Photoelectric coupling semiconductor protection device

Abstract

The utility model discloses a photoelectric coupling semiconductor protection device, which is used for power supply protection and comprises a first protection circuit, a second protection circuit and a control circuit, and the first protection circuit and the second protection circuit are respectively and electrically connected with the control circuit. The first protection circuit comprises an input end A, a photoelectric coupler U2, a capacitor C2, a diode D1 and a triode Q1. The input end is electrically connected with the cathode of the photoelectric coupler U2 through a resistor R3. According to the photoelectric coupling semiconductor protection device disclosed by the utility model, the first protection circuit, the second protection circuit and the control circuit are linked, so that different measures are taken for different conditions such as overvoltage, undervoltage and overcurrent of a power supply, and the photoelectric coupling semiconductor protection device has the advantages of stable structure, high safety, high practicability and the like.

Description

Technical Field

[0001] The utility model belongs to the technical field of protection circuits based on photoelectric coupling, and in particular relates to a photoelectric coupling semiconductor protection device. Background Art

[0002] In DCDC power supplies, abnormal conditions such as overvoltage, undervoltage and overcurrent are prone to occur, so protection circuits are needed to protect the power supply. When the above conditions occur, many existing protection circuits are directly disconnected in a one-size-fits-all manner. However, overvoltage and undervoltage are different from overcurrent. Overvoltage and undervoltage need to be able to work again after the abnormality is restored, instead of being unable to automatically resume work like overcurrent.

[0003] Therefore, further improvements are made to the above problems. Utility Model Content

[0004] The main purpose of the utility model is to provide a photoelectrically coupled semiconductor protection device, which is linked through a first protection circuit (when overvoltage, undervoltage, etc. occur), a second protection circuit (when overcurrent, etc. occur) and a control circuit, so as to take different measures for different situations such as overvoltage, undervoltage and overcurrent of the power supply, and has the advantages of stable structure, high safety and high practicality.

[0005] To achieve the above purpose, the utility model provides a photoelectrically coupled semiconductor protection device for power supply protection, comprising a first protection circuit (when overvoltage, undervoltage, etc. occur), a second protection circuit (when overcurrent, etc. occur) and a control circuit, wherein the first protection circuit and the second protection circuit are electrically connected to the control circuit respectively, wherein:

[0006] The first protection circuit includes an input terminal A, a photocoupler U2, a capacitor C2, a diode D1 and a transistor Q1, wherein the input terminal is electrically connected to the cathode of the photocoupler U2 through a resistor R3, the emitter of the photocoupler U2 is electrically connected to the anode of the diode D1 through the capacitor C2, and the emitter of the photocoupler U2 is electrically connected to the base of the transistor Q1 through the resistor R2, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is grounded through the resistor R1, and the two ends of the resistor R1 are connected in parallel with the capacitor C1;

[0007] The second protection circuit includes an input terminal B, a photocoupler U3 and a diode D2, wherein the input terminal B is electrically connected to the cathode of the photocoupler U3 through a resistor R4, and the emitter of the photocoupler U3 is electrically connected to the anode of the diode D2;

[0008] The control circuit includes a control chip U1, a control terminal (pin 16) of the control chip U1 is electrically connected to the cathode of the diode D1 and the cathode of the diode D2, and pin 1 of the control chip U1 is electrically connected.

[0009] As a further preferred technical solution of the above technical solution, the control end of the control chip U1 is also grounded through a resistor R5.

[0010] As a further preferred technical solution of the above technical solution, one end of the capacitor C2 close to the photoelectric coupler U2 is grounded through a resistor R6, and one end of the capacitor C2 close to the diode D1 is grounded through a resistor R7.

[0011] As a further preferred technical solution of the above technical solution, the emitter of the photoelectric coupler U3 is also grounded through a resistor R8.

[0012] As a further preferred technical solution of the above technical solution, pin 12 of the control chip U1 is grounded. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The utility model discloses a circuit diagram of a photoelectrically coupled semiconductor protection device. DETAILED DESCRIPTION

[0014] The following description is used to disclose the utility model so that those skilled in the art can implement the utility model. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the utility model defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the utility model.

[0015] The utility model discloses a photoelectrically coupled semiconductor protection device. The specific embodiments of the utility model are further described below in conjunction with preferred embodiments.

[0016] In the embodiments of the present invention, those skilled in the art note that grounding and the like involved in the present invention may be regarded as prior art.

[0017] Preferred embodiments.

