CN210609800U

CN210609800U - Self-flashing LED lamp and control circuit thereof

Info

Publication number: CN210609800U
Application number: CN201921328169.4U
Authority: CN
Inventors: 王安; 莫容纪; 陈小勇
Original assignee: Taizhou Jiaojiang Yingxing Electronic Electrical Appliance Co ltd
Current assignee: Taizhou Jiaojiang Yingxing Electronic Electrical Appliance Co ltd
Priority date: 2019-08-15
Filing date: 2019-08-15
Publication date: 2020-05-22
Anticipated expiration: 2029-08-15

Abstract

The utility model provides a from scintillation LED lamp and control circuit for improve LED's application range, realize that LED often brightens and twinkle duplex mode. The self-flashing LED lamp comprises an LED lamp bead and an LED control circuit, wherein the output end of an H bridge direct current reversing circuit is connected with a driving chip, the control chip control end can output a forward signal for enabling the H bridge direct current reversing circuit to be conducted in the forward direction and a reverse signal for enabling the H bridge direct current reversing circuit to be conducted in the reverse direction, the forward signal controls the H bridge direct current reversing circuit to output working current when conducting in the forward direction, the control end alternately outputs the forward signal and the reverse signal, the reverse signal controls the H bridge direct current reversing circuit to output pulse current opposite to the working current when conducting in the reverse direction, and the current value of the pulse current is smaller than that of the working current. By the control mode, the LED which only can work in the flickering working mode can also work in the normally bright mode, and the application range of the self-flickering LED is improved.

Description

Self-flashing LED lamp and control circuit thereof

Technical Field

The utility model belongs to the technical field of lamps and lanterns, a from scintillation LED lamp and be used for controlling LED's control circuit is related to.

Background

The LED is a light emitting diode, and a plurality of LED lamp beads can be connected in series or in parallel to form an LED lamp string, which is widely used for festival decoration or light decoration of buildings at present.

The existing LED lamp string has two working modes of normally on and flickering. The driving modes of the LED lamp string in the blinking working mode are roughly two types: the flash circuit is a switch circuit which can be quickly switched on and off, and the flash mode is a synchronous flash mode of all the lamp strings; another asynchronous flashing mode, for example, the 'flashing control method and system of LED lamp string' disclosed in chinese patent application No. 201610957108.9, includes multiple groups of LED lamp strings and at least one driving chip, where the multiple groups of LED lamp strings are connected with the driving chip, and the flashing control method includes the following steps: pre-storing a plurality of display modes; setting a display sequence for the driving chip; and combining the display sequence to sequentially display each group of LED lamp strings according to the corresponding display mode. Therefore, by combining each group of LED lamp strings with a display sequence and flashing according to a display mode in sequence, asynchronous flashing effects such as running water flashing, mobile flashing or random flashing of the plurality of groups of LED lamp strings are realized.

The control is performed based on the LED lamp string in both the normally bright operating mode and the blinking operating mode, and although a plurality of display control modes are designed in the asynchronous blinking mode, the blinking control is performed based on the LED lamp string, which has certain limitations.

Therefore, it is proposed to perform control on the basis of a single LED, that is, a driving chip is integrated in one LED, and a main controller controls the single LED to flash in an addressing manner, so as to implement an asynchronous flash control manner to a greater extent. However, the driving chip of the single LED can only be designed to be in a control mode, namely, a normally on or flashing mode, and when the driving chip of the single LED is in the flashing mode (named as a self-flashing LED lamp bead), the self-flashing LED lamp bead cannot realize the normally on mode by using the existing mode, cannot meet the requirements of two working modes of normally on and flashing, and limits the use range.

Disclosure of Invention

The utility model discloses there is above-mentioned problem to current technique, has provided a from scintillation LED lamp and LED control circuit, and the technical problem of its solution is how to improve LED's application range, realizes that LED often brightens and twinkle duplex mode.

