CN218497770U

CN218497770U - LED wide voltage self-adaptive circuit and display device

Info

Publication number: CN218497770U
Application number: CN202222731120.1U
Authority: CN
Inventors: 孙占龙; 梁佩俊; 袁楚卓
Original assignee: Shenzhen Meixi Micro Semiconductor Co ltd
Current assignee: Shenzhen Meisi Micro Semiconductor Co ltd
Priority date: 2022-10-18
Filing date: 2022-10-18
Publication date: 2023-02-17
Anticipated expiration: 2032-10-18

Abstract

The utility model discloses a wide voltage self-adaptation circuit of LED contains LED light-emitting component, constant current drive unit and switch element, LED light-emitting component contain first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3, constant current drive unit contain first constant current drive unit, second constant current drive unit and third constant current drive unit, first constant current drive unit, second constant current drive unit and third constant current drive unit be connected respectively first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3's negative pole, the utility model discloses can be according to the quantity and the order that power supply voltage's size automatic adjustment R color lamp pearl, G color lamp pearl and B color lamp pearl lighted to make LED light-emitting component adaptation power supply voltage lower not influence normal work, great increase many LED light-emitting component's the voltage width that can normally work.

Description

LED wide voltage self-adaptive circuit and display device

Technical Field

The utility model relates to a LED control technology field especially relates to a wide voltage self-adaptation circuit of LED and display device.

Background

The LED display device is composed of multiple groups of LED light emitting components, and the LED light emitting components in the prior art mostly adopt RGB color mode to perform color modulation, that is, various colors are obtained by changing three color lamp beads of red (R), green (G) and blue (B) and superimposing them on each other.

Typically, these LED lighting assemblies are connected together in parallel. However, as the number of LED lighting assemblies increases or the layout area increases, the load on the circuit increases, which causes voltage attenuation, and ultimately reflects the brightness and color of the LED lighting assemblies. For example, the LED light emitting component close to the voltage source has high brightness and good color performance, and the LED light emitting component far away from the voltage source has low brightness and distorted color performance.

In the prior art, a common method for solving the above technical problems is to increase the power supply voltage so as to ensure that the voltage value of the farthest LED light-emitting component is within the normal working range.

SUMMERY OF THE UTILITY MODEL

The not enough of prior art more than, the utility model discloses a two kinds of technical scheme, the effectual solution leads to keeping away from the not enough problem of LED light emitting component voltage of voltage end because of the wire extension produces the voltage partial pressure. A technical scheme is a wide voltage self-adaptation circuit of LED, and this technical scheme contains a plurality of MOS pipes of specific connection, and the mode of opening and shutting of MOS pipe is different under the different supply voltage to this realizes quantity and order that automatic adjustment R color lamp pearl, G color lamp pearl and B color lamp pearl are lighted, thereby can adapt to lower supply voltage under the condition of guaranteeing LED light-emitting component normal work, has just so realized LED light-emitting component's wide voltage power supply.

A second technical means is the display device according to the first technical means.

The utility model discloses a first technical scheme specifically as follows:

an LED wide voltage self-adaptive circuit comprises an LED light-emitting component, a constant current driving unit and a switch unit.

LED light emitting component contain first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3.

The constant current driving unit is used for providing stable current for the LED light-emitting component and comprises a first constant current driving unit, a second constant current driving unit and a third constant current driving unit, and the first constant current driving unit, the second constant current driving unit and the third constant current driving unit are respectively connected with the cathodes of the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

The switch unit is used for turning on and off the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

Further, the switching unit is an MOS transistor, and the MOS transistor includes a first MOS transistor Q1, a second MOS transistor Q2, and a third MOS transistor Q3.

In the technical scheme, the first MOS tube Q1, the second MOS tube Q2 and the third MOS tube Q3 are connected in series.

Further, the first MOS transistor Q1 is connected in parallel with the first color lamp bead D1 and is configured to control on/off of the first color lamp bead D1.

And the second MOS tube Q2 is connected with the second color lamp bead D2 in parallel and used for controlling the on-off of the second color lamp bead D2.

And the third MOS tube Q3 is connected with a third color lamp bead D3 in parallel and used for controlling the on-off of the third color lamp bead D3.

The grids of the first MOS tube Q1, the second MOS tube Q2 and the third MOS tube Q3 are connected with a PWM signal end of the logic control unit.

In the technical scheme, the constant current driving unit is connected with and controlled by the logic control unit.

The utility model discloses in more excellent technical scheme, the MOS pipe still contain fourth MOS pipe Q4, fifth MOS pipe Q5, sixth MOS pipe Q6 and seventh MOS pipe Q7.

