CN114727450A

CN114727450A - LED lamp detection circuit and LED lamp driving system

Info

Publication number: CN114727450A
Application number: CN202210289790.4A
Authority: CN
Inventors: 吴哲玮
Original assignee: Xiamen Lingyang Huaxin Technology Co ltd
Current assignee: Xiamen Lingyang Huaxin Technology Co ltd
Priority date: 2022-03-23
Filing date: 2022-03-23
Publication date: 2022-07-08

Abstract

The invention discloses an LED lamp detection circuit, relates to the field of LED lamp control, and is mainly used for detecting LED lamps. The LED lamp detection circuit comprises a first power supply and a second power supply and is used for detecting the LED lamp. The first power supply outputs a first voltage, the second power supply outputs a second voltage, the first voltage is greater than the second voltage, and the difference value between the first voltage and the second voltage is greater than the conduction voltage of the LED lamp, so that the LED lamp can be lightened. Therefore, the detection of the LED lamp can be realized through the first power supply and the second power supply under the condition that the driving chip is not used, the condition that the detection of the LED lamp is not correct due to the fact that the driving chip is abnormal is avoided, and the accuracy and the reliability of detection of the LED lamp are improved. The invention also provides an LED lamp driving system which has the same beneficial effects as the LED lamp detection circuit.

Description

LED lamp detection circuit and LED lamp driving system

Technical Field

The invention relates to the field of LED lamp detection, in particular to an LED lamp detection circuit and an LED lamp driving system.

Background

In the prior art, a driving chip is connected to an LED (Light-Emitting Diode) lamp to drive the LED lamp, and at this time, if it is necessary to detect whether the LED lamp is abnormal, the method includes: and controlling the driving chip to output different driving currents so that the LED lamp works with different luminous efficiencies, and judging whether the LED lamp can work normally or not.

However, when the light emission efficiency of the LED lamp does not correspond to the driving current output by the driving chip, the LED lamp may be abnormal, and the driving chip may be abnormal. That is, the method in the prior art cannot accurately determine whether the LED lamp is abnormal.

Disclosure of Invention

The invention aims to provide an LED lamp detection circuit and an LED lamp driving system, which can realize detection of an LED lamp under the condition of not using a driving chip, avoid the condition of LED lamp detection error caused by driving chip abnormity, and improve the accuracy and reliability of LED lamp detection.

In order to solve the above technical problem, the present invention provides an LED lamp detection circuit, including:

the first power supply is connected with the first end of the LED lamp at the output end and used for outputting first voltage when the LED lamp is detected;

the output end of the second power supply is respectively connected with the second end of the LED lamp and the output end of the driving chip and used for outputting a second voltage when the LED lamp is detected;

the first voltage is greater than the second voltage, and the difference between the first voltage and the second voltage is not less than the working voltage of the LED lamp.

Preferably, the method further comprises the following steps:

and the switching circuit is used for switching on the LED lamp during detection, and has one end connected with the output end of the second power supply and the other end connected with the output end of the driving chip.

Preferably, the LED lamp is multiple;

the switch circuits are multiple and correspond to the LED lamps one by one.

Preferably, the switching circuit is a diode;

and the cathode of the diode is connected with the output end of the second power supply, and the anode of the diode is connected with the output end of the driving chip.

Preferably, the switching circuit is a transistor;

and the first end and the control end of the transistor are both connected with the output end of the second power supply, and the second end of the transistor is connected with the output end of the driving chip.

Preferably, the transistor is a P-channel metal oxide semiconductor (PMOS);

the grid electrode of the PMOS is the control end of the transistor, one of the source electrode and the drain electrode of the PMOS is the first end of the transistor, and the other one is the second end of the transistor.

Preferably, the second voltage is a power supply voltage of the driving chip;

and the second end of the LED lamp and the output end of the driving chip are connected with the power end of the driving chip through the switch circuit.

Preferably, the second voltage is a constant value or a fluctuating value.

In order to solve the technical problem, the invention also provides an LED lamp system which comprises the LED lamp detection circuit, a driving chip and an LED lamp.

The application provides a LED lamp detection circuit, including first power and second power, when detecting the LED lamp. The first power supply outputs a first voltage, the second power supply outputs a second voltage, the first voltage is greater than the second voltage, and the difference between the first voltage and the second voltage is greater than the conduction voltage of the LED lamp, so that the LED lamp can be lightened. Therefore, the detection of the LED lamp can be realized through the first power supply and the second power supply under the condition that the driving chip is not used, the condition that the detection of the LED lamp is not correct due to the fact that the driving chip is abnormal is avoided, and the accuracy and the reliability of detection of the LED lamp are improved.

