CN111565494B

CN111565494B - LED lamp control circuit and baton

Info

Publication number: CN111565494B
Application number: CN202010660155.3A
Authority: CN
Inventors: 覃俐玲
Original assignee: Shenzhen Aschip Tech Co ltd
Current assignee: Shenzhen Aschip Tech Co ltd
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2020-10-27
Anticipated expiration: 2040-07-10
Also published as: CN111565494A

Abstract

The invention discloses an LED lamp control circuit and a baton, wherein the LED lamp control circuit comprises N LED lamp branches connected in parallel between a power supply input end and a grounding end, and a second switch circuit connected in series between the N LED lamp branches and the power supply input end or between the N LED lamp branches and the grounding end; the PWM signal is output through the main control chip, and the first switch circuit and the second switch circuit are controlled to be switched on and switched off; one of the first switch circuit and the second switch circuit controls the working frequency of the LED lamp, and the other switch circuit is switched on during the starting period of the switch circuit which controls the working frequency of the LED lamp to control the self-on duration, so that the average working current of the LED lamp is controlled; the invention realizes the separate control of the working frequency and the average working current of the LED lamp, and avoids the need of simultaneously adjusting the frequency and the duty ratio of a plurality of paths of PWM signals when simultaneously adjusting the working frequency and the average working current of the LED lamp.

Description

LED lamp control circuit and baton

Technical Field

The invention relates to the technical field of LED lamp driving, in particular to an LED lamp control circuit and a baton.

Background

The LED lamp has wide application prospect as a high-efficiency, environment-friendly, safe and durable lamp source device.

In the prior art, the brightness and the light emitting mode of an LED lamp are controlled by adjusting the duty ratio and the frequency of PWM generally, but when a plurality of LED lamps are required to be driven to make a complex light emitting mode, if the brightness of the plurality of LED lamps is further adjusted, the frequency and the duty ratio of PWM signals are required to be changed simultaneously, the program writing difficulty is high, the debugging is difficult, and the time is long.

For example, when controlling N paths of LED lamps to be turned on in a running water mode, if a smooth optimal display effect is to be achieved, the period and duty ratio of each path of PWM signal need to be controlled to be the same, and high levels are presented in turn and the sum of the duty ratios of the N paths of PWM signals is 100%;

at this time, if the brightness of the LED lamp needs to be further adjusted, the duty ratio of each PWM signal needs to be adjusted, for example, the brightness of the LED lamp needs to be adjusted to be low, and at the same time, the effect of the water lamp needs to be achieved, each PWM signal presents a high level in turn, and under the condition that the period is not changed, the duty ratio remains, that is, a low level exists for a period of time after each PWM signal presents a high level in turn, and at this time, a visual pause exists between the first water lamp loop and the second water lamp loop; in this case, if the smooth flowing water display effect needs to be obtained again, the period needs to be changed, so that the sum of the duty ratios of the N paths of PWM signals is 100%, and thus, the frequency and the duty ratio of the N paths of PWM signals need to be changed at the same time each time the brightness of the N paths of LED lamps is adjusted, and the distribution needs to be balanced, which makes the program difficult to implement.

Disclosure of Invention

The invention mainly aims to provide an LED lamp control circuit, which aims to realize the separate control of the average working current and the working frequency of an LED lamp and avoid the need of simultaneously changing the duty ratios and the frequencies of multiple paths of PWM when the average working current and the working frequency of a plurality of LED lamps are simultaneously controlled.