[0018] The utility model discloses a photoelectrically coupled semiconductor protection device for power supply protection, comprising a first protection circuit (when overvoltage, undervoltage, etc. occur), a second protection circuit (when overcurrent, etc. occur) and a control circuit, wherein the first protection circuit and the second protection circuit are electrically connected to the control circuit respectively, wherein:

[0019] The first protection circuit includes an input terminal A, a photocoupler U2, a capacitor C2, a diode D1 and a transistor Q1, wherein the input terminal is electrically connected to the cathode of the photocoupler U2 through a resistor R3, the emitter of the photocoupler U2 is electrically connected to the anode of the diode D1 through the capacitor C2, and the emitter of the photocoupler U2 is electrically connected to the base of the transistor Q1 through the resistor R2, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is grounded through the resistor R1, and the two ends of the resistor R1 are connected in parallel with the capacitor C1;

[0020] The second protection circuit includes an input terminal B, a photocoupler U3 and a diode D2, wherein the input terminal B is electrically connected to the cathode of the photocoupler U3 through a resistor R4, and the emitter of the photocoupler U3 is electrically connected to the anode of the diode D2;

[0021] The control circuit includes a control chip U1, a control terminal (pin 16) of the control chip U1 is electrically connected to the cathode of the diode D1 and the cathode of the diode D2, and pin 1 of the control chip U1 is electrically connected.

[0022] Specifically, the control terminal of the control chip U1 is also grounded through a resistor R5.

[0023] More specifically, one end of the capacitor C2 close to the photocoupler U2 is grounded through a resistor R6 and one end of the capacitor C2 close to the diode D1 is grounded through a resistor R7.

[0024] Furthermore, the emitter of the photocoupler U3 is also grounded via a resistor R8.

[0025] Furthermore, pin 12 of the control chip U1 is grounded.

[0026] For this utility model:

[0027] When overvoltage and undervoltage occur, input is made from the input terminal A, the photocoupler U2 is turned on, and then the diode D1 is turned on, so that the 16th pin of the control chip U1 is at a high level, thereby shutting down the power supply, and the 1st pin of the control chip U1 is electrically connected to the collector of the transistor Q1. When the power supply is shut down, the transistor Q1 is turned on, so that the thyristor switch connected to the control terminal of the control chip U1 is short-circuited. After the overvoltage and undervoltage abnormalities at the input terminal A are restored, the work can be resumed;

[0028] When an overcurrent condition occurs, input is input from the input terminal B, the optocoupler U3 is turned on, and then the diode D2 is turned on, so that the 16th pin of the control chip U1 is a high level, thereby shutting down the power supply, and the power supply cannot resume operation.

[0029] It is worth mentioning that the technical features such as grounding involved in this utility model patent application should be regarded as prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional methods in the field, and should not be regarded as the invention point of this utility model patent. This utility model patent will not be further elaborated.

[0030] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A photoelectrically coupled semiconductor protection device for power supply protection, characterized in that: The invention comprises a first protection circuit, a second protection circuit and a control circuit, wherein the first protection circuit and the second protection circuit are electrically connected to the control circuit respectively, wherein: The first protection circuit includes an input terminal A, a photocoupler U2, a capacitor C2, a diode D1 and a transistor Q1, wherein the input terminal is electrically connected to the cathode of the photocoupler U2 through a resistor R3, the emitter of the photocoupler U2 is electrically connected to the anode of the diode D1 through the capacitor C2, and the emitter of the photocoupler U2 is electrically connected to the base of the transistor Q1 through the resistor R2, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is grounded through the resistor R1, and the two ends of the resistor R1 are connected in parallel with the capacitor C1; The second protection circuit includes an input terminal B, a photocoupler U3 and a diode D2, wherein the input terminal B is electrically connected to the cathode of the photocoupler U3 through a resistor R4, and the emitter of the photocoupler U3 is electrically connected to the anode of the diode D2; The control circuit includes a control chip U1 , a control end of the control chip U1 is electrically connected to the cathode of the diode D1 and the cathode of the diode D2 , and a pin 1 of the control chip U1 is electrically connected.

2. A photoelectrically coupled semiconductor protection device according to claim 1, characterized in that: The control terminal of the control chip U1 is also grounded through a resistor R5.

3. A photoelectrically coupled semiconductor protection device according to claim 2, characterized in that: One end of the capacitor C2 close to the photocoupler U2 is grounded through a resistor R6 , and one end of the capacitor C2 close to the diode D1 is grounded through a resistor R7 .

4. The photoelectrically coupled semiconductor protection device according to claim 3, characterized in that: The emitter of the photocoupler U3 is also grounded via a resistor R8.

5. The photoelectrically coupled semiconductor protection device according to claim 4, characterized in that: Pin 12 of the control chip U1 is grounded.

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