Fourth MOS pipe Q4 set up first MOS pipe Q1 with between the second MOS pipe Q2 and connect first color lamp pearl D1's negative pole with second color lamp pearl D2's positive pole, be used for the switch first color lamp pearl D1 with route between the second color lamp pearl D2.

Fifth MOS pipe Q5 set up second MOS pipe Q2 with connect between the third MOS pipe Q3 second colour lamp pearl D2's negative pole with third colour lamp pearl D3's positive pole, be used for the switch second colour lamp pearl D2 with route between the third colour lamp pearl D3.

And the sixth MOS tube Q6 is arranged between a power supply voltage end and the anode of the second color lamp bead D2 and used for switching a path between the power supply voltage end and the anode of the second color lamp bead D2.

And the seventh MOS tube Q7 is arranged between a power supply voltage end and the anode of the third color lamp bead D3 and used for switching a passage between the power supply voltage end and the anode of the third color lamp bead D3.

And the gates of the fourth MOS transistor Q4, the fifth MOS transistor Q5, the sixth MOS transistor Q6 and the seventh MOS transistor Q7 are connected with a logic control unit.

In a more preferable technical scheme, the MOS transistor further comprises an eighth MOS transistor Q8.

Eighth MOS pipe Q8 connect first color lamp pearl D1's negative pole and third color lamp pearl D3's positive pole, be used for the switch first color lamp pearl D1 with route between third color lamp pearl D3.

Further, first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3 be any one kind of following six kinds of combinations respectively in proper order:

r color lamp beads, G color lamp beads and B color lamp beads;

or G color lamp beads, R color lamp beads and B color lamp beads;

or a B color lamp bead, a G color lamp bead and an R color lamp bead;

or R color lamp beads, B color lamp beads and G color lamp beads;

or G color lamp beads, B color lamp beads and R color lamp beads;

or a B color lamp bead, an R color lamp bead and a G color lamp bead.

A control method comprises the following steps:

acquiring a pulse signal, and starting the pulse signal according to a periodic cycle.

Pulse signal contain first pulse signal, second pulse signal and third pulse signal, first pulse signal control first color lamp pearl D1 bright go out, second pulse signal control second color lamp pearl bright go out D2, third pulse signal control third color lamp pearl D3 bright go out.

And acquiring a switch control signal.

The switch control signal include fourth switch control signal, fifth switch control signal, sixth switch control signal and seventh switch control signal, fourth switch control signal be used for controlling opening and closing of fourth MOS pipe Q4, fifth switch control signal be used for controlling opening and closing of fifth MOS pipe Q5, sixth switch control signal be used for controlling opening and closing of sixth MOS pipe Q6, seventh switch control signal be used for controlling opening and closing of seventh MOS pipe Q7.

And acquiring a constant current control signal.

The constant current control signals comprise a first constant current control signal, a second constant current control signal and a third constant current control signal, the first constant current control signal is used for controlling the opening and closing of the first constant current driving unit, the second constant current control signal is used for controlling the opening and closing of the second constant current driving unit, and the third constant current control signal is used for controlling the opening and closing of the third constant current driving unit.

And acquiring a power supply voltage value.

And configuring the opening combination of the acquired switch control signal and the constant current control signal according to the power supply voltage value.

In the technical scheme, a specific method for configuring the obtained opening combination of the switch control signal and the constant current control signal according to the power supply voltage value comprises the following steps:

when the power supply voltage value is more than or equal to 9V:

the fourth and fifth switch control signals turn on the fourth and fifth MOS transistors Q4 and Q5, and the sixth and seventh switch control signals turn off the sixth and seventh MOS transistors Q6 and Q7.

The third constant current control signal starts the third constant current driving unit, and the first constant current control signal and the second constant current control signal respectively close the first constant current driving unit and the second constant current driving unit.

And under the control of the pulse signal, the third constant current driving unit periodically drives and lights the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

When the voltage value is more than 9V and is more than or equal to 6V:

the fourth and seventh switch control signals turn on the fourth and seventh MOS transistors Q4 and Q7, and the fifth and sixth switch control signals turn off the fifth and sixth MOS transistors Q5 and Q6.

The second constant current control signal and the third constant current control signal respectively start the second constant current driving unit and the third constant current driving unit, and the first constant current control signal closes the first constant current driving unit.

Under the control of the pulse signal, the second constant current driving unit periodically drives and lights the first color lamp bead D1 and the second color lamp bead D2, and the third constant current driving unit periodically drives and lights the third color lamp bead D3.

Or:

the fifth and sixth switching control signals turn on the fifth and sixth MOS transistors Q5 and Q6, and the fourth and seventh switching control signals turn off the fourth and seventh MOS transistors Q4 and Q7.

The first constant current control signal and the third constant current control signal respectively start the first constant current driving unit and the third constant current driving unit, and the second constant current control signal closes the second constant current driving unit.

Under the control of the pulse signal, the first constant current driving unit periodically drives and lights the first color lamp bead D1, and the third constant current driving unit periodically drives and lights the second color lamp bead D2 and the third color lamp bead D3.

When the power supply voltage value is less than 6V:

the sixth switching control signal and the seventh switching control signal turn on the sixth MOS transistor Q6 and the seventh MOS transistor Q7, and simultaneously the fourth switching control signal and the fifth switching control signal turn off the fourth MOS transistor Q4 and the fifth MOS transistor Q5.

The first constant current control signal, the second constant current control signal and the third constant current control signal respectively start the first constant current driving unit, the second constant current driving unit and the third constant current driving unit.

Under the control of the pulse signal, the first constant current driving unit, the second constant current driving unit and the third constant current driving unit respectively periodically drive and light the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

In a more preferable technical scheme, the obtaining of the switch control signal further includes an eighth switch control signal, and the eighth switch control signal is used for controlling on and off of an eighth MOS transistor Q8.

At this time, the method for configuring the switching combination of the acquired switching control signal and the constant current control signal according to the power supply voltage value comprises the following steps:

when the voltage value of the power supply is more than 9V and is more than or equal to 6V, the sixth switching control signal, the seventh switching control signal and the eighth switching control signal respectively turn on the sixth MOS transistor Q6, the seventh MOS transistor Q7 and the eighth MOS transistor Q8, and simultaneously the fourth switching control signal and the fifth switching control signal turn off the fourth MOS transistor Q4 and the fifth MOS transistor Q5.

Under the control of the pulse signal, the second flow driving unit periodically drives and lights the second color lamp bead D2, and the third constant current driving unit periodically drives and lights the first color lamp bead D1 and the third color lamp bead D3.

The second technical scheme of the utility model is for adopting the display device of first technical scheme.

The utility model relates to a wide voltage self-adaptation circuit of LED, control method and display device, this technical scheme can be according to the quantity and the order that supply voltage's size automatic adjustment R look lamp pearl, G look lamp pearl and B look lamp pearl were lighted, make the lower supply voltage of LED light-emitting component adaptation not influence normal work, just so great increase many LED light-emitting component's the voltage width that can normally work. The utility model discloses solved effectively and increased because of LED light emitting component, increased the circuit load and made the power supply voltage decay, finally leaded to LED light emitting component's luminance decay and the problem of color distortion.

Drawings

Fig. 1 is a circuit diagram of an embodiment of a wide voltage adaptive LED circuit.

Fig. 2 is a circuit diagram of another embodiment of an LED wide voltage adaptive circuit.

Fig. 3 is a schematic diagram illustrating a flow of steps in a control method of an LED wide voltage adaptive circuit.

Fig. 4 the utility model relates to a when supply voltage value is greater than or equal to 9V among the wide voltage self-adaptation circuit of LED, first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3's lighting circuit schematic diagram.

FIG. 5 the utility model relates to a 9V > when the supply voltage value is greater than or equal to 6V among the wide voltage self-adaptation circuit of LED, a lighting circuit schematic diagram of first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3.

Fig. 6 the utility model relates to a 9V > when supply voltage value is greater than or equal to 6V among the wide voltage self-adaptation circuit of LED, first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3 another kind of lighting circuit schematic diagram.

Fig. 7 the utility model relates to a when supply voltage < 6V in the wide voltage self-adaptation circuit of LED, first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3's the loop schematic diagram that lights up.

FIG. 8 the utility model relates to a 9V > when the supply voltage value is greater than or equal to 6V among the wide voltage self-adaptation circuit of LED, another kind of lighting circuit schematic diagram of first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3.

Fig. 9 is a timing diagram of the pulse signal and the constant current driving unit when the power supply voltage value is greater than or equal to 9V in the LED wide voltage adaptive circuit.

Fig. 10 is a timing diagram of the pulse signal and the constant current driving unit when the voltage value of the power supply is greater than or equal to 6V in the LED wide voltage adaptive circuit.

Fig. 11 is another timing diagram of the pulse signal and the constant current driving unit when the voltage value of the power supply is greater than or equal to 6V in the LED wide voltage adaptive circuit.

Fig. 12 is a timing diagram of the pulse signal and the constant current driving unit when the power supply voltage in the LED wide voltage adaptive circuit is less than 6V.