The invention also provides an LED lamp driving system which has the same beneficial effects as the LED lamp detection circuit.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a block diagram of a detection circuit for an LED lamp according to the present invention;

fig. 2 is a specific structural block diagram of an LED lamp detection circuit provided in the present invention;

FIG. 3 is a schematic diagram of a power output provided by the present invention;

FIG. 4 is a schematic diagram of another power output provided by the present invention;

fig. 5 is a schematic diagram of a first specific implementation of the LED lamp detection circuit provided in the present invention;

FIG. 6 is a schematic diagram of a second exemplary LED lamp detection circuit according to the present invention;

fig. 7 is a schematic diagram of a third specific implementation of the LED lamp detection circuit provided in the present invention.

Detailed Description

The core of the invention is to provide the LED lamp detection circuit and the LED lamp driving system, which can realize the detection of the LED lamp under the condition of not using a driving chip, avoid the condition of LED lamp detection error caused by the abnormality of the driving chip and improve the accuracy and the reliability of the detection of the LED lamp.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a block diagram of a structure of a detection circuit for an LED lamp provided in the present invention, the circuit includes:

the first power supply 12 with an output end connected with the first end of the LED lamp is used for outputting a first voltage when the LED lamp is detected;

the second power supply 13 is connected with the second end of the LED lamp and the output end of the driving chip 11 at the output end respectively, and is used for outputting a second voltage when the LED lamp is detected;

Specifically, in the present application, when the LED lamp is connected to the driving chip 11, two ends of the LED lamp are respectively provided with a power supply, that is, the first power supply 12 and the second power supply 13 described above, and then when the LED lamp needs to be detected, the first power supply 12 is controlled to output the first voltage, and the second power supply 13 is controlled to output the second voltage, so that even if the LED lamp is connected to the driving chip 11, the detection of the LED lamp without using the driving chip 11 can be realized.

The first voltage is greater than the second voltage, the first power supply 12 is specifically connected with the anode of the LED lamp, the second power supply 13 is specifically connected with the cathode of the LED lamp, and the difference value between the first voltage and the second voltage is greater than the voltage of the LED lamp, so that when the LED lamp is detected, the LED lamp can be normally lightened due to the pressure difference between the first voltage and the second voltage, at the moment, the LED lamp can be normally used, otherwise, the LED lamp is abnormal and cannot be normally used.

Referring to fig. 2, fig. 2 is a specific structural block diagram of an LED lamp detection circuit according to the present invention.

As a preferred embodiment, the second voltage is a power supply voltage of the driving chip;

the second end of the LED lamp and the output end of the driving chip 11 are connected to the power end of the driving chip 11 through a switch circuit.

Further, in order to reduce the cost of the circuit, reduce the use of power module as far as possible, the second voltage here can choose for use driver chip's mains voltage, specifically, can but not be limited to be connected with the power end on driver chip 11, then when needing to detect the LED lamp, the first voltage of the first power of direct control 12 output can, need not control second power 13 again, also need not additionally set up second power 13 again, can reduce detection circuitry's cost to a certain extent.

In addition, referring to fig. 3 and fig. 4, fig. 3 is a schematic diagram of power output provided by the present invention, and fig. 4 is a schematic diagram of power output provided by the present invention.

In fig. 3 and 4, VDD1 is a first voltage output by the first power supply 12, VDD1 is a second voltage output by the second power supply 13, a time period during which VDD1 is increased corresponds to a time period during which the LED lamp is detected (i.e., LED failure detection), Δ V is a difference between the first voltage and the second voltage, and VDD2 may be a stable voltage value (as in fig. 3) or a floating voltage value (as in fig. 4). As long as reliable conduction of the LED lamp is achieved, the present application is not limited thereto.

In conclusion, the detection of the LED lamp can be realized through the first power supply 12 and the second power supply 13 without using the driving chip 11, the situation of detection error of the LED lamp caused by abnormality of the driving chip 11 is avoided, and the accuracy and reliability of detection of the LED lamp are improved.

On the basis of the above-described embodiment:

as a preferred embodiment, the method further comprises the following steps:

and the switching circuit is connected with the output end of the second power supply 13 at one end and connected with the output end of the driving chip 11 at the other end, and is used for conducting when the LED lamp is detected.

Specifically, a switch circuit is further arranged between the output end of the driving chip 11 and the second power supply 13, the switch circuit is switched on when the LED lamp is required to be detected, and the switch circuit is in a cut-off state when the LED lamp is not detected, so that the driving current output by the driving chip 11 can be prevented from flowing backwards to the second power supply 13, and the influence on the second power supply 13 is prevented.

The switch circuit can be integrated in the driving chip, as shown in fig. 5, at this time, an independent switch circuit and a driving chip are not needed, the size is small, and the use is convenient.