The utility model discloses a following technical scheme realizes:

a self-flashing LED lamp comprises an LED lamp bead and an LED control circuit, wherein the LED lamp bead comprises an LED and a driving chip capable of controlling the LED to work in a flashing mode, the LED control circuit comprises a control chip and an H-bridge direct-current reversing circuit, the output end of the H-bridge direct-current reversing circuit is connected with the driving chip, the control chip is provided with a control end connected with the H-bridge direct-current reversing circuit, the control end can output a forward signal for enabling the H-bridge direct-current reversing circuit to be conducted in a forward direction and a reverse signal for enabling the H-bridge direct-current reversing circuit to be conducted in a reverse direction, the forward signal controls the H-bridge direct-current reversing circuit to output working current when being conducted in the forward direction, the control end outputs a forward signal and a reverse signal alternately, and the reverse signal controls the H-bridge direct-current reversing circuit to output pulse current opposite to the working current when being conducted in the reverse direction, the current value of the pulse current is smaller than that of the working current.

The working process of the self-flashing LED lamp is as follows: the control chip outputs a forward signal to enable the H-bridge direct-current reversing circuit to be conducted in a forward direction, the output end of the H-bridge direct-current reversing circuit outputs forward direct current to enable the driving chip to be electrified, the driving chip enables the LED to work in a flickering mode, the H-bridge direct-current reversing circuit is kept conducted in the forward direction, and the LED is always in the flickering mode. When the LED is required to work in a normally-on mode, the control end outputs a forward signal and a reverse signal in a flashing time period of the LED, outputs the forward signal in a lighting time period of an LED flashing stage to enable the H-bridge direct-current reversing circuit to be conducted in a forward direction, the LED lights up, outputs the reverse signal in a blanking time period of the flashing stage to enable the H-bridge direct-current reversing circuit to be conducted in a reverse direction, outputs a reverse direct current to the drive chip from the output end of the H-bridge direct-current reversing circuit, the reverse direct current is a pulse current with a small current and is used for rapidly reducing the electric quantity of a holding capacitor and a parasitic capacitor in the drive chip to enable the drive chip to be powered off rapidly, namely, the blanking time period of the flashing stage is shortened, and then the process is repeated in the next flashing stage, because the reverse pulse current accelerates the power-off time of the drive chip, the LED is extinguished in a time period which, the LED can keep a normally-on state by repeating the steps. By the control mode, the LED which only can work in the flickering working mode can also work in the normally bright mode, and the application range of the self-flickering LED is improved.

In the self-flashing LED lamp, the driving chip has a power supply positive pin, a ground pin, and a control pin capable of outputting a high level and a low level for controlling the on and off of the LED, the LED is connected between the power supply positive pin and the control pin, and the power supply positive pin and the ground pin are connected to the output end of the H-bridge dc commutating circuit. The LED is controlled to be on or off through the high and low levels of the output pin of the driving chip, and the high and low levels of the output pin are controlled through programming or directly integrating a switching-on/off circuit in the driving chip.

In the self-flickering LED lamp, a reverse path of the H-bridge direct current commutation circuit is connected with a current-limiting resistor for limiting the magnitude of pulse current in the reverse path, a forward path of the H-bridge direct current commutation circuit is connected with a forward adjusting resistor, and the resistance value of the forward adjusting resistor is smaller than that of the current-limiting resistor. The pulse current can be controlled in a proper range through the current limiting resistor, and the negative influence of the pulse current on the driving chip is reduced.

In the self-flashing LED lamp, a plurality of LED lamp beads form a lamp string connected in parallel or in series.

In the self-flashing LED lamp, the reverse signal output time is less than 10 ms. The smaller the time, the better the effect of the normally bright mode.

An LED control circuit comprises a control chip and an H bridge direct current reversing circuit, wherein the control chip is provided with a control end connected with the H bridge direct current reversing circuit, the control end can output a forward signal for enabling the H bridge direct current reversing circuit to be conducted in a forward direction and a reverse signal for enabling the H bridge direct current reversing circuit to be conducted in a reverse direction, the forward signal controls the H bridge direct current reversing circuit to output working current when being conducted in the forward direction, the LED control circuit is characterized in that the control end alternately outputs the forward signal and the reverse signal, the reverse signal controls the H bridge direct current reversing circuit to output pulse current opposite to the working current when being conducted in the reverse direction, and the current value of the pulse current is smaller than that of the working current.