In order to achieve the above object, the LED lamp control circuit provided by the present invention is used for controlling N LED lamps, and includes:

a power input terminal and a ground terminal;

n LED lamp branches, wherein N is greater than or equal to 1, and the N LED lamp branches are connected between the power supply input end and the grounding end in parallel; each LED lamp branch comprises a first switch circuit and an LED lamp group which are connected in series;

the second switch circuit is connected between the N paths of LED lamp branches and the power supply input end in series, or connected between the N paths of LED lamp branches and the grounding end in series;

the main control chip is used for outputting N paths of first PWM signals, correspondingly controlling the switching frequency of the first switching circuits in the N paths of LED lamp branches so as to control the working frequency of each path of LED lamp set, and outputting a second PWM signal to control the conduction duration of the second switching circuit during the starting period of each first switching circuit so as to control the average working current of the LED lamp set;

or, the controller is configured to output a third PWM signal to control a switching frequency of the second switching circuit to control a working frequency of the LED lamp set, and output N paths of fourth PWM signals to correspondingly control a conduction time of the first switching circuit in the N paths of LED lamp branches during a period when the second switching circuit is turned on, so as to control an average working current of each path of LED lamp set.

Optionally, the LED lamp branch includes a first resistor, a second resistor, a first switching tube, and an LED lamp set; one end of the first resistor is a controlled end of the first switch circuit; the other end of the first resistor is connected with one end of the second resistor, the other end of the second resistor is grounded, one end of the first resistor, which is connected with the second resistor, is connected with the grid electrode of the first switch tube, and the drain electrode of the first switch tube is connected with the cathode of the LED lamp bank; the anode of the LED lamp bank is connected with the power input end, and the source electrode of the first switch tube is connected with the input end of the second switch circuit.

Optionally, the second switch circuit includes a third resistor, a fourth resistor and a second switch tube; one end of the third resistor is a controlled end of the second switch circuit, the other end of the third resistor is interconnected with one end of the fourth resistor, the other end of the fourth resistor is grounded, and one end of the third resistor, which is interconnected with the fourth resistor, is connected with the grid electrode of the second switch tube; the drain electrode of the second switching tube is connected with the N paths of LED lamp branches; the source electrode of the second switch tube is grounded.

Optionally, the second switch circuit further comprises a fifth resistor and a first capacitor; one end of the fifth resistor is connected with the drain electrode of the second switch tube, the other end of the fifth resistor is connected with one end of the first capacitor, and the other end of the first capacitor is connected with the source electrode of the second switch tube.

Optionally, the first switching tube and the second switching tube are both MOS tubes.

Optionally, the LED lamp control circuit further includes a key circuit, the key circuit is connected to the main control chip, and the key circuit is configured to switch and output a plurality of key trigger signals to trigger the main control chip to correspondingly control the switching frequency of the first switch circuit or the second switch circuit, so as to adjust the operating frequency of the LED lamp set.

Optionally, the LED lamp control circuit further comprises:

the environment brightness acquisition device is used for acquiring environment brightness, converting the environment brightness into an electric signal and outputting the electric signal to the main control chip;

the main control chip is further configured to correspondingly control the conduction duration of the first switch circuit or the second switch circuit according to the electrical signal when receiving the electrical signal, so as to adjust the average working current of the LED lamp set.

Optionally, the ambient brightness acquiring device includes a photoresistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, and a third switching tube; one end of the sixth resistor is connected with the input end of the main control chip, the other end of the sixth resistor is connected with one end of the photosensitive resistor, the other end of the photosensitive resistor is connected with the power input end, one end of the sixth resistor, which is connected with the photosensitive resistor, is connected with the seventh resistor, the other end of the seventh resistor is connected with the drain electrode of the third switch tube, one end of the eighth resistor and one end of the ninth resistor are connected, the other end of the eighth resistor is connected with the output end of the main control chip, the other end of the ninth resistor is grounded, one end of the eighth resistor, which is connected with the ninth resistor, is connected with the grid electrode of the third switch tube, and the source electrode of the.

The invention also provides a baton which comprises the LED lamp control circuit.

The LED lamp control circuit comprises N LED lamp branches connected in parallel between a power supply input end and a grounding end, and is characterized in that a second switch circuit is arranged to be connected in series between the N LED lamp branches and the power supply input end or between the N LED lamp branches and the grounding end; the main control chip outputs a PWM signal to control the opening and closing of the first switch circuit and the second switch circuit; one of the first switch circuit and the second switch circuit is used for controlling the working frequency of the LED lamp, and the other switch circuit is used for conducting during the starting period of the switch circuit for controlling the working frequency of the LED lamp and controlling the conducting time of the switch circuit, so that the average working current of the LED lamp is controlled; the invention realizes the separate control of the working frequency and the average working current of the LED lamp, and avoids the need of simultaneously changing the duty ratio and the frequency of a plurality of paths of PWM signals when the working frequency and the average working current of the LED lamp are controlled.

Drawings

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

Fig. 1 is a schematic structural diagram of an embodiment of an LED lamp control circuit according to the present invention;

fig. 2 is a schematic structural diagram of another embodiment of an LED lamp control circuit according to the present invention;

FIG. 3 is a circuit diagram of an embodiment of an LED lamp control circuit according to the present invention;

FIG. 4 is a schematic diagram of an output waveform of a main control chip in an embodiment of an LED lamp control circuit according to the present invention;

fig. 5 is a schematic diagram of an output waveform of a main control chip in another embodiment of the LED lamp control circuit of the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	Master control chip	LDR	Photoresistor
200	LED lamp branch	VCC	Power input terminal
				201	First switch circuit	Q1	First switch tube
300	Second switch circuit	Q2	Second switch tube
				R1	A first resistor	Q3	Third switch tube
R2	Second resistance	R7	Seventh resistor
				R4	Fourth resistor	R8	Eighth resistor
R5	Fifth resistor	R9	Ninth resistor
				R6	Sixth resistor	C1	First capacitor

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

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 only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

If there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The invention provides an LED lamp control circuit which can be applied to various application scenes or products, such as a light-emitting device, a baton and the like.

Referring to fig. 1 to 5, in an embodiment of the present invention, the LED lamp control circuit includes:

a power input terminal VCC and a ground terminal;

n LED lamp branches 200, where N is greater than or equal to 1, and the N LED lamp branches 200 are connected in parallel between the power input terminal VCC and the ground terminal; each path of LED lamp branch 200 includes a first switch circuit 201 and an LED lamp set connected in series;

the second switch circuit 300 is connected in series between the N LED lamp branches 200 and the power input terminal VCC, or connected in series between the N LED lamp branches 200 and the ground terminal;

the main control chip 100 is configured to output N paths of first PWM signals, correspondingly control a switching frequency of the first switch circuit 201 in the N paths of LED lamp branches 200 to control a working frequency of each path of LED lamp set, and output a second PWM signal to control a conducting duration of the second switch circuit 300 during a period when each first switch circuit 201 is turned on, so as to control an average working current of the LED lamp set; or, the controller is configured to output a third PWM signal to control the switching frequency of the second switch circuit 300, so as to control the operating frequency of the LED lamp set, and output N paths of fourth PWM signals, so as to correspondingly control the conducting time of the first switch circuit 201 in the N paths of LED lamp branches 200 during the period when the second switch circuit 300 is turned on, so as to control the average operating current of each path of LED lamp set.

In this embodiment, N is greater than or equal to 1, and as shown in fig. 1 and 2, N LED lamp branches are LED lamp branch 1, LED lamp branch 2, and LED lamp branch N, respectively; not exhaustive of the figures.

The main control chip 100 outputs a second PWM signal to control the on-time of the second switch circuit 300 in the on-time of each first switch circuit 201 during the on-period, which may be a one-time on-time or an accumulation of multiple on-times;

in this embodiment, the fourth PWM signal correspondingly controls the on-time of the first switch circuit 201 in the N LED lamp branches 200 during the on-period of the second switch circuit, where the on-time may be one-time on-time or may be an accumulation of multiple on-times. For example, during the period of turning on the second switch circuit 300, the first switch circuit 201 is controlled to be turned on/off for a plurality of times, and the time lengths of the plurality of times of turning on are accumulated.

In this embodiment, the first switch circuit 201 and the second switch circuit 300 may include MOS transistors, triodes, or other switch transistors.