Fig. 13 the utility model relates to a 9V > when the supply voltage value is greater than or equal to 6V among the wide voltage self-adaptation circuit of LED, another kind of timing diagram of pulse signal and constant current drive unit.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

For the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; certain well-known structures in the drawings and omissions of their description may be apparent to those skilled in the art. The same or similar reference numerals correspond to the same or similar components.

The prior art LED lighting assemblies are often connected in parallel to form a large area or a long line, but as the area of the LED lighting assembly increases or the length of the LED lighting assembly increases, the load on the line increases, which causes voltage attenuation, and finally reflects the brightness attenuation and color distortion of the LED lighting assembly.

The LED light-emitting component comprises three-color lamp beads, namely an R-color lamp bead (a red lamp bead), a G-color lamp bead (a green lamp bead) and a B-color lamp bead (a blue lamp bead). The working voltage of the R color lamp bead is 2V, the working voltage of the G color lamp bead is 3V, the working voltage of the B color lamp bead is 3V, and the connection modes of the R color lamp bead, the G color lamp bead and the B color lamp bead are usually in series connection. Therefore, under the conventional condition, the LED light-emitting component end can normally work only by adding the power supply voltage above 8V, and the lamp beads with insufficient power supply exist in the R color lamp beads, the G color lamp beads and the B color lamp beads due to the fact that the voltage is lower than 8V, so that the lamp beads with insufficient power supply show brightness attenuation, and are specifically shown in brightness attenuation and color distortion of the whole LED light-emitting component.

The conventional method for solving the above technical problems is to increase the power supply voltage to ensure that the attenuated voltage value of the farthest LED lighting assembly is still within the normal operating range, but in this case, the power supply voltage can only be set within a relatively narrow range and cannot be lower than the voltage threshold of 8V.

The utility model discloses a wide voltage self-adaptation circuit of LED, control method and display device, this technical scheme can the more widened voltage range of adaptation, if supply voltage attenuates to 3.5V, LED light-emitting component still can normally work.

The screen brushing frequency of the LED light-emitting component is kilohertz level, 4K Hz is common, the period of the LED light-emitting component is 0.25ms, the lowest screen brushing frequency which can be recognized by human eyes is 25 Hz, the period of the LED light-emitting component is 40 ms, namely, when the screen brushing period of the light-emitting component is less than 40 ms, the human eyes cannot distinguish the screen brushing period, and the screen brushing period of the LED light-emitting component is far lower than the distinguishing period of the human eyes.

This technical scheme's theory of operation lets R look lamp pearl, G look lamp pearl and B look lamp pearl not light simultaneously at same time point, a lamp pearl can be lighted at least on a time point, like this will allow the lamp pearl that lighting when supply voltage attenuates to 3.5V still can normally work, and the frequency of brushing the screen of lamp pearl is very far above people's naked eye and just distinguishes the frequency, so R look lamp pearl, G look lamp pearl and B look lamp pearl just can light a plurality of circulations in the time that people's naked eye can distinguish, its visual effect and R look lamp pearl, G look lamp pearl and B look lamp pearl are lighted simultaneously with the same time point and are had no difference.

The utility model relates to a wide voltage self-adaptation circuit of LED, control method and display device can light quantity and order according to supply voltage's big or small automatic adjustment R look lamp pearl, G look lamp pearl and B look lamp pearl, makes the lower supply voltage of LED light-emitting component adaptation not influence normal work.

The specific embodiment of the technical scheme is as follows:

example 1

In the embodiment, as shown in fig. 1, an LED wide voltage adaptive circuit includes an LED light emitting device, a constant current driving unit, and a switching unit.

The LED light-emitting component comprises a first color lamp bead D1, a second color lamp bead D2 and a third color lamp bead D3.

The constant current driving unit is used for providing stable current for the LED light-emitting component and comprises a first constant current driving unit L1, a second constant current driving unit L2 and a third constant current driving unit L3.

In this embodiment, the positive electrode of the first color lamp bead D1 is connected to the supply voltage VDD, the negative electrode of the first color lamp bead D1 is connected to the positive electrode of the second color lamp bead D2 and the first constant current driving unit L1, the negative electrode of the second color lamp bead D2 is connected to the positive electrode of the third color lamp bead D3 and the second constant current driving unit L2, and the negative electrode of the third color lamp bead D3 is connected to the third constant current driving unit L3.

In this embodiment, the switch unit is used for turning on and off the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

In a more preferred technical solution of this embodiment, the switching unit is an MOS transistor, and the MOS transistor includes a first MOS transistor Q1, a second MOS transistor Q2, and a third MOS transistor Q3.

It should be noted that the MOS transistor in the present technical solution is a PMOS transistor, and the MOS transistor described in other embodiments may also be an NMOS transistor, and both the embodiment and the drawings are described by way of example as PMOS transistors.

In this embodiment:

the first MOS tube, the second MOS tube and the third MOS tube are connected in series, specifically, a drain electrode of the first MOS tube is connected with a source electrode of the second MOS tube, and a drain electrode of the second MOS tube is connected with a source electrode of the third MOS tube.

The first MOS transistor Q1 is connected in parallel with the first color lamp bead D1 and is configured to control on and off of the first color lamp bead D1, specifically, a source electrode of the first MOS transistor Q1 is connected to an anode of the first color lamp bead D1 and is connected to a power supply voltage VDD, and a drain electrode of the first MOS transistor Q1, a cathode of the first color lamp bead D1, and the first constant current driving unit are connected together.

The second MOS tube Q2 is connected in parallel with the second color lamp bead D2 and is used for controlling the on/off of the second color lamp bead D2, specifically, the source electrode of the second MOS tube Q2 is connected with the positive electrode of the second color lamp bead D2 through the supply voltage VDD, the drain electrode of the second MOS tube Q2 is connected with the negative electrode of the second color lamp bead D2, and the second constant current driving unit is connected together.

And the third MOS tube Q3 is connected with the third color lamp bead D3 in parallel and used for controlling the on-off of the third color lamp bead D3, specifically, the source electrode of the third MOS tube Q3 is connected with the anode of the third color lamp bead D2 by a power supply voltage VDD, the drain electrode of the third MOS tube Q3 and the cathode of the third color lamp bead D3 are connected together, and the third constant current driving unit is connected together.

The gates of the first MOS transistor Q1, the second MOS transistor Q2 and the third MOS transistor Q3 are connected with the PWM signal end of the logic control unit, and the conduction and the closing of the first MOS transistor Q1, the second MOS transistor Q2 and the third MOS transistor Q3 are controlled by the PWM pulse signal. The logic control unit in this embodiment is a common logic control unit in the prior art, and may also be a micro control unit such as an MCU.

In this embodiment, the constant current driving unit is connected to and controlled by the logic control unit.

In a more preferred technical solution of this embodiment, the MOS transistor further includes a fourth MOS transistor Q4, a fifth MOS transistor Q5, a sixth MOS transistor Q6, and a seventh MOS transistor Q7. The fourth MOS transistor Q4, the fifth MOS transistor Q5, the sixth MOS transistor Q6, and the seventh MOS transistor Q7 described below are implemented by taking PMOS transistors as examples.

In this embodiment, specifically, as shown in fig. 1, the fourth MOS transistor Q4 is disposed between the first MOS transistor Q1 and the second MOS transistor Q2, a source of the fourth MOS transistor Q4 is connected to a drain of the first MOS transistor Q1 and a negative electrode of the first color lamp bead D1, and a drain of the fourth MOS transistor Q4 is connected to a source of the second MOS transistor Q2 and a positive electrode of the second color lamp bead D2, and is configured to switch a path between the first color lamp bead D1 and the second color lamp bead D2.

In this embodiment, specifically, fifth MOS pipe Q5 set up second MOS pipe Q2 with between the third MOS pipe Q3, the drain electrode of second MOS pipe Q1 and the negative pole of second colour lamp pearl D1 are connected to fifth MOS pipe Q5's source electrode, third MOS pipe Q2's source electrode and third colour lamp pearl D2's positive pole are connected to fifth MOS pipe Q5's drain electrode, are used for the switch second colour lamp pearl D2 with route between the third colour lamp pearl D3.

In this embodiment, specifically, the source of the sixth MOS transistor Q6 is connected to the supply voltage VDD, and the drain of the sixth MOS transistor Q6 is connected to the positive electrode of the second color lamp bead D2, and is configured to switch a path between the supply voltage end and the positive electrode of the second color lamp bead D2.

In this embodiment, specifically, the source of the seventh MOS transistor Q7 is connected to the power supply voltage VDD, and the drain of the seventh MOS transistor Q7 is connected to the anode of the third color lamp bead D3, and is configured to switch a path between the power supply voltage end and the anode of the third color lamp bead D3.

In this embodiment, the gates of the fourth MOS transistor Q4, the fifth MOS transistor Q5, the sixth MOS transistor Q6 and the seventh MOS transistor Q7 are connected to the logic control unit and controlled by the logic control unit to be turned on and off.

In a more preferred technical solution of this embodiment, the MOS transistor further includes an eighth MOS transistor Q8, as shown in fig. 2.

And the eighth MOS tube Q8 is connected with the negative electrode of the first color lamp bead D1 and the positive electrode of the third color lamp bead D3 and used for switching on and off a passage between the first color lamp bead D1 and the third color lamp bead D3.

