CN204334493U - A kind of current foldback circuit of audio frequency amplifier - Google Patents
A kind of current foldback circuit of audio frequency amplifier Download PDFInfo
- Publication number
- CN204334493U CN204334493U CN201520060863.8U CN201520060863U CN204334493U CN 204334493 U CN204334493 U CN 204334493U CN 201520060863 U CN201520060863 U CN 201520060863U CN 204334493 U CN204334493 U CN 204334493U
- Authority
- CN
- China
- Prior art keywords
- resistance
- operational amplifier
- amplifier
- electric capacity
- connects
- 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.)
- Expired - Fee Related
Links
Landscapes
- Amplifiers (AREA)
Abstract
The utility model discloses a kind of current foldback circuit of audio frequency amplifier, comprise the first resistance, second resistance, 3rd resistance, 4th resistance, 5th resistance, 6th resistance, 7th resistance, 8th resistance, 9th resistance, first operational amplifier, second operational amplifier, diode, first electric capacity, second electric capacity, triode, relay and DC power supply, first resistance, second resistance and the 3rd resistance form sample circuit, first operational amplifier and the 4th resistance form amplifying circuit, second operational amplifier, 5th resistance, 6th resistance, 7th resistance, first electric capacity and diode form voltage comparator circuit, triode and relay form control circuit.The current foldback circuit of a kind of audio frequency amplifier described in the utility model, low in energy consumption, fast response time, can react rapidly shutoff amplifier during circuit overcurrent, avoid amplifier loss.
Description
Technical field
The utility model relates to a kind of current foldback circuit of audio frequency amplifier, particularly relates to a kind of current foldback circuit of fast response time low in energy consumption of audio frequency amplifier.
Background technology
Audio frequency power amplifier is audio-frequency power amplifier by name entirely, is for promoting loud speaker sounding, thus the power amplifier device of reproduced sound.Audio-frequency power amplifier is exactly amplify smaller audio signal, its power is increased, then exports.Audio-frequency power amplifier can produce heat when using, and amplifier can be caused to damage, need overcurrent protection during short circuit.At present, the current foldback circuit power consumption of audio frequency amplifier is higher, and response speed is comparatively slow, can not turn off amplifier in time.
Utility model content
The purpose of this utility model is just the current foldback circuit of the fast response time low in energy consumption providing a kind of audio frequency amplifier in order to solve the problem.
The utility model is achieved through the following technical solutions above-mentioned purpose:
The current foldback circuit of a kind of audio frequency amplifier described in the utility model, comprises the first resistance, second resistance, 3rd resistance, 4th resistance, 5th resistance, 6th resistance, 7th resistance, 8th resistance, 9th resistance, first operational amplifier, second operational amplifier, diode, first electric capacity, second electric capacity, triode, relay and DC power supply, the first end of described first resistance is connected with the first end of described second resistance and as the first sampled signal input of described current foldback circuit, second end of described first resistance is connected with the first end of described 3rd resistance and as the second sampled signal input of described current foldback circuit, the second end of described second resistance simultaneously with the first end of described 4th resistance, the inverting input of described first operational amplifier connects, the second end of described 3rd resistance simultaneously with the first end of described 5th resistance, the in-phase input end of described first operational amplifier connects, the output of described first operational amplifier simultaneously with the second end of described 4th resistance, the positive pole of described diode connects, the negative pole of described diode simultaneously with the first end of described 6th resistance, the first end of described first electric capacity, the in-phase input end of described second operational amplifier connects, the output of described second operational amplifier simultaneously with the first end of described 7th resistance, the first end of described 8th resistance connects, second end of described 8th resistance is connected with the base stage of described triode, the collector electrode of described triode is connected with the first end of described relay, the positive pole of described DC power supply simultaneously with the power positive end of described first operational amplifier, the power positive end of described second operational amplifier, the first end of described 9th resistance, the first end of described second electric capacity, second end of described relay connects, the negative pole of described DC power supply simultaneously with the second end of described 5th resistance, second end of described 6th resistance, second end of described first electric capacity, second end of described 7th resistance, the inverting input of described first operational amplifier, the power-of described second operational amplifier extremely connects, and the normally-closed contact of described relay is connected with the power input of described audio frequency amplifier.