In this embodiment, the LED lamp set and the first switch circuit 201 are connected in series, specifically, the LED lamp set is connected in series between the first switch circuit 201 and the power input terminal VCC, or connected in series between the first switch circuit 201 and the ground terminal.

In this embodiment, one of the first switch circuit 201 and the second switch circuit 300 may be used to control the operating frequency of the LED lamp set, and the other may be used to control the average operating current of the LED lamp set.

In an embodiment, the main control chip 100 is configured to output N paths of first PWM signals, and correspondingly control a switching frequency of the first switch circuit 201 in the N paths of LED lamp branches 200 to control a working frequency of each path of LED lamp set, and at the same time, the main control chip 100 outputs a second PWM signal to control a conducting duration of the second switch circuit 300 during a period in which each path of the first switch circuit 201 is turned on to control an average working current of each path of LED lamp set, where the longer the conducting duration of the second switch circuit 300 is, the larger the average working current of the LED lamp set is; therefore, the working frequency and the average working current of the LED lamp group are separately controlled, and the condition that the duty ratio and the frequency of a plurality of paths of first PWM signals need to be configured simultaneously when the average working circuit or the working frequency of the LED lamp group is adjusted is avoided. In the present embodiment, the second switch circuit 300 is turned on during the turn-on of the first switch circuit 201.

For example, as shown in fig. 4, the N paths of the first PWM signals output by the main control chip 100 are respectively: the first PWM signal 1, the first PWM signal 2 to the first PWM signal N, which are not exhaustive in the figure; the N paths of first PWM signals can be PWM signals with high levels and the same duty ratio in turn; controlling the duty ratio of the second PWM signal in the high level duration of each path of the first PWM signal, namely controlling the average working current of the LED lamp set; the larger the duty ratio of the second PWM signal is, the larger the average working current of the corresponding LED lamp group is; when the duty ratio of the second PWM signal is 100%, the working current of the LED lamp set is the maximum; meanwhile, each time the first switch circuit 201 is turned on, the corresponding LED lamp set can be turned on, so that the frequency of the first PWM signal is controlled, that is, the switching frequency of the first switch circuit 201 is controlled, that is, the working frequency of the corresponding LED lamp set can be controlled.

In another embodiment, N paths of the first switch circuits 201 are turned on during the turning-on period of the second switch circuit 300, the main control chip 100 outputs a third PWM signal to control the switching frequency of the second switch circuit 300 so as to control the operating frequency of the LED lamp set, and at the same time, outputs N paths of fourth PWM signals to control the turn-on duration of the N paths of the first switch circuits 201 during the turning-on period of the second switch circuit 300 so as to control the average operating current of each path of the LED lamp set, wherein the longer the turn-on duration of the first switch circuit 201, the larger the average operating current of the corresponding LED lamp set; therefore, the working frequency and the average working current of the LED lamp are separately controlled, and the condition that the duty ratio and the frequency of a plurality of paths of first PWM signals need to be configured simultaneously when the average working circuit or the working frequency of the LED lamp group is adjusted is avoided.

In the present embodiment, the first switch circuit 201 is turned on during the turn-on period of the second switch circuit 300. During the period of one-time conduction and startup of the second switch circuit 300, when the N first switch circuits 201 are turned on in turn according to the time sequence, the LED lamp groups of the N LED lamp branches 200 are turned on in turn according to the time sequence.

For example, as shown in fig. 5, the N paths of the fourth PWM signals output by the main control chip 100 are respectively: a fourth PWM signal 1, a fourth PWM signal 2 to a fourth PWM signal N, which are not exhaustive in the drawing, and the N paths of the fourth PWM signals may be PWM signals with the same frequency and high levels appearing in turn; during the high level duration time of the third PWM signal, the N paths of fourth PWM signals alternately show high levels; at this time, the high level duration time of the N paths of fourth PWM signals is controlled, so that the average working current of the LED lamp set can be controlled, namely the brightness of the LED lamp set is controlled; meanwhile, each time the second switch circuit 300 is turned on, the LED lamp set is turned on; therefore, the frequency of the third PWM signal is controlled, and then the switching frequency of the second switching circuit 300 is controlled, i.e. the operating frequency of the LED lamp set is controlled.