As a preferred embodiment, the LED lamp is plural;

the switch circuits are multiple and correspond to the LED lamps one by one.

When the number of the LED lamps is more than one, the number of the switch circuits is more than one, and the switch circuits correspond to the LED lamps one to one. For example, referring to fig. 5, fig. 6 and fig. 7, fig. 5 is a schematic diagram illustrating a specific implementation of a first LED lamp detection circuit provided by the present invention, and in fig. 5, a switch circuit is integrated in a driving chip, where the driving chip includes a data receiving module, a timing control module and a current source. The data receiving module controls the power source according to the input data signal and the input control signal based on the clock control module, so that the current source outputs corresponding driving current, and the LED lamp is controlled.

Fig. 6 is a schematic diagram of a specific implementation of a second LED lamp detection circuit provided in the present invention, and fig. 7 is a schematic diagram of a specific implementation of a third LED lamp detection circuit provided in the present invention. In each of fig. 5, 6 and 7, three LED lamps, i.e., red (R in the figure), green (G in the figure) and blue (B in the figure), are taken as an example.

As a preferred embodiment, the switching circuit is a diode;

the cathode of the diode is connected to the output terminal of the second power supply 13, and the anode of the diode is connected to the output terminal of the driver chip 11.

The present embodiment aims to provide a specific implementation manner of the switch circuit, specifically, as shown in fig. 7, the switch circuit may be configured as a diode, and by using the unidirectional conduction characteristic of the diode, the diode is turned on to implement the detection of the LED lamp only when the voltage drops of the first voltage and the second voltage output by the first power supply 12 and the second power supply 13 are relatively large.

As a preferred embodiment, the switching circuit is a transistor;

the first end and the control end of the transistor are both connected with the output end of the second power supply 13, and the second end of the transistor is connected with the output end of the driving chip 11.

The present embodiment aims to provide another specific implementation manner of the switch circuit, specifically, as shown in fig. 6, the switch circuit may be, but is not limited to, configured as a transistor, a control terminal is disposed in the transistor, and only when voltage drops of the first voltage and the second voltage output by the first power supply 12 and the second power supply 13, respectively, are large, specifically, when the first voltage is larger than the second voltage, a voltage difference between the control terminal and the second terminal of the transistor is large, and reaches a conducting voltage of the transistor, and the transistor is turned on, thereby implementing detection on the LED lamp.

Therefore, the transistor in the application can realize the function of the switch circuit, and the realization mode is simple and reliable.

As a preferred embodiment, the transistor is a PMOS (positive channel Metal Oxide Semiconductor);

the grid electrode of the PMOS is the control end of the transistor, the drain electrode of the PMOS is the first end of the transistor, and the source electrode of the PMOS is the second end of the transistor.

Specifically, the transistor may be, but not limited to, a PMOS transistor, and the MOS transistor may be either a PMOS (positive channel Metal Oxide Semiconductor) or an NMOS (negative channel Metal Oxide Semiconductor). The parasitic diode in the MOS transistor is mainly applied in the embodiment, specifically, the anode of the parasitic diode is connected with the first power supply, the cathode of the parasitic diode is connected with the second power supply, the parasitic diode is used for realizing the function of the switching circuit, and the realization mode is simple and reliable.

In order to solve the technical problem, the invention further provides an LED lamp system, which comprises the LED lamp detection circuit, a driving chip 11 and an LED lamp.

The driving clock is internally but not limited to comprise an input module, a time sequence control module, a data storage module, an output module and the like, wherein the input module is used for receiving a control signal sent by an upper computer, the time sequence control module is used for generating a time sequence control signal according to the control signal sent by the upper computer, and the output module is used for sending the time sequence control signal to the LED lamp so as to drive the LED lamp.

It is to be noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An LED lamp detection circuit, comprising:

2. The LED lamp detection circuit of claim 1, further comprising:

3. The LED lamp detection circuit of claim 2, wherein the LED lamp is plural;

the switch circuits are multiple and correspond to the LED lamps one by one.

4. The LED lamp detection circuit of claim 2, wherein the switching circuit is a diode;

5. The LED lamp detection circuit of claim 2, wherein the switching circuit is a transistor;

6. The LED light detection circuit of claim 5 wherein the transistor is a P-channel metal oxide semiconductor PMOS;

7. The LED lamp detection circuit of any of claims 2-6, wherein the second voltage is a supply voltage of the driver chip;

8. The LED lamp detection circuit of any of claims 2-6, wherein the second voltage is a constant value or a fluctuating value.

9. An LED lamp driving system, comprising the LED lamp detection circuit as claimed in any one of claims 1 to 8, further comprising a driving chip and an LED lamp.