The beneficial effects of the utility model are:
The current foldback circuit of a kind of audio frequency amplifier described in the utility model, low in energy consumption, fast response time, can react rapidly shutoff amplifier during circuit overcurrent, avoid amplifier loss.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of the current foldback circuit of a kind of audio frequency amplifier described in the utility model.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in further detail:
As shown in Figure 1, the current foldback circuit of a kind of audio frequency amplifier described in the utility model, comprises the first resistance R1, second resistance R2, 3rd resistance R3, 4th resistance R4, 5th resistance R5, 6th resistance R6, 7th resistance R7, 8th resistance R8, 9th resistance R9, first operational amplifier A 1, second operational amplifier A 2, diode D, first electric capacity C1, second electric capacity C2, triode Q, relay K and DC power supply Vcc, the first end of the first resistance R1 is connected with the first end of the second resistance R2 and as the first sampled signal input (not marking in figure) of current foldback circuit, second end of the first resistance R1 is connected with the first end of the 3rd resistance R2 and as the second sampled signal input (not marking in figure) of current foldback circuit, second end of the second resistance R2 simultaneously with the first end of the 4th resistance R4, the inverting input of the first operational amplifier A 1 connects, second end of the 3rd resistance R3 simultaneously with the first end of the 5th resistance R5, the in-phase input end of the first operational amplifier A 1 connects, the output of the first operational amplifier A 1 simultaneously with second end of the 4th resistance R4, the positive pole of diode D connects, the negative pole of diode D simultaneously with the first end of the 6th resistance R6, the first end of the first electric capacity C1, the in-phase input end of the second operational amplifier A 2 connects, the output of the second operational amplifier A 2 simultaneously with the first end of the 7th resistance R7, the first end of the 8th resistance R8 connects, and second end of the 8th resistance R8 is connected with the base stage of triode Q, and the collector electrode of triode Q is connected with the first end of relay K, with the power positive end of the first operational amplifier A 1 while of the positive pole of DC power supply Vcc, the power positive end of the second operational amplifier A 2, the first end of the 9th resistance R9, the first end of the second electric capacity C2, second end of relay K connects, the negative pole of DC power supply Vcc simultaneously with second end of the 5th resistance R5, second end of the 6th resistance R6, second end of the first electric capacity C1, second end of the 7th resistance R7, the inverting input of the first operational amplifier A 1, the power-of the second operational amplifier A 2 extremely connects, and the normally-closed contact K-1 of relay K is connected with the power input of audio frequency amplifier.
The current foldback circuit of a kind of audio frequency amplifier described in the utility model; first resistance R1, the second resistance R2 and the 3rd resistance R3 form sample circuit; first operational amplifier A 1 and the 4th resistance R4 form amplifying circuit; second operational amplifier A 2, the 5th resistance R5, the 6th resistance R6, the 7th resistance R7, the first electric capacity C1 and diode D form voltage comparator circuit, and triode Q and relay K form control circuit.The sampled signal input Ui of this current foldback circuit is connected with the output of audio frequency amplifier; the voltage signal that sample circuit is taked; amplify through amplifying circuit and convert single-ended signal to, input voltage comparison circuit compares with reference voltage, once overcurrent; second operational amplifier A 2 exports high level; triode Q conducting, relay K adhesive, the normally-closed contact K-1 of relay disconnects; cut off amplifier power supply, reach the object of protection.