One color lamp pearl D1 in this embodiment, second color lamp pearl D2 and third color lamp pearl D3 are R color lamp pearl, G color lamp pearl and B color lamp pearl three-color lamp pearl, specifically, first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3 be any one kind of following six kinds of combinations respectively according to the order:

r color lamp beads, G color lamp beads and B color lamp beads;

or G color lamp beads, R color lamp beads and B color lamp beads;

or a B color lamp bead, a G color lamp bead and an R color lamp bead;

or R color lamp beads, B color lamp beads and G color lamp beads;

or G color lamp beads, B color lamp beads and R color lamp beads;

or a B color lamp bead, an R color lamp bead and a G color lamp bead.

Example 2

This embodiment is a control method applied to embodiment 1, and as shown in fig. 3, the control method includes the following steps:

step S101 acquires a pulse signal, and starts the pulse signal in a periodic cycle.

Pulse signal contain first pulse signal, second pulse signal and third pulse signal, first pulse signal control first color lamp pearl D1 bright go out, second pulse signal control second color lamp pearl bright go out D2, third pulse signal control third color lamp pearl D3 bright go out. In this embodiment, the frequencies of the first pulse signal, the second pulse signal and the third pulse signal are the same.

It should be noted that the first pulse signal, the second pulse signal, and the third pulse signal in this embodiment are PWM pulse signals sent by PWM signal terminals. The first pulse signal is used for controlling the opening and closing of the first MOS transistor Q1, the second pulse signal is used for controlling the opening and closing of the second MOS transistor Q2, and the third pulse signal is used for controlling the opening and closing of the third MOS transistor Q3.

Specifically, the method comprises the following steps:

when the first MOS tube Q1 is turned on under the control of the first pulse signal, the first color lamp bead D1 is not bright; when the first MOS tube Q1 is closed under the control of the first pulse signal, the first color lamp bead D1 is bright.

When the second MOS tube Q2 is turned on under the control of the second pulse signal, the second color lamp bead D2 is not bright; when second MOS pipe Q2 closed under the control of second pulse signal, second color lamp pearl D3 was bright.

When the third MOS tube Q3 is turned on under the control of a third pulse signal, the third color lamp bead D3 is not bright; when third MOS pipe Q3 closed under the control of third pulse signal, third color lamp pearl D3 was bright.

Step S102 acquires a switch control signal.

The switch control signal in step S102 includes a fourth switch control signal, a fifth switch control signal, a sixth switch control signal, and a seventh switch control signal, the fourth switch control signal is used to control the on and off of the fourth MOS transistor Q4, the fifth switch control signal is used to control the on and off of the fifth MOS transistor Q5, the sixth switch control signal is used to control the on and off of the sixth MOS transistor Q6, and the seventh switch control signal is used to control the on and off of the seventh MOS transistor Q7.

Step S103 acquires a constant current control signal.

The constant current control signal in step S103 includes a first constant current control signal, a second constant current control signal, and a third constant current control signal, where the first constant current control signal is used to control the first constant current driving unit L1 to be turned on and turned off, the second constant current control signal is used to control the second constant current driving unit L2 to be turned on and turned off, and the third constant current control signal is used to control the third constant current driving unit L3 to be turned on and turned off.

Step S104 acquires a power supply voltage value.

The step S104 obtains the power supply voltage value to obtain the power supply voltage value of the LED lighting assembly. Taking the plurality of LED light emitting elements connected in parallel as a long line as an example, step S104 obtains a power supply voltage value as a voltage value of each LED light emitting element connected in parallel.

It should be noted that, in this embodiment, specifically, the obtaining of the power supply voltage value may be an automatically collected power supply voltage value, or may also be a voltage interval value in a different length interval calculated according to the lengths of the LED light emitting assemblies connected in parallel, and then the voltage interval value is set. In addition to the above two methods, the present embodiment may also be other methods for acquiring a power supply voltage value, which are commonly known in the prior art, and the description of the present embodiment is omitted here.

And step S105, configuring the opening combination of the switch control signal and the constant current control signal according to the power supply voltage value.

It should be noted that, in this embodiment, step S101, step S102, step S103, step S104 and step S105 are not strictly performed in the order, and the order may be adjusted among some or several steps without affecting the result of the present technical solution.

In this embodiment, the step S105 is divided into three cases, which are respectively specifically:

the first condition is that when the power supply voltage value is more than or equal to 9V:

the fourth and fifth switch control signals turn on the fourth and fifth MOS transistors Q4 and Q5, and the sixth and seventh switch control signals turn off the sixth and seventh MOS transistors Q6 and Q7. At this time, the first MOS transistor Q1 and the second MOS transistor Q2, and the second MOS transistor Q2 and the third MOS transistor Q3 are directly connected together by a wire.