It can be understood that the average working current of the LED lamp is controlled, i.e. the brightness of the LED lamp is controlled, and the working frequency of the LED lamp is controlled, i.e. the light emitting mode of the LED lamp is controlled, such as flashing, constant lighting or turning on of N-way LED lamps in turn. Because the first switch circuit 201 and the second switch circuit 300 are adopted to separately control the working frequency of the LED lamp and the average working current of the LED lamp, not only can a smooth LED display effect be obtained, but also the contradiction that the working frequency of the LED lamp and the average working current of the LED lamp interfere under certain control scenes can be solved.

In an embodiment, as shown in fig. 3, the LED lamp branch 200 includes a first resistor R1, a second resistor R2, a first switch tube Q1, and an LED lamp set; one end of the first resistor R1 is a controlled end of the first switch circuit 201; the other end of the first resistor R1 is interconnected with one end of the second resistor R2, the other end of the second resistor R2 is grounded, one end of the first resistor R1, which is interconnected with the second resistor R2, is connected with the gate of the first switch tube Q1, and the drain of the first switch tube Q1 is connected with the cathode of the LED lamp group; the LED lamp bank anode is connected with the power input end VCC, and the source electrode of the first switch tube Q1 is connected with the input end of the second switch circuit 300.

The first switch tube Q1 may be an NMOS tube, a PMOS tube or a triode; specifically according to the usage scenario.

In the present embodiment, the first switch Q1 is an NMOS transistor, and it is easy to understand that the PWM signal is a signal that alternately jumps between a high level and a low level; when the first PWM signal is in a high level state, the first switch Q1 is turned on, if the second switch circuit 300 is turned on during the period when the first switch circuit 201 is turned on, or the first switch circuit 201 is turned on during the period when the second switch circuit 300 is turned on, the power input VCC, the LED lamp set and the ground terminal form a loop, the LED lamp set is turned on, and when the first PWM signal is in a low level state, the first switch Q1 is turned off, and the LED lamp set is turned off.

It should be noted that, if the first switch tube Q1 is an NMOS tube, and the anode of the LED lamp is connected to the source of the first switch tube Q1, and the cathode of the LED lamp is connected to the output end or the ground end of the second switch circuit 300, at this time, due to the voltage division function of the LED lamp set, a larger turn-on voltage is needed to turn on the first switch tube Q1; at this time, the PMOS transistor may be used instead, and the amplitude of the first PWM signal input to the controlled terminal of the first switch circuit 201 may also be increased.

In another embodiment, the first switch transistor may be a PMOS transistor, and the first switch transistor Q1 may be turned on when the first PWM signal is in a low state, and the first switch transistor Q1 may be turned off when the first PWM signal is in a high state.

In an embodiment, as shown in fig. 3, the second switch circuit 300 includes a third resistor R3, a fourth resistor R4, and a second switch Q2; one end of the third resistor R3 is a controlled end of the second switch circuit 300, the other end of the third resistor R3 is interconnected with one end of the fourth resistor R4, the other end of the fourth resistor R4 is grounded, and the interconnected end of the third resistor R3 and the fourth resistor R4 is connected with the gate of the second switch tube Q2; the drain electrode of the second switching tube Q2 is connected with N paths of the LED lamp branches 200; the source of the second switch tube Q2 is grounded.

The second switch tube Q2 may be an NMOS tube, a PMOS tube, or a triode, which is specifically selected according to a usage scenario.

In this embodiment, the second switch Q2 is an NMOS transistor, and it is easy to understand that when the second PWM signal is in a high level state, the second switch Q2 is turned on, if the first switch circuit 201 is turned on during the period that the second switch circuit 300 is turned on, or the second switch circuit 300 is turned on during the period that the first switch circuit 201 is turned on, the power input VCC, the LED lamp set and the ground terminal form a loop, the LED lamp set is turned on, and when the second PWM signal is in a low level state, the second switch Q2 is turned off, and the LED lamp set is turned off.