Aiming at the self-flashing LED lamp bead, the LED control circuit can realize two working modes of normal lighting and flashing.

In the LED control circuit, a current-limiting resistor for limiting the pulse current in the reverse path is connected between the reverse path of the H-bridge direct current commutation circuit and the control chip, and the current-limiting resistor is 10-1000K omega.

In the LED control circuit, a forward adjusting resistor is connected between a forward path of the H-bridge direct current commutation circuit and the control chip, and the resistance value of the forward adjusting resistor is smaller than that of the current limiting resistor.

In the LED control circuit, the reverse signal output time is less than 10 ms.

Compared with the prior art, the self-flickering LED lamp has the following advantages:

1. the utility model discloses a reverse pulse current has accelerated driver chip's outage time, and the time that LED extinguishes is little to the naked eye to be difficult to perceive LED at the scintillation, through this kind of mode control mode, makes from flashing LED also can realize often under the bright mode, has improved this kind of application range from flashing LED.

2. The lamp string composed of the self-flickering LEDs is matched with the LED driving circuit of the scheme, two working modes of flickering and normally-on are realized, the service life is longer, and the application cost of the self-flickering LED lamp string is reduced compared with the lamp string composed of the normally-on LEDs and a control circuit.

Drawings

Fig. 1 is a schematic structural diagram of a self-flashing LED lamp bead in the first embodiment.

FIG. 2 is a schematic diagram of a control circuit of a self-flashing LED according to a first embodiment.

Fig. 3 is a state diagram of the output terminal of fig. 2 connected to the high and low levels of the LED.

Fig. 4 is a schematic diagram of a forward signal and a reverse signal sent by the control chip in fig. 2, so as to realize that the self-flashing LED lamp bead is normally on.

In the figure, 1, LED lamp beads; 2. a driving chip; 21. a power supply positive pin; 22. a grounding lead; 23. a control pin; 3. a control chip; l1, first control leg; l2, second control leg; 4. an H-bridge direct current commutation circuit; 41. a first output terminal; 42. a second output terminal; switching tubes Q1, Q2, Q3 and Q4; r1, forward regulation resistance; r2, current limiting resistor; r3, R4 switching resistors.

Detailed Description

The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

The first embodiment is as follows:

as shown in fig. 1, the self-flashing LED lamp bead 1 includes an LED and a driving chip 2, the driving chip 2 is provided with a power supply positive pin 21, a ground pin 22 and a control pin 23 capable of outputting high and low levels, an anode of the LED is connected with the power supply positive pin 21, a cathode of the LED is connected with the control pin 23, and the power supply positive pin 21 and the ground pin 22 extend out of a lamp housing of the LED lamp bead 1 and serve as a positive connecting pin and a negative connecting pin of the LED lamp bead 1. Be equipped with programmable memory in driver chip 2, driver chip 2's central processing unit lets driver chip 2's control pin 23 spaced output high-low level according to the circulation procedure in the memory, when control pin 23 output low level, the LED passageway is luminous, when control pin 23 output high level, LED ends and extinguishes, so reciprocal, can make the scintillation that LED does not stop after driver chip 2 obtains, LED lamp pearl 1 of this kind of structure also is from twinkling of an eye LED lamp pearl 1.

As shown in fig. 2 and 3, fig. 2 is a control circuit of an LED, which includes a control chip 3 and an H-bridge dc commutating circuit 4. The control terminal 31 of the control chip 3 includes a first control pin L1 and a second control pin L2 capable of generating a high level and a low level, and when the first control pin L1 is in a low level state and the second control pin L2 is in a high level state, the control chip 3 outputs a forward signal to the H-bridge dc commutating circuit 4 through the first control pin L1 and the second control pin L2; when the first control pin L1 is in a high state and the second control pin L2 is in a low state, the control chip 3 outputs an inverted signal to the H-bridge dc commutating circuit 4 through the first control pin L1 and the second control pin L2. The high and low levels of the first control pin L1 and the second control pin L2 are set by a program in the control chip 3.

