CN218829598U

CN218829598U - Fault feedback circuit with high voltage protection

Info

Publication number: CN218829598U
Application number: CN202223311273.7U
Authority: CN
Inventors: 宋刚
Original assignee: Shanghai Simpleds Lighting Technology Co ltd
Current assignee: Shanghai Simpleds Lighting Technology Co ltd
Priority date: 2022-12-09
Filing date: 2022-12-09
Publication date: 2023-04-07
Anticipated expiration: 2032-12-09

Abstract

The utility model discloses a fault feedback circuit with high-voltage protection, which comprises a triode Q1, a high-voltage protection module, a filtering module and a voltage stabilizing module; the base electrode of the triode Q1 is connected with an external control chip, the collector electrode of the triode Q1 is connected with the positive electrode of a power supply and is also connected with a fault feedback output pin, and the emitter electrode of the triode Q1 is connected with a high-voltage protection module; the high-voltage protection module is respectively connected with the base electrode and the emitting electrode of the triode Q1 and is used for protecting the triode Q1 when a circuit fails; the filtering module is arranged between the triode Q1 and the fault feedback output pin and is used for filtering an input signal of the triode Q1; the voltage stabilizing module is arranged between the triode Q1 and the filtering module and used for stabilizing voltage and outputting stable voltage to the triode Q1. The fault feedback circuit realizes that the triode Q1 can be controlled to be cut off by the high-voltage protection module when the circuit breaks down, thereby ensuring that the triode Q1 is not damaged.

Description

Fault feedback circuit with high voltage protection

Technical Field

The present invention relates to a fault feedback circuit, and more particularly to a fault feedback circuit with high voltage protection.

Background

The conventional fault feedback circuit is generally formed by directly connecting a triode with a fault feedback output circuit, and when the circuit has a fault, the fault feedback output circuit has a high-voltage backward flow phenomenon, so that the triode is damaged due to overhigh voltage or current.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a trouble feedback circuit with high voltage protection, it is used for solving conventional trouble feedback circuit and leads to the triode impaired technical problem easily because of not possessing overcurrent or overvoltage protection function.

In order to achieve the above object, the present invention provides a fault feedback circuit with high voltage protection, which includes a transistor Q1, a high voltage protection module, a filtering module and a voltage stabilizing module;

the base electrode of the triode Q1 is connected with an external control chip, the collector electrode of the triode Q1 is connected with the positive electrode of a power supply and is also connected with a fault feedback output pin, and the emitter electrode of the triode Q1 is connected with a high-voltage protection module;

the high-voltage protection module is respectively connected with the base electrode and the emitting electrode of the triode Q1 and is used for controlling the state of the triode Q1;

the filtering module is arranged between the triode Q1 and the fault feedback output pin and is used for filtering an input signal of the triode Q1;

the voltage stabilizing module is arranged between the triode Q1 and the filtering module and is used for stabilizing voltage and outputting stable voltage to the triode Q1.

In one or more embodiments, the high voltage protection module includes a transistor Q2, a resistor R3, and a resistor R5, a base of the transistor Q2 is connected to a first end of the resistor R3, a collector of the transistor Q2 is connected to an external control chip, and an emitter of the transistor Q2 is grounded;

the second end of the resistor R3 is connected with the first end of the resistor R5, the first end of the resistor R5 is also connected with the emitter of the triode Q1, and the second end of the resistor R5 is grounded.

In one or more embodiments, the high voltage protection module further includes a capacitor C3, the capacitor C3 is connected in parallel with the transistor Q2, and the capacitor C3 is grounded.

In one or more embodiments, a resistor R1 is connected in series between the transistor Q1 and the positive power supply, a first end of the resistor R1 is connected to the collector of the transistor Q1, and a second end of the resistor R1 is connected to the positive power supply.

In one or more embodiments, a resistor R2 is connected in series between the triode Q1 and the fault feedback output pin, a first end of the resistor R2 is connected between a collector of the triode Q1 and a first end of the resistor R1, and a second end of the resistor R2 is connected to the fault feedback output pin.

In one or more embodiments, the filtering module includes a transient diode TVS1, a first end of the transient diode TVS1 is connected to the fault feedback output pin and simultaneously connected to a second end of the resistor R2, and the second end of the transient diode TVS1 is grounded.

In one or more embodiments, the filter module further includes a first filter capacitor C1, and the first filter capacitor C1 is connected in parallel with the transient diode TVS 1.

In one or more embodiments, the filter module further includes a second filter capacitor C2, a first end of the second filter capacitor C2 is connected to the first end of the resistor R2, and is simultaneously connected to the first end of the resistor R1 and the collector of the transistor Q1, and a second end of the second filter capacitor C2 is grounded.

In one or more embodiments, the voltage stabilizing module includes a diode D1, and a cathode of the diode D1 is connected to the first end of the resistor R1 and a collector of the transistor Q1, respectively, and is also connected to the first end of the resistor R2.

In one or more embodiments, the voltage regulation module further includes a resistor R4, a first end of the resistor R4 is connected to the anode of the diode D1, and a second end of the resistor R4 is grounded.

Compared with the prior art, according to the utility model discloses a trouble feedback circuit with high-voltage protection, its break-make state through setting up triode Q2 and controlling triode Q1 realizes that triode Q2 steerable triode Q1 ends when the circuit breaks down to guarantee that triode Q1 is not damaged.

Drawings

Fig. 1 is a schematic structural diagram of a fault feedback circuit with high voltage protection according to an embodiment of the present invention.

Fig. 2 is a circuit diagram of a fault feedback circuit with high voltage protection according to an embodiment of the present invention.

Detailed Description

The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited by the following detailed description.

Throughout the specification and claims, unless explicitly stated otherwise, the term "comprise" or variations such as "comprises" or "comprising", etc., will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.

As shown in fig. 1, the fault feedback circuit with high voltage protection according to an embodiment of the present invention includes a transistor Q1, a high voltage protection module 100, a filtering module 200, and a voltage stabilizing module 300.

As shown in fig. 2, the base of the transistor Q1 is connected to the MCU, the collector of the transistor Q1 is connected to the positive VCC of the power supply and is also connected to the feedback output pin FB-OUT, and the emitter of the transistor Q1 is connected to the high voltage protection module 100. Current can be input to the transistor Q1 from the supply positive VCC or the fault feedback output pin FB-OUT.

In one embodiment, a resistor R1 is connected in series between the transistor Q1 and the positive power supply VCC, and a first end of the resistor R1 is connected to the collector of the transistor Q1 and a second end is connected to the positive power supply VCC. The resistor R1 is a pull-up resistor, and when current is input to the triode Q1 from the power supply anode VCC, the resistor R1 can play a role in limiting current; meanwhile, the resistor R1 is also used for providing a feedback voltage for the fault feedback output pin FB-OUT.

A resistor R2 is connected in series between the triode Q1 and the fault feedback output pin FB-OUT, a first end of the resistor R2 is connected between a collector of the triode Q1 and a first end of the resistor R1, and a second end of the resistor R2 is connected with the fault feedback output pin FB-OUT. When current is input to the triode Q1 from the fault feedback output pin FB-OUT, the resistor R2 can play a role in limiting current.

The high voltage protection module 100 is respectively connected to the base and the emitter of the transistor Q1, and is configured to control the state of the transistor Q1. When the circuit is in failure, the triode Q1 can be controlled to be cut off so as to protect the triode Q1.

In one embodiment, the high voltage protection module 100 includes a transistor Q2, a resistor R3 and a resistor R5, wherein a base of the transistor Q2 is connected to a first end of the resistor R3, a collector of the transistor Q2 is connected to the MCU, and an emitter of the transistor Q2 is grounded. The transistor Q2 is used to control the state of the transistor Q1. During normal work, the input voltage is not enough to drive the triode Q2 to work, at the moment, the triode Q2 is cut off, the triode Q1 is conducted, and the current normally flows through the inside of the triode Q1.

The second end of the resistor R3 is connected with the first end of the resistor R5, the first end of the resistor R5 is also connected with the emitting electrode of the triode Q1, and the second end of the resistor R5 is grounded.

When the resistor R1 or the resistor R2 has a fault, the fault feedback output pin FB-OUT injects high voltage, current in the circuit firstly passes through the resistor R5, so that the voltage of a node between the resistor R5 and the resistor R3 is increased, and a high level signal is input to the base electrode of the triode Q2, so that the triode Q2 is conducted.

After the triode Q2 is conducted, the voltage of the FB-MCU interface of the external control chip is pulled down, a low level signal is input into the base electrode of the triode Q1, and the triode Q1 is cut off. At this time, current cannot flow through the triode Q1 again, so that the triode Q1 is protected from being damaged.

Exemplarily, the resistance value of the resistor R1 may be 10K Ω, the resistance values of the resistor R2 and the resistor R3 may be 1K Ω, and the resistor R5=22r1=220k Ω. When the fault feedback output pin FB-OUT reversely flows high voltage to enable the node voltage of the resistor R5 and the resistor R3 to reach 0.6V-0.66V, the triode Q2 is conducted, so that the triode Q1 is controlled to be cut off, and the triode Q1 is protected from being damaged. Thus, the current through transistor Q1 will be constant within 30mA (0.66V/22.1 Ω).

Further, the high-voltage protection module further comprises a capacitor C3, the capacitor C3 is connected with the triode Q2 in parallel, the capacitor C3 is grounded, and the capacitor C3 is used for filtering the output voltage or current of the triode Q2.

The filtering module 200 is disposed between the transistor Q1 and the fault feedback output pin FB-OUT, and is configured to filter an input signal of the transistor Q1.

In one embodiment, the filter module 200 includes a transient diode TVS1, a first terminal of the transient diode TVS1 is connected to the fault feedback output pin FB-OUT and is also connected to a second terminal of the resistor R2, and the second terminal of the transient diode TVS1 is grounded. The transient diode TVS1 is used for voltage surge protection to protect components in the entire circuit from high voltage surge.

The filter module 200 further includes a first filter capacitor C1, and the first filter capacitor C1 is connected in parallel to the transient diode TVS 1. The first filter capacitor C1 is used for primarily filtering the voltage or current signal output from the fault feedback output pin FB-OUT to the transistor Q1.

The filtering module 200 further includes a second filtering capacitor C2, wherein a first end of the second filtering capacitor C2 is connected to a first end of the resistor R2 and is simultaneously connected to a first end of the resistor R1 and a collector of the transistor Q1, and a second end of the second filtering capacitor C2 is grounded. The first filter capacitor C1 is used for filtering the voltage or current signal output from the fault feedback output pin FB-OUT to the transistor Q1 again.

The voltage stabilizing module 300 is disposed between the transistor Q1 and the filtering module 200, and is used to stabilize the voltage and output a stable voltage to the transistor Q1 at the same time.

In one embodiment, the voltage regulator module 300 includes a diode D1 and a resistor R4, a cathode of the diode D1 is connected to a first end of the resistor R1 and a collector of the transistor Q1, and is also connected to a first end of the resistor R2, an anode of the diode D1 is connected to a first end of the resistor R4, and a second end of the resistor R4 is grounded.

In this embodiment, the type of the diode D1 may be BZX84-B7V5, and the diode D1 may ensure that the voltage entering the transistor Q1 does not exceed 7.5V.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.

Claims

1. A fault feedback circuit with high-voltage protection is characterized by comprising a triode Q1, a high-voltage protection module, a filtering module and a voltage stabilizing module;

the voltage stabilizing module is arranged between the triode Q1 and the filtering module and used for stabilizing voltage and outputting stable voltage to the triode Q1.

2. The fault feedback circuit with high voltage protection as claimed in claim 1, wherein the high voltage protection module comprises a transistor Q2, a resistor R3 and a resistor R5, wherein a base of the transistor Q2 is connected to a first end of the resistor R3, a collector of the transistor Q2 is connected to an external control chip, and an emitter of the transistor Q2 is grounded;

3. The fault feedback circuit with high voltage protection as claimed in claim 2, wherein said high voltage protection module further comprises a capacitor C3, said capacitor C3 is connected in parallel with said transistor Q2, and said capacitor C3 is grounded.

4. The fault feedback circuit with high voltage protection as claimed in claim 1, wherein a resistor R1 is connected in series between said transistor Q1 and the positive power supply, a first end of said resistor R1 is connected to the collector of said transistor Q1, and a second end of said resistor R1 is connected to the positive power supply.

5. The fault feedback circuit with high voltage protection as claimed in claim 4, wherein a resistor R2 is connected in series between said transistor Q1 and the fault feedback output pin, a first end of said resistor R2 is connected between a collector of said transistor Q1 and a first end of said resistor R1, and a second end of said resistor R2 is connected to said fault feedback output pin.

6. The fault feedback circuit with high voltage protection as claimed in claim 5, wherein said filtering module comprises a transient diode TVS1, a first terminal of said transient diode TVS1 is connected to said fault feedback output pin and simultaneously connected to a second terminal of said resistor R2, and a second terminal of said transient diode TVS1 is connected to ground.

7. The fault feedback circuit with high voltage protection as claimed in claim 6, wherein said filtering module further comprises a first filtering capacitor C1, and said first filtering capacitor C1 is connected in parallel with said transient diode TVS 1.

8. The fault feedback circuit with high voltage protection as claimed in claim 5, wherein the filter module further comprises a second filter capacitor C2, a first terminal of the second filter capacitor C2 is connected to the first terminal of the resistor R2 and to the first terminal of the resistor R1 and the collector of the transistor Q1, and a second terminal of the second filter capacitor C2 is grounded.

9. The fault feedback circuit with high voltage protection as claimed in claim 8, wherein the voltage regulator module comprises a diode D1, and the cathode of the diode D1 is connected to the first terminal of the resistor R1 and the collector of the transistor Q1, respectively, and is also connected to the first terminal of the resistor R2.

10. The fault feedback circuit with high voltage protection as claimed in claim 9, wherein the voltage regulator module further comprises a resistor R4, a first end of the resistor R4 is connected to the anode of the diode D1, and a second end of the resistor R4 is grounded.