CN103840777A - Operational amplifier input port protective circuit - Google Patents
Operational amplifier input port protective circuit Download PDFInfo
- Publication number
- CN103840777A CN103840777A CN201210489211.7A CN201210489211A CN103840777A CN 103840777 A CN103840777 A CN 103840777A CN 201210489211 A CN201210489211 A CN 201210489211A CN 103840777 A CN103840777 A CN 103840777A
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- China
- Prior art keywords
- diode
- input port
- amplifier input
- operational amplifier
- phase end
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Abstract
The invention relates to an operational amplifier input port protective circuit. A diode D1 and a diode D2 which are reversely connected in parallel are connected to the same-phase end and the opposite-phase end of the operational amplifier input port protective circuit, the positive electrode of the diode D1 is connected with the opposite-phase end, the negative electrode of the diode D1 is connected with the same-phase end, the negative electrode of the diode D2 is connected with the opposite-phase end, and the positive electrode of the diode D2 is connected with the same-phase end. By means of the operational amplifier input port protective circuit, the volt characteristics of the diodes are adopted, the differential pressure is 0.7 V after electrification, a high voltage is kept through a diode clamp, and an operational amplifier input port is protected.
Description
Technical field
The present invention relates to the applied technical field of amplifier, particularly a kind of amplifier input port protection circuit.
Background technology
General amplifier input is not connected to any protection, and its shortcoming is in circuit, if prime output has a little amplifier input terminal voltage rated value that extremely exceedes, can cause amplifier to be burnt or amplifier performance change.
Summary of the invention
In order to overcome above-mentioned the deficiencies in the prior art, the object of the present invention is to provide a kind of amplifier input port protection circuit, utilize the characteristic of diode, after conducting, voltage stabilization is within the specific limits.
To achieve these goals, the technical solution used in the present invention is:
A kind of amplifier input port protection circuit, is connected to diode D1 and the diode D2 of reverse parallel connection at its in-phase end and end of oppisite phase, the anode of diode D1 connects backward end, and negative electrode connects in-phase end, and the negative electrode of diode D2 connects end of oppisite phase, and anode connects in-phase end.
Compared with prior art, the present invention utilizes the volt of diode to press characteristic, and after conducting, pressure reduction, at 0.7V, uses diode clamp to live high voltage, the input port of protection amplifier.
Brief description of the drawings
Accompanying drawing is structural representation of the present invention.
Embodiment
Below in conjunction with drawings and Examples, the present invention is carried out to more detailed explanation.
As shown in the figure; the present invention is a kind of amplifier input port protection circuit; this amplifier is dual power supply amplifier; signal inputs to in-phase end after resistance R 1, and backward end passes through R2 ground connection of point, and in-phase end and end of oppisite phase are connected to diode D1 and the diode D2 of reverse parallel connection; the anode of diode D1 connects backward end; negative electrode connects in-phase end, and the negative electrode of diode D2 connects end of oppisite phase, and anode connects in-phase end.
When adopting when this structure, can see, in the time that the Vin+ of input and the pressure reduction of Vin-are less than 0.7V, diode D1 and D2 cut-off, amplifier input terminal voltage is unaffected, and amplifier is normally worked.
In the time that the Vin+ of input and the pressure reduction of Vin-are greater than 0.7V, diode D1 and D2 conducting, input terminal voltage clamper, at 0.7V, has been protected input port.Ensure the reliability application of amplifier.
Claims (1)
1. an amplifier input port protection circuit, is characterized in that, is connected to diode D1 and the diode D2 of reverse parallel connection at its in-phase end and end of oppisite phase; the anode of diode D1 connects backward end; negative electrode connects in-phase end, and the negative electrode of diode D2 connects end of oppisite phase, and anode connects in-phase end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210489211.7A CN103840777A (en) | 2012-11-26 | 2012-11-26 | Operational amplifier input port protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210489211.7A CN103840777A (en) | 2012-11-26 | 2012-11-26 | Operational amplifier input port protective circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103840777A true CN103840777A (en) | 2014-06-04 |
Family
ID=50803981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210489211.7A Pending CN103840777A (en) | 2012-11-26 | 2012-11-26 | Operational amplifier input port protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103840777A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108700648A (en) * | 2017-03-29 | 2018-10-23 | 深圳市大疆创新科技有限公司 | A kind of amplifying circuit and laser measuring device for measuring, mobile platform |
-
2012
- 2012-11-26 CN CN201210489211.7A patent/CN103840777A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108700648A (en) * | 2017-03-29 | 2018-10-23 | 深圳市大疆创新科技有限公司 | A kind of amplifying circuit and laser measuring device for measuring, mobile platform |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140604 |