The H-bridge direct current commutation circuit 4 comprises four switching tubes Q1, Q2, Q3, Q4 and a direct current commutation circuit formed by two output ends, wherein the output ends of the H-bridge direct current commutation circuit 4 are a first output end 41 and a second output end 42, the switching tubes Q1 and Q4 form a forward path, a collector of the switching tube Q1 is connected with the first output end 41, a collector of the switching tube Q4 is connected with the second output end 42, a collector of the switching tube Q1 is connected with a base of the switching tube Q2 through a conversion resistor R3, an emitter of the switching tube Q1 is connected with a positive electrode of a power supply, and an emitter of the switching tube Q4 is grounded. The switching tubes Q2 and Q3 form a reverse path, the collector of the switching tube Q2 is connected with the base of the switching tube Q2 through a conversion resistor R4, the emitter of the switching tube Q2 is connected with the positive electrode of a power supply, the emitter of the switching tube Q3 is grounded, the collector of the switching tube Q2 is connected with the second output end 42, the collector of the switching tube Q3 is connected with the first output end 41, the first control pin 23 of the control chip 3 is connected with the base of the switching tube Q1 through a forward adjusting resistor R1, and the second control pin 23 of the control chip is connected with the base of the switching tube Q2 through a current limiting resistor R2. The current limiting resistor R2 is 10K omega-1000K omega and is used for limiting the current of the reverse path, the reverse current is small current when the reverse path is conducted, the resistance value of the forward adjusting resistor R1 is smaller than the resistance value of the current limiting resistor R2, the phase difference is generally 150-250 times, and the forward current is working current capable of driving the LED lamp bead 1 to emit light when the forward path is conducted.

When the control end of the control chip 3 outputs a forward signal, the H-bridge direct current commutation circuit 4 can be conducted in a forward direction, and when the control end of the control chip 3 outputs a reverse signal, the H-bridge direct current commutation circuit 4 can be conducted in a reverse direction. Specifically, when the control chip 3 is in a state of outputting a forward signal, the first control pin L1 is in a low level state, the switching tubes Q1 and Q4 are turned on, the first output terminal 41 outputs a high level, the second control pin L2 is in a high level state, the switching tubes Q2 and Q3 are turned off, and the second output terminal 42 outputs a low level; the power positive pin 21 of the driving chip 2 connected to the first output terminal 41 is powered on, the driving chip 2 starts to work, if the control chip 3 outputs a positive signal all the time, the driving chip 2 works all the time, and the LED works in a flashing working mode all the time. When the control chip 3 is in a state of outputting a reverse signal, the first control pin L1 is in a high level state, the switching tubes Q1 and Q4 are cut off, the first output end 41 outputs a low level, the second control pin L2 is in a low level state, the switching tubes Q2 and Q3 are turned on, and the second output end 42 outputs a high level, so that the negative pin of the power supply of the driving chip 2 is connected with the first output end 41 in the high level state, and the positive pin 21 of the power supply of the driving chip 2 is connected with the second output end 42 in the low level state, so that the electric quantity of the holding capacitor inside the driving chip 2 and the electric quantity of the parasitic capacitor are quickly consumed, and the driving chip 2 is quickly powered off. Due to the current limiting resistor R2, the reverse current is small, and does not affect the inside of the driver chip 2.

As shown in fig. 4, when the control terminal alternately outputs a forward signal and a reverse signal, and the reverse signal controls the H-bridge dc commutating circuit 4 to be turned on in the reverse direction, a reverse current opposite to the working current is output, and the reverse current is only used for quickly depleting the electric quantity of the capacitor C, so that the reverse current has a short duration, and a reverse pulse current is formed. Specifically, a forward signal and a reverse signal are output during a flashing time period t of the LED, during the lighting time period t1 of an LED flashing stage t, a forward signal is output to make the H-bridge DC commutation circuit 4 conduct in the forward direction, the LED lights up, then, outputting a reverse signal to reversely conduct the H-bridge DC commutating circuit 4 at the extinguishing time t2 of the flashing stage, outputting a reverse pulse current at the output end of the H-bridge DC commutating circuit 4 to rapidly power off the driving chip 2, shortening the extinguishing time t2 of one flashing stage, and then repeating the above processes in the next flashing stage t, because the reverse pulse current accelerates the power-off time of the driving chip 2, the LED is extinguished for a time as short as the naked eye can hardly perceive that the LED flickers, and the extinguishing time t2 of the LED is generally set to be less than 10 milliseconds, so that the LED can be kept in a normally-on state by repeating the cycle.