The third constant current control signal turns on the third constant current driving unit L3, and the first constant current control signal and the second constant current control signal respectively turn off the first constant current driving unit L1 and the second constant current driving unit L2.

Under the control of the first pulse signal, the second pulse signal and the third pulse signal, as shown in the timing chart of fig. 9, the third constant current driving unit L3 periodically drives and lights the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3, and the current loop at this time is the current loop 1 in fig. 4.

In the second case, when 9V > power supply voltage value ≧ 6V:

the fourth switching control signal and the seventh switching control signal turn on the fourth MOS transistor Q4 and the seventh MOS transistor Q7, and simultaneously the fifth switching control signal and the sixth switching control signal turn off the fifth MOS transistor Q5 and the sixth MOS transistor Q6. At this time, the first MOS transistor Q1 and the second MOS transistor Q2, and the power supply voltage VDD and the third MOS transistor Q3 are directly connected together by a wire, and the second MOS transistor Q2 and the third MOS transistor Q3 are disconnected.

The second constant current control signal and the third constant current control signal respectively turn on the second constant current driving unit L2 and the third constant current driving unit L3, and the first constant current control signal turns off the first constant current driving unit L1.

In this embodiment, under the control of the first pulse signal, the second pulse signal, and the third pulse signal, as shown in the timing chart of fig. 10, the second constant current driving unit L2 periodically drives and lights the first color lamp bead D1 and the second color lamp bead D2, and the third constant current driving unit L3 periodically drives and lights the third color lamp bead D3, where the current loops at this time are the current loop 2 and the current loop 3 in fig. 5.

Or:

the fifth and sixth switching control signals turn on the fifth and sixth MOS transistors Q5 and Q6, and the fourth and seventh switching control signals turn off the fourth and seventh MOS transistors Q4 and Q7. At this time, the second MOS transistor Q2 and the third MOS transistor Q3 are directly connected together by a wire, and the first MOS transistor Q1 and the second MOS transistor Q2 are disconnected.

The first constant current control signal and the third constant current control signal respectively turn on the first constant current driving unit L1 and the third constant current driving unit L3, and the second constant current control signal turns off the second constant current driving unit L2.

In this embodiment, under the control of the first pulse signal, the second pulse signal and the third pulse signal, as shown in the timing chart of fig. 11, the first constant current driving unit L1 periodically drives and lights the first color lamp bead D1, the third constant current driving unit L3 periodically drives and lights the second color lamp bead D2 and the third color lamp bead D3, and the current loops at this time are the current loop 4 and the current loop 4 in fig. 6.

Third case, i.e. when the supply voltage value < 6V:

the sixth switching control signal and the seventh switching control signal turn on the sixth MOS transistor Q6 and the seventh MOS transistor Q7, and simultaneously the fourth switching control signal and the fifth switching control signal turn off the fourth MOS transistor Q4 and the fifth MOS transistor Q5. At this time, the first MOS transistor Q1 and the second MOS transistor Q2 are disconnected, and the second MOS transistor Q2 and the third MOS transistor Q3 are disconnected. The positive pole lug connection supply voltage VDD of first color lamp pearl D1, second color lamp pearl D2 and third color lamp pearl D3.

The first constant current control signal, the second constant current control signal and the third constant current control signal respectively start the first constant current driving unit L1, the second constant current driving unit L2 and the third constant current driving unit L3.

In this embodiment, under the control of the first pulse signal, the second pulse signal, and the third pulse signal, as shown in the timing chart of fig. 12, the first constant current driving unit L1, the second constant current driving unit L2, and the third constant current driving unit L3 respectively drive and light the first color lamp bead D1, the second color lamp bead D2, and the third color lamp bead D3 periodically, and the current loops at this time are the current loop 6, the current loop 7, and the current loop 8 in fig. 7.

Example 3

The difference between this embodiment and embodiment 2 is that the obtained switch control signal further includes an eighth switch control signal, and the eighth switch control signal is used to control the eighth MOS transistor Q8 to be turned on and off.

In this embodiment, step S105 further includes:

when the voltage value of the power supply is more than 9V and is more than or equal to 6V, the sixth MOS tube Q6, the seventh MOS tube Q7 and the eighth MOS tube Q8 are respectively opened by the sixth switch control signal, the seventh switch control signal and the eighth switch control signal, and meanwhile, the fourth MOS tube Q4 and the fifth MOS tube Q5 are closed by the fourth switch control signal and the fifth switch control signal. At this moment, the first MOS tube Q1 and the second MOS tube Q2 and the third MOS tube Q3 are disconnected, the positive electrodes of the first color lamp bead D1 and the second color lamp bead D2 are directly connected with a power supply voltage VDD, and the positive electrode of the third color lamp bead D3 is connected with the negative electrode of the first color lamp bead D1.

In this embodiment, under the control of the first pulse signal, the second pulse signal, and the third pulse signal, as shown in the timing chart of fig. 13, the second flow driving unit L2 periodically drives to light the second color lamp bead D2, and the third constant current driving unit L3 periodically drives to light the first color lamp bead D1 and the third color lamp bead D3, where the current loops are the current loop 9 and the current loop 10 in fig. 8.

Example 4

This embodiment is a display device using embodiment 1.

The display device comprises a plurality of control circuits disclosed in embodiment 1, and the plurality of control circuits are connected in parallel or in other connection modes to form the display device, such as an LED display screen.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement or improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An LED wide voltage self-adaptive circuit is characterized by comprising an LED light-emitting component, a constant current driving unit and a switch unit;

the LED light-emitting component comprises a first color lamp bead D1, a second color lamp bead D2 and a third color lamp bead D3;

the constant current driving unit is used for providing stable current for the LED light-emitting component and comprises a first constant current driving unit, a second constant current driving unit and a third constant current driving unit, and the first constant current driving unit, the second constant current driving unit and the third constant current driving unit are respectively connected with the cathodes of the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3;

the switch unit is used for opening and closing the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3.

2. The LED wide voltage adaptive circuit according to claim 1, wherein the switching unit is a MOS transistor, and the MOS transistor includes a first MOS transistor Q1, a second MOS transistor Q2 and a third MOS transistor Q3;

the first MOS tube Q1, the second MOS tube Q2 and the third MOS tube Q3 are connected in series;

the first MOS tube Q1 is connected with the first color lamp bead D1 in parallel and is used for controlling the on-off of the first color lamp bead D1;

the second MOS tube Q2 is connected with the second color lamp bead D2 in parallel and used for controlling the on-off of the second color lamp bead D2;

the third MOS tube Q3 is connected with a third color lamp bead D3 in parallel and is used for controlling the on-off of the third color lamp bead D3;

the grid electrodes of the first MOS tube Q1, the second MOS tube Q2 and the third MOS tube Q3 are connected with the PWM signal end of the logic control unit;

and the constant current driving unit is connected with the control end of the logic control unit.

3. The LED wide voltage adaptive circuit according to claim 2, wherein said MOS transistors further comprise a fourth MOS transistor Q4, a fifth MOS transistor Q5, a sixth MOS transistor Q6 and a seventh MOS transistor Q7;

the fourth MOS tube Q4 is arranged between the first MOS tube Q1 and the second MOS tube Q2, and is connected to the negative electrode of the first color lamp bead D1 and the positive electrode of the second color lamp bead D2, and is used for switching a path between the first color lamp bead D1 and the second color lamp bead D2;

the fifth MOS tube Q5 is arranged between the second MOS tube Q2 and the third MOS tube Q3, and is connected to the negative electrode of the second color lamp bead D2 and the positive electrode of the third color lamp bead D3, for switching a path between the second color lamp bead D2 and the third color lamp bead D3;

the sixth MOS tube Q6 is arranged between a power supply voltage end and the anode of the second color lamp bead D2 and used for switching a path between the power supply voltage end and the anode of the second color lamp bead D2;

the seventh MOS transistor Q7 is arranged between a power supply voltage end and the anode of the third color lamp bead D3, and is configured to switch a path between the power supply voltage end and the anode of the third color lamp bead D3;

and the grids of the fourth MOS tube Q4, the fifth MOS tube Q5, the sixth MOS tube Q6 and the seventh MOS tube Q7 are connected with a logic control unit.

4. The LED wide voltage adaptive circuit according to claim 3, wherein said MOS transistor further comprises an eighth MOS transistor Q8;

5. The LED wide voltage adaptive circuit according to claim 1, wherein the first color lamp bead D1, the second color lamp bead D2 and the third color lamp bead D3 are respectively any one of the following six combinations:

r color lamp beads, G color lamp beads and B color lamp beads;

or G color lamp beads, R color lamp beads and B color lamp beads;

or a B color lamp bead, a G color lamp bead and an R color lamp bead;

or R color lamp beads, B color lamp beads and G color lamp beads;

or G color lamp beads, B color lamp beads and R color lamp beads;

or a B color lamp bead, an R color lamp bead and a G color lamp bead.

6. A display device comprising the LED wide voltage adaptive circuit according to any one of claims 1 to 5.