In another embodiment, the second switch Q2 is also implemented by a PMOS transistor, and the second switch Q2 is turned on when the PWM signal is in a low state, and the second switch Q2 is turned off when the PWM signal is in a high state.

In one embodiment, as shown in fig. 3, the second switch circuit 300 further includes a fifth resistor R5 and a first capacitor C1; one end of the fifth resistor R5 is connected to the drain of the second switch transistor Q2, the other end is connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is connected to the source of the second switch transistor Q2.

It is easy to understand that the characteristic of the capacitor is that the ac current is direct, and the connection of the first capacitor C1 can prevent the voltage spike from being formed between the drain and the source of the switch tube at the moment of power-up, and the switch tube is broken down.

In an embodiment, the first switch transistor Q1 and the second switch transistor Q2 are MOS transistors.

It can be understood that the MOS tube is suitable for high-frequency and high-speed circuits and large-current occasions; of course, in low cost or other occasions, a triode or other switching device can be used as the switching tube.

In an embodiment, the LED lamp control circuit further includes a key circuit, the key circuit is connected to the main control chip, and the key circuit is configured to switch and output a plurality of key trigger signals to trigger the main control chip 100 to correspondingly control the switching frequency of the first switch circuit 201 or the second switch circuit, so as to adjust the operating frequency of the LED lamp set.

It can be understood that, the key circuit of this embodiment switches and outputs a plurality of key trigger signals, which may be a key trigger output multi-level trigger signal, for example, a first key is pressed down to trigger a first-level trigger signal, a second key is pressed down to trigger a second-level trigger signal, and the main control chip 100 outputs PWM signals with different frequencies according to different received trigger signals, so as to control the operating frequency of the LED lamp, thereby presenting different light emitting modes.

When the main control chip 100 receives different key trigger signals, the frequency of the first PWM signal may be adjusted, so as to adjust the operating frequency of the LED lamp set, and control the LED lamp set to exhibit different light emitting modes, such as flashing or constant lighting.

In one embodiment, as shown in figure 3,

the LED lamp control circuit further comprises:

the environment brightness acquisition device is used for acquiring environment brightness, converting the environment brightness into an electric signal and outputting the electric signal to the main control chip 100;

the main control chip 100 is further configured to correspondingly control the on-time of the first switch circuit 201 or the second switch circuit 300 according to the electrical signal when receiving the electrical signal, so as to adjust the average working current of the LED lamp set.

It can be understood that the brightness acquisition device outputs different electrical signals to the main control chip 100 according to the brightness of the environment, and when the main control chip 100 receives the electrical signals, the duty ratio of the second PWM signal can be adjusted, so as to adjust the average working current of the LED lamp set, that is, adjust the brightness of the LED lamp set, so that the brightness of the LED lamp set matches the environment.

In an embodiment, as shown in fig. 3, the ambient brightness acquiring apparatus includes a light dependent resistor LDR, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a third switching tube Q3; one end of the sixth resistor R6 is connected with the input end of the main control chip 100, the other end of the sixth resistor R6 is connected with one end of the light-sensitive resistor LDR, the other end of the light-sensitive resistor LDR is connected with the power input end VCC, one end of the sixth resistor R6 is connected with the seventh resistor R7, the other end of the seventh resistor R7 is connected with the drain of the third switch tube Q3, one end of the eighth resistor R8 is connected with one end of the ninth resistor R9, the other end of the eighth resistor R8 is connected with the output end of the main control chip 100, the other end of the ninth resistor R9 is grounded, one end of the eighth resistor R8 and the ninth resistor R9 is connected with the gate of the third switch tube Q3, and the source of the third switch tube Q3 is grounded.