In this example, the LED lamp beads 1 may be controlled individually, or a plurality of LED lamp beads 1 may form a lamp string connected in parallel or in series.

The specific embodiments described herein are merely illustrative of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Claims

1. A self-flashing LED lamp comprises an LED lamp bead (1) and an LED control circuit, wherein the LED lamp bead (1) comprises an LED and a driving chip (2) capable of controlling the LED to work in a flashing mode, the LED control circuit comprises a control chip (3) and an H bridge direct current reversing circuit (4), the output end of the H bridge direct current reversing circuit (4) is connected with the driving chip (2), the control chip (3) is provided with a control end (31) connected with the H bridge direct current reversing circuit (4), the control end (31) can output a forward signal for enabling the H bridge direct current reversing circuit (4) to be conducted in a forward direction and a reverse signal for enabling the H bridge direct current reversing circuit (4) to be conducted in a reverse direction, the forward signal controls the H bridge direct current reversing circuit (4) to output a working current when being conducted in the forward direction, and is characterized in that the control end (31) alternately outputs the forward signal and the reverse signal, and the reverse signal controls the H bridge direct current commutation circuit (4) to output pulse current opposite to the working current when conducting reversely, and the current value of the pulse current is smaller than that of the working current.

2. The self-flashing LED lamp according to claim 1, wherein the driving chip (2) has a positive power pin (21), a ground pin (22) and a control pin (23) capable of outputting high and low levels for controlling the LED to turn on and off, the LED is connected between the positive power pin (21) and the control pin (23), and the positive power pin (21) and the ground pin (22) are connected with the output end of the H-bridge DC commutating circuit (4).

3. The self-flickering LED lamp according to claim 1 or 2, wherein a current limiting resistor (R2) for limiting the magnitude of pulse current in a reverse path is connected between the reverse path of the H-bridge DC commutation circuit (4) and the control chip (3), a forward adjusting resistor (R1) is connected between a forward path of the H-bridge DC commutation circuit (4) and the control chip (3), the resistance of the forward adjusting resistor (R1) is smaller than that of the current limiting resistor (R2), and the current limiting resistor (R2) is 10K Ω -1000K Ω.

4. The self-flashing LED lamp of claim 3, wherein the reverse signal output time is less than 10 ms.

5. The self-flashing LED lamp as claimed in claim 4, wherein the number of the LED lamp beads (1) is multiple, and the LED lamp beads are connected in parallel or in series to form a lamp string.

6. An LED control circuit comprises a control chip (3) and an H bridge direct current reversing circuit (4), wherein the control chip (3) is provided with a control end (31) connected with the H bridge direct current reversing circuit (4), the control end (31) can output a forward signal for enabling the H bridge direct current reversing circuit (4) to be conducted in a forward direction and a reverse signal for enabling the H bridge direct current reversing circuit (4) to be conducted in a reverse direction, the forward signal controls the H bridge direct current reversing circuit (4) to output a working current when conducting in the forward direction, and the LED control circuit is characterized in that the control end (31) alternately outputs the forward signal and the reverse signal, the reverse signal controls the H bridge direct current reversing circuit (4) to output a pulse current opposite to the working current when conducting in the reverse direction, and the current value of the pulse current is smaller than that of the working current.

7. The LED control circuit according to claim 6, wherein a current limiting resistor (R2) for limiting the magnitude of the pulse current in the reverse path is connected between the reverse path of the H-bridge DC commutating circuit (4) and the control chip (3), and the current limiting resistor (R2) is 10K Ω -1000K Ω.

8. The LED control circuit according to claim 7, wherein a forward adjusting resistor (R1) is connected between the forward path of the H-bridge DC commutating circuit (4) and the control chip (3), and the resistance of the forward adjusting resistor (R1) is smaller than that of the current limiting resistor (R2).

9. The LED control circuit of claim 7, wherein the reverse signal output time is less than 10 ms.