Claims (1)
1. a current foldback circuit for audio frequency amplifier, is characterized in that: comprise the first resistance, second resistance, 3rd resistance, 4th resistance, 5th resistance, 6th resistance, 7th resistance, 8th resistance, 9th resistance, first operational amplifier, second operational amplifier, diode, first electric capacity, second electric capacity, triode, relay and DC power supply, the first end of described first resistance is connected with the first end of described second resistance and as the first sampled signal input of described current foldback circuit, second end of described first resistance is connected with the first end of described 3rd resistance and as the second sampled signal input of described current foldback circuit, the second end of described second resistance simultaneously with the first end of described 4th resistance, the inverting input of described first operational amplifier connects, the second end of described 3rd resistance simultaneously with the first end of described 5th resistance, the in-phase input end of described first operational amplifier connects, the output of described first operational amplifier simultaneously with the second end of described 4th resistance, the positive pole of described diode connects, the negative pole of described diode simultaneously with the first end of described 6th resistance, the first end of described first electric capacity, the in-phase input end of described second operational amplifier connects, the output of described second operational amplifier simultaneously with the first end of described 7th resistance, the first end of described 8th resistance connects, second end of described 8th resistance is connected with the base stage of described triode, the collector electrode of described triode is connected with the first end of described relay, the positive pole of described DC power supply simultaneously with the power positive end of described first operational amplifier, the power positive end of described second operational amplifier, the first end of described 9th resistance, the first end of described second electric capacity, second end of described relay connects, the negative pole of described DC power supply simultaneously with the second end of described 5th resistance, second end of described 6th resistance, second end of described first electric capacity, second end of described 7th resistance, the inverting input of described first operational amplifier, the power-of described second operational amplifier extremely connects, and the normally-closed contact of described relay is connected with the power input of described audio frequency amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520060863.8U CN204334493U (en) | 2015-01-28 | 2015-01-28 | A kind of current foldback circuit of audio frequency amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520060863.8U CN204334493U (en) | 2015-01-28 | 2015-01-28 | A kind of current foldback circuit of audio frequency amplifier |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204334493U true CN204334493U (en) | 2015-05-13 |
Family
ID=53170800
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201520060863.8U Expired - Fee Related CN204334493U (en) | 2015-01-28 | 2015-01-28 | A kind of current foldback circuit of audio frequency amplifier |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204334493U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105932636A (en) * | 2016-06-13 | 2016-09-07 | 国家电网公司 | Overcurrent protection circuit of power-frequency withstand voltage test |
-
2015
- 2015-01-28 CN CN201520060863.8U patent/CN204334493U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105932636A (en) * | 2016-06-13 | 2016-09-07 | 国家电网公司 | Overcurrent protection circuit of power-frequency withstand voltage test |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204131691U (en) | A kind of can the bluetooth earphone of automatic switching | |
| CN204334493U (en) | A kind of current foldback circuit of audio frequency amplifier | |
| CN203563019U (en) | Power amplification circuit for loudspeaker box loudspeaker | |
| CN205178996U (en) | Audio signal amplifier circuit | |
| CN204334691U (en) | The two-in-one commutation circuit of a kind of earpiece loudspeaker | |
| CN203618113U (en) | Audio signal clipping control circuit device with power supply correlation | |
| CN203225871U (en) | Simplified audio frequency amplification circuit | |
| CN202649296U (en) | Speech warning circuit of DC power source | |
| CN204439729U (en) | A kind of examination hall communication apparatus detector circuit | |
| CN104682889A (en) | Over-temperature protection circuit for loudspeaker box power amplifier | |
| CN204244181U (en) | The amplifying circuit of analog signal of radiofrequency signal | |
| CN204362002U (en) | A kind of digital audio frequency power amplifier | |
| CN204244250U (en) | A kind of mobile phone signal detector being applied to examination hall | |
| CN204168480U (en) | Digital power amplifier circuit | |
| CN204795566U (en) | Stereo set circuit | |
| CN204190739U (en) | A kind of serial ports level automatic alarm system based on VFO buffer amplifier | |
| CN203423793U (en) | Class-D power amplifier regulation circuit | |
| CN204697277U (en) | The sound control circuit that a kind of USB powers | |
| CN105554672A (en) | Electronic hearing aid device for the old aged | |
| CN201995116U (en) | Sound card control circuit | |
| CN105491497A (en) | Hearing-aid instrument for hearing impairment | |
| CN203563015U (en) | Novel power amplifier for mobile phone | |
| CN203984652U (en) | Power amplifier amplitude limiter circuit | |
| CN204190709U (en) | Based on the amplifier circuit of bias current sources | |
| CN203691615U (en) | Mute circuit of single power supply audio device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150513 Termination date: 20160128 |
|
| EXPY | Termination of patent right or utility model |