17 |
Family
ID=78382936
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110898524.7A Active CN113630688B (en) | 2021-08-05 | 2021-08-05 | Direct current servo circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113630688B (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004153699A (en) * | 2002-10-31 | 2004-05-27 | Seiko Epson Corp | Single phase/differential conversion circuit |
| CN202634379U (en) * | 2012-07-03 | 2012-12-26 | 四川蓝讯宝迩电子科技有限公司 | Direct-current coupling low-pass RC (remote control) active filter |
| CN102957319A (en) * | 2011-08-29 | 2013-03-06 | 邱月美 | Power inverter pulse-width modulation control circuit and method |
| CN103078488A (en) * | 2012-12-29 | 2013-05-01 | 东南大学 | Digital power factor correction controller with fast transient response function |
| CN103095233A (en) * | 2013-01-23 | 2013-05-08 | 电子科技大学 | Amplifier eliminating direct current offsets |
| CN106602851A (en) * | 2017-01-11 | 2017-04-26 | 哈尔滨工业大学深圳研究生院 | Low frequency pulse current ripple inhibition circuit suitable for pulse load |
| CN207410306U (en) * | 2017-09-28 | 2018-05-25 | 重庆中科芯亿达电子有限公司 | A kind of alternating current-direct current signal distinguishes amplifying circuit |
| CN109495137A (en) * | 2019-01-15 | 2019-03-19 | 广东志成冠军集团有限公司 | A kind of the signal coupled system and method for subsea DC power transmission cable |
| CN208836000U (en) * | 2018-09-18 | 2019-05-07 | 广州市特沃能源管理有限公司 | A kind of adjustable DC output circuit |
| CN212660148U (en) * | 2020-05-20 | 2021-03-05 | 海能达通信股份有限公司 | Voltage-controlled oscillator and frequency generator |
| CN112653455A (en) * | 2020-12-04 | 2021-04-13 | 电子科技大学 | High-frequency low-power-consumption self-mixing millimeter wave voltage-controlled oscillator |
| CN215773545U (en) * | 2021-08-05 | 2022-02-08 | 东莞凯韵科技有限公司 | Direct current servo circuit |
-
2021
- 2021-08-05 CN CN202110898524.7A patent/CN113630688B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004153699A (en) * | 2002-10-31 | 2004-05-27 | Seiko Epson Corp | Single phase/differential conversion circuit |
| CN102957319A (en) * | 2011-08-29 | 2013-03-06 | 邱月美 | Power inverter pulse-width modulation control circuit and method |
| CN202634379U (en) * | 2012-07-03 | 2012-12-26 | 四川蓝讯宝迩电子科技有限公司 | Direct-current coupling low-pass RC (remote control) active filter |
| CN103078488A (en) * | 2012-12-29 | 2013-05-01 | 东南大学 | Digital power factor correction controller with fast transient response function |
| CN103095233A (en) * | 2013-01-23 | 2013-05-08 | 电子科技大学 | Amplifier eliminating direct current offsets |
| CN106602851A (en) * | 2017-01-11 | 2017-04-26 | 哈尔滨工业大学深圳研究生院 | Low frequency pulse current ripple inhibition circuit suitable for pulse load |
| CN207410306U (en) * | 2017-09-28 | 2018-05-25 | 重庆中科芯亿达电子有限公司 | A kind of alternating current-direct current signal distinguishes amplifying circuit |
| CN208836000U (en) * | 2018-09-18 | 2019-05-07 | 广州市特沃能源管理有限公司 | A kind of adjustable DC output circuit |
| CN109495137A (en) * | 2019-01-15 | 2019-03-19 | 广东志成冠军集团有限公司 | A kind of the signal coupled system and method for subsea DC power transmission cable |
| CN212660148U (en) * | 2020-05-20 | 2021-03-05 | 海能达通信股份有限公司 | Voltage-controlled oscillator and frequency generator |
| CN112653455A (en) * | 2020-12-04 | 2021-04-13 | 电子科技大学 | High-frequency low-power-consumption self-mixing millimeter wave voltage-controlled oscillator |
| CN215773545U (en) * | 2021-08-05 | 2022-02-08 | 东莞凯韵科技有限公司 | Direct current servo circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113630688A (en) | 2021-11-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4310383B2 (en) | Differential audio line receiver | |
| CN101790122B (en) | Plosive eliminating circuit of audio system and mobile communication terminal | |
| CN212726952U (en) | Amplifying circuit for converting microphone differential input into single-ended output | |
| CN215773545U (en) | Direct current servo circuit | |
| CN113630688B (en) | Direct current servo circuit | |
| CN103427771B (en) | BTL type differential type audio power amplifying circuit | |
| JP2007006012A (en) | Amplifier and amplification method | |
| CN207219030U (en) | Stero set circuit and audio frequency apparatus | |
| CN104639085A (en) | Low-power filter circuit for weak electrical signals | |
| CN110662128A (en) | Microphone signal amplification system for active noise reduction | |
| CN207369275U (en) | A kind of circuit structure of sound pick-up | |
| CN203563186U (en) | Noise reduction circuit and voice audio driving circuit provided with same | |
| CN202634678U (en) | Noise-reduction circuit | |
| CN105516854A (en) | Signal processing circuit for loudspeaker box | |
| CN217470279U (en) | MEMS system comprising bias circuit of ECM | |
| CN215072884U (en) | Filter circuit for noise reduction earphone | |
| CN219164530U (en) | Underwater sound transducer small signal acquisition low-noise amplifying circuit | |
| CN216313051U (en) | Single-channel double-output audio power amplifier | |
| CN219643916U (en) | Device, system and electronic equipment for transmitting power based on differential signal lines | |
| CN208043927U (en) | The power consumption test device of D class power amplifiers | |
| CN214799872U (en) | Moving coil microphone audio amplification circuit and earphone | |
| CN218335981U (en) | Low-noise audio signal differential-to-single-ended circuit | |
| CN220545132U (en) | Single-direction high-sensitivity vehicle-mounted electret microphone | |
| CN212034314U (en) | Antistatic anti-interference filter circuit module of digital microphone | |
| CN210536925U (en) | Audio processing system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |