CN219145001U

CN219145001U - Open-circuit N-1 protection circuit of resistance type circuit

Info

Publication number: CN219145001U
Application number: CN202320022691.XU
Authority: CN
Inventors: 时翀翀; 马红娣
Original assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Current assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Priority date: 2023-01-05
Filing date: 2023-01-05
Publication date: 2023-06-06
Anticipated expiration: 2033-01-05

Abstract

The utility model discloses a circuit breaking N-1 protection circuit of a resistance type circuit, which comprises a plurality of groups of LED working circuits connected in parallel, a plurality of groups of LED circuit breaking detection modules and a group of circuit breaking execution modules, wherein each group of LED working circuits is connected with one group of LED circuit breaking detection modules; the LED open circuit detection module is used for detecting the open circuit state of the LED working loop; and the circuit breaking execution module is used for executing the disconnection of all the LED working circuits when the circuit breaking fault occurs in any group of LED working circuits. Compared with the circuit for realizing the electronic N-1 by using a triode and a linear chip, the circuit structure is simpler, the cost of components is low, the experiment modification is simple, and the circuit is applicable to circuits with more LEDs of the car lamp.

Description

Open-circuit N-1 protection circuit of resistance type circuit

Technical Field

The utility model relates to a circuit breaking N-1 protection circuit of a resistance type circuit, and belongs to the technical field of automobile lamps.

Background

At present, the driving scheme adopted for the LED car lamp in the market is as follows: linear chip, resistive or triode constant current drive modes, and the above drive modes are well established. For small lamp items, where the current demand is not great, a resistor circuit is often used as the drive of the LED. Currently, when a resistor is used as an LED drive, an optical N-1 is generally adopted to meet the requirement of regulations when a plurality of LEDs are connected in series and parallel. The existing solution usually uses a triode and a linear chip to realize the electronic N-1, but the circuit has a complex structure, high cost of components and parts and complex experimental rectification.

Disclosure of Invention

The utility model aims to solve the technical problems of overcoming the defects of the prior art and providing the open-circuit N-1 protection circuit of the resistance type circuit, which has simpler circuit structure, low cost of components and parts and simple experiment rectification compared with the circuit which uses a triode and a linear chip to realize the electronic N-1, and can be suitable for the circuit with more LEDs of the car lamp.

In order to solve the technical problems, the technical scheme of the utility model is as follows:

a circuit breaking N-1 protection circuit of a resistance type circuit comprises a plurality of groups of LED working circuits connected in parallel, a plurality of groups of LED circuit breaking detection modules and a group of circuit breaking execution modules, wherein each group of LED working circuits is connected with one group of LED circuit breaking detection modules;

the LED open circuit detection module is used for detecting the open circuit state of the LED working loop;

and the circuit breaking execution module is used for executing the disconnection of all the LED working circuits when the circuit breaking fault occurs in any group of LED working circuits.

Further, the LED power supply module comprises an input power supply module which is used for providing working voltage for the LED working loop module and providing filtering and reverse connection preventing protection.

Further, the LED working loop comprises an LED light source, an LED driving circuit and a circuit breaking protection circuit, wherein the input end of the LED light source is connected with the output end of the input power supply module, the output end of the LED light source is connected with the input end of the LED driving circuit, and the output end of the LED driving circuit is connected with the circuit breaking protection circuit.

Further, the LED driving circuit is a resistive driving circuit.

Further, the input end of the LED circuit breaking detection module is connected with the output end of the LED light source, the output end of the LED circuit breaking detection module is connected with the input end of the circuit breaking execution module, and the output end of the circuit breaking execution module is connected with the circuit breaking protection circuit.

By adopting the technical scheme, the LED working circuit is provided with working voltage and filtering and reverse connection preventing protection through the input power module, the LED working circuit is subjected to open-circuit detection and judgment through the LED open-circuit detection module, and the operation of disconnecting all the LED working circuits is executed when the LED working circuit breaks down through the open-circuit execution module. The utility model realizes a low-cost control circuit mode under the conditions of realizing functions and meeting LED faults.

Drawings

FIG. 1 is a schematic block diagram of a circuit breaker N-1 protection circuit for a resistive circuit according to the present utility model;

FIG. 2 is a schematic diagram of a circuit breaker N-1 protection circuit of a resistive circuit according to the present utility model;

FIG. 3 is a schematic circuit diagram of an LED open circuit detection module of the present utility model;

FIG. 4 is a schematic circuit diagram of a circuit breaking execution module according to the present utility model;

fig. 5 is a schematic circuit diagram of the circuit breaking protection circuit of the present utility model.

Detailed Description

In order that the utility model may be more readily understood, a more particular description of the utility model will be rendered by reference to specific embodiments that are illustrated in the appended drawings.

As shown in fig. 1 and 2, the present embodiment provides a circuit breaking N-1 protection circuit of a resistive circuit, which includes two groups of parallel LED operating circuits, two groups of LED circuit breaking detection modules, and a group of circuit breaking execution modules, each group of LED operating circuits is connected with a group of LED circuit breaking detection modules, and the two groups of LED circuit breaking detection modules share a group of circuit breaking execution modules.

As shown in fig. 1, the LED working circuit of this embodiment includes an LED light source, an LED driving circuit, and a circuit breaking protection circuit, where an input end of the LED light source is connected to an output end of the input power module, an output end of the LED light source is connected to an input end of the LED driving circuit, and an output end of the LED driving circuit is connected to the circuit breaking protection circuit.

The LED light source, the LED driving circuit and the circuit breaking protection circuit are connected in series to form an LED working loop, and the LED driving circuit is used for driving the LED light source to ensure that the LED light source can work normally.

Taking one set of LED operating circuits as an example: as shown in fig. 2, the LED light source mainly comprises LED lamps connected in series, and in this embodiment, 3 LED lamps including LED1, LED3, and LED5 are connected in series. As shown in fig. 2, the LED driving circuit is a resistive driving circuit, and is composed of resistors R7 to R8 and R11 to R12, and the circuit current is regulated by the resistance values of the resistors R7 to R8 and R11 to R12. As shown in fig. 5, the circuit breaking protection circuit adopts a MOS transistor Q3, the voltage Vgs of the MOS transistor Q3 needs to adjust the resistance values of R4 and R15, and when the LED works normally, the MOS transistor Q3 needs to be in a conducting state.

As shown in fig. 1, the LED open circuit detection module of the present embodiment is configured to detect an open circuit state of an LED operating circuit. The input end of the LED circuit breaking detection module is connected with the output end of the LED light source, the output end of the LED circuit breaking detection module is connected with the input end of the circuit breaking execution module, and the output end of the circuit breaking execution module is connected with the circuit breaking protection circuit. The circuit breaking execution module is used for breaking all the LED working circuits when circuit breaking faults occur in any group of LED working circuits.

As shown in fig. 3, the LED open circuit detection module of the present embodiment includes an NMOS transistor Q1, a resistor R2, a resistor R5, a capacitor C9, and a diode D2. As shown in fig. 4, the circuit breaking execution module of the present embodiment includes an NMOS transistor Q5, a resistor R17, and a capacitor C13.

The grid G of the NMOS tube Q1 is connected with the cathode of the LED light source, the drain D of the NMOS tube Q1 is connected with the anode of the diode D2, the grid G of the NMOS tube Q5 is connected with the cathode of the diode D2, and the drain D is connected with the resistor R2 and the grid G of the NMOS tube Q3.

When the LED lamps all work normally, the Vg of the NMOS tube Q1 is high level, the Vs is low level, the NMOS tube Q1 is conducted, the diode D2 cannot work normally according to the principle of preferential conduction, the Vg of the NMOS tube Q5 is low level, the NMOS tube Q5 cannot be conducted, the resistors R4 and R15 divide the voltage, the Vg of the NMOS tube Q3 is high level, the Vs is low level, the NMOS tube Q3 is conducted, and the LED working circuit works normally.

When one LED is disconnected, vg of the NMOS tube Q1 is low level, vs is low level, at the moment, the NMOS tube Q1 is cut off, the diode D2 works normally, at the moment, vg of the NMOS tube Q5 is high level, vs is low level, the MOS tube Q5 is conducted, at the moment, vg of the MOS tube Q3 is low level, vs is low level, Q3 cannot be conducted, and at the moment, the LED working circuit cannot work normally.

Because the two groups of LED open circuit detection modules share one group of open circuit execution modules, namely the grid electrodes G of the NMOS transistors Q3 and Q4 are connected, the cathodes of the diodes D2 and D3 are connected and connected to the grid electrode G of the MOS transistor Q5. When the LED lamps in any group of LED working loops are broken, the broken circuit execution module can work normally, the NMOS tubes Q3 and Q4 cannot be conducted normally, all the LED lamps are in an off state, and the broken circuit N-1 protection function under the two groups of LED light sources can be realized.

In addition, as shown in fig. 1, the embodiment further includes an input power module, where the input power module is used to provide an operating voltage for the LED operating circuit module and provide filtering and anti-reverse connection protection. As shown in fig. 2, the input power module of the present embodiment includes a transient spike suppression diode T1, ceramic capacitors C1 and C4, a resistor R1, and anti-reflection diodes D1, C1 and C4 as input filter capacitors for filtering EMC interference, wherein the anti-reflection diode D1 is used for preventing damage to the lamp when the power is reversely connected.

The technical problems, technical solutions and advantageous effects solved by the present utility model have been further described in detail in the above-described embodiments, and it should be understood that the above-described embodiments are only illustrative of the present utility model and are not intended to limit the present utility model, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present utility model should be included in the scope of protection of the present utility model.

Claims

1. A circuit breaker N-1 protection circuit of a resistance type circuit is characterized in that: the LED circuit breaker comprises a plurality of groups of LED working circuits connected in parallel, a plurality of groups of LED circuit breaking detection modules and a group of circuit breaking execution modules, wherein each group of LED working circuits is connected with one group of LED circuit breaking detection modules;

2. The open N-1 protection circuit for a resistive circuit of claim 1, wherein: the LED working circuit module further comprises an input power module, wherein the input power module is used for providing working voltage for the LED working circuit module and providing filtering and reverse connection preventing protection.

3. The open N-1 protection circuit of a resistive circuit of claim 2, wherein: the LED working loop comprises an LED light source, an LED driving circuit and a circuit breaking protection circuit, wherein the input end of the LED light source is connected with the output end of the input power supply module, the output end of the LED light source is connected with the input end of the LED driving circuit, and the output end of the LED driving circuit is connected with the circuit breaking protection circuit.

4. A circuit breaker N-1 protection circuit for resistive circuits as claimed in claim 3, wherein: the LED driving circuit is a resistance type driving circuit.

5. A circuit breaker N-1 protection circuit for resistive circuits as claimed in claim 3, wherein: the LED circuit breaking detection device comprises an LED circuit breaking detection module, a circuit breaking protection circuit and a circuit breaking execution module, wherein the input end of the LED circuit breaking detection module is connected with the output end of the LED light source, the output end of the LED circuit breaking detection module is connected with the input end of the circuit breaking execution module, and the output end of the circuit breaking execution module is connected with the circuit breaking protection circuit.