It can be understood that, in this embodiment, the third switching tube Q3 is an NMOS tube, and when the end of the eighth resistor R8 connected to the output end of the main control chip 100 receives a low-level signal, the third switching tube Q3 is turned off, and at this time, no matter how the resistance value of the photosensitive resistor LDR changes, the input end of the main control chip 100 receives a constant voltage value, which is equivalent to turning off the ambient brightness collection function;

when the end of the eighth resistor R8 connected to the output end of the main control chip 100 receives a high level signal, the third switching tube Q3 is turned on, and at this time, the resistance ratio between the light sensitive resistor LDR and the seventh resistor R7 can determine the voltage value received by the input end of the main control chip 100, and as the brightness changes, the resistance of the light sensitive resistor LDR also changes, and at this time, the ambient brightness can be determined by setting a comparison table of the voltage value and the brightness.

In one embodiment, the LED lamp group comprises one LED lamp or a plurality of LEDs connected in parallel, so that a switching circuit can be reduced, and the cost can be reduced.

The invention also provides a baton, which is characterized in that the LED lamp control circuit is arranged on the baton; the specific structure of the LED lamp control circuit refers to the above embodiments, and since the baton adopts all the technical solutions of all the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and no further description is given here.

Wherein the baton may be a police baton or other baton.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. An LED lamp control circuit, comprising:

a power input terminal and a ground terminal;

2. The LED lamp control circuit according to claim 1, wherein the LED lamp branch comprises a first resistor, a second resistor, a first switch tube and an LED lamp group; one end of the first resistor is a controlled end of the first switch circuit; the other end of the first resistor is connected with one end of the second resistor, the other end of the second resistor is grounded, one end of the first resistor, which is connected with the second resistor, is connected with the grid electrode of the first switch tube, and the drain electrode of the first switch tube is connected with the cathode of the LED lamp bank; the anode of the LED lamp bank is connected with the power input end, and the source electrode of the first switch tube is connected with the input end of the second switch circuit.

3. The LED lamp control circuit according to claim 2, wherein the second switching circuit includes a third resistor, a fourth resistor, and a second switching tube; one end of the third resistor is a controlled end of the second switch circuit, the other end of the third resistor is interconnected with one end of the fourth resistor, the other end of the fourth resistor is grounded, and one end of the third resistor, which is interconnected with the fourth resistor, is connected with the grid electrode of the second switch tube; the drain electrode of the second switching tube is connected with the N paths of LED lamp branches; the source electrode of the second switch tube is grounded.

4. The LED lamp control circuit of claim 3, wherein the second switching circuit further comprises a fifth resistor and a first capacitor; one end of the fifth resistor is connected with the drain electrode of the second switch tube, the other end of the fifth resistor is connected with one end of the first capacitor, and the other end of the first capacitor is connected with the source electrode of the second switch tube.

5. The LED lamp control circuit according to claim 4, wherein the first switch tube and the second switch tube are both MOS tubes.

6. The LED lamp control circuit according to claim 1, further comprising a key circuit, wherein the key circuit is connected to the main control chip, and the key circuit is configured to switch and output a plurality of key trigger signals to trigger the main control chip to correspondingly control the switching frequency of the first switch circuit or the second switch circuit, so as to adjust the operating frequency of the LED lamp set.

7. The LED lamp control circuit of claim 1, wherein the LED lamp control circuit further comprises:

8. The LED lamp control circuit according to claim 7, wherein the ambient brightness collecting means comprises a photoresistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor and a third switching tube; the one end and the main control chip input of sixth resistance are connected, the other end and the one end interconnection of photo resistance of sixth resistance, photo resistance's the other end and power input end are connected, the one end and the seventh resistance of sixth resistance and photo resistance interconnection are connected, the other end and the third switch tube drain electrode of seventh resistance are connected, the one end of eighth resistance and the one end interconnection of ninth resistance, the other end and the main control chip output of eighth resistance are connected, the other end ground connection of ninth resistance, the one end and the third switch tube grid connection of eighth resistance and ninth resistance interconnection, third switch tube source ground connection.

9. The LED lamp control circuit of claim 1, wherein the LED lamp set comprises one LED lamp or a plurality of LEDs connected in parallel.

10. A baton comprising the LED lamp control circuit according to any one of claims 1 to 9.