Lamp strip control circuit

Abstract

The utility model relates to a lamp strip control circuit, comprising an input interface, a rectification filter circuit, a power switch device, a transformer, an output rectification filter circuit, an output interface, a PWM control circuit, a feedback circuit and an MCU, the feedback circuit and the PWM control circuit are connected between the output rectification filter circuit and the power switch device to form a control loop; and an MCU is arranged between the feedback circuit and the input interface. The utility model has the functions and advantages of brightness control and no stroboflash, and can be used under more conditions by matching with the characteristic that the length of the lamp strip can be cut and adjusted according to the actual demand, and the MCU mainly realizes the gear memory function, so that the LED lamp strip can be conveniently used. On the basis of the arrangement, the constant voltage can be realized by matching with the transformer disclosed by the utility model, so that the lamp strip driven to work by the circuit disclosed by the utility model can achieve the advantages of multi-gear memory brightness circulation adjustment and no stroboflash.

Description

Technical Field

[0001] The utility model belongs to the technical field of lighting, and in particular relates to a light belt control circuit. Background Art

[0002] With the continuous development of LED (Light Emitting Diode) technology, the development of LED decoration has been driven, and a series of new technologies and new products have been developed, and light strip products have also emerged. LED light strips are not only widely used in lighting projects that outline iconic buildings, towers, bridges, parks and squares, but have also become an important part of industrial design to attract customers.

[0003] The current control method of LED light strips requires a special light strip driver chip, and the IO (Input / Output) timing of the special light strip driver chip is controlled by software to simulate the light strip IC (Integrated Circuit Chip) timing, thereby controlling the light state of the light strip.

[0004] However, the brightness, color and mode of the light strips in the prior art are relatively simple, the user experience is poor, and sometimes flickering occurs, causing discomfort to the user's eyes. Utility Model Content

[0005] In order to solve the above problems, the utility model adopts the following technical solutions:

[0006] A light strip control circuit comprises an input interface, a rectifier and filter circuit, a power switch device, a transformer, an output rectifier and filter circuit, an output interface, a power PWM control chip, a feedback circuit and an MCU, wherein the input end of the input interface is electrically connected to the mains phase through a wall switch so as to perform power-on or power-off operations based on the wall switch; an EMC, a rectifier and filter circuit, a power switch device, a transformer and an output rectifier and filter circuit are sequentially connected in series between the output end of the input interface and the input end of the output interface; the output end of the output interface is plugged into the light strip to be controlled; a feedback circuit and a power PWM control chip are connected between the output rectifier and filter circuit and the power switch device to form a control loop; an MCU is arranged between the feedback circuit and the input interface.

[0007] Preferably, the power switch device is a MOS tube.

[0008] Preferably, the MCU has several duty cycle data preset, each duty cycle data corresponds to an output voltage, and the output of the duty cycle is that the MCU sends a working electrical signal to the feedback circuit and then reaches the optocoupler U3, and then the optocoupler U3 transmits the working electrical signal to the power supply PWM control chip to control the output corresponding voltage.

[0009] Preferably, the switching of several output voltage levels in the MCU is performed by turning off the electrical wall switch and then turning on the power again within 0.2 seconds to 1 second, and the switching order is sequential and cyclical according to the setting.

[0010] Preferably, one pin of the MCU is a power pin, two pins are output pins, seven pins are signal collection pins, and eight pins are ground pins.

[0011] Preferably, the seven pins of the MCU collect the mains power through a diode D1, a resistor R1 and a resistor R2 via an optocoupler U2.

[0012] Preferably, the MCU includes a first PWM control circuit, and the power supply PWM control chip includes a second PWM control circuit.

[0013] Preferably, the second pin of the MCU will output an electrical signal of the first PWM control circuit, and the electrical signal will reach and pass through the switch tube Q2 to change the parallel resistance value of the four resistors, namely, resistor R19, resistor R20, resistor R17 and resistor R18, to control the conduction current of the controllable voltage regulator U5, and the electrical signal of the controllable voltage regulator U5 will subsequently be transmitted to the power supply PWM control chip via the optical coupler U3 to control the output voltage of the power supply PWM control chip.

[0014] Preferably, the output voltage gear can be selected in the range of 7V to 12V, or 15V to 24V, that is, a plurality of gears can be divided between 7V to 12V or 15V to 24V.

[0015] Compared with the prior art, the advantages of the present invention are: the present invention is a light strip control circuit, which has the functions and advantages of brightness control and no flicker, and the length of the light strip can be cut and adjusted according to actual needs, which allows the present invention to meet the use in more situations, wherein the brightness control is based on the two pins of the MCU changing the parallel resistance of the four resistors R19, R20, R17 and R18 through the switch tube Q2 to control the output voltage, wherein the MCU can preset several gears of duty cycle data to correspond to several gears of output voltage, and the output of the duty cycle is controlled by the set power supply PWM control chip, and the MCU mainly realizes the gear memory function. Based on the above settings, the transformer described in the present invention is used to achieve constant voltage, so that the light strip driven by the present invention can achieve several gears of memory brightness cycle adjustment and no flicker. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a principle block diagram of the utility model.

[0017] Figure 2 This is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] View First Figure 2 , U4 in the figure is the MCU (13) described in the present invention, which includes a first PWM control circuit, and U1 in the figure is the power supply PWM control chip (11) described in the present invention, which includes a second PWM control circuit.

[0020] like Figure 1 and Figure 2As shown, the utility model mainly comprises an input interface (3), an EMC (4), a rectifier filter circuit (5), a power switch device (6), a transformer (7), an output rectifier filter circuit (8), an output interface (9), a PWM control circuit (11), a feedback circuit (12) and an MCU (13), wherein the input end of the input interface (3) is electrically connected to the mains (1) via a wall switch (2), and the wall switch (2) is a switch for controlling the power off or on of the utility model, and is also a key for switching the brightness level. The input city power (2) is connected or disconnected; an EMC (4), a rectifier filter circuit (5), a power switch device (6), a transformer (7) and an output rectifier filter circuit (8) are sequentially connected in series between the output end of the input interface (3) and the input end of the output interface (9); the output end of the output interface (9) is plugged into a light strip (10) to be controlled; a feedback circuit (12) and a PWM control circuit (11) are connected between the output rectifier filter circuit (8) and the power switch device (6) to form a control circuit. A control loop is provided, wherein an MCU (13) is provided between the feedback circuit (12) and the input interface (3), wherein if the MCU (13) is preset with five duty cycles corresponding to five output voltages, the five output voltages can be set to 15.4V, 18V, 20V, 22V and 23.7V respectively, or five output voltages can be set as required within the range of 7V to 12V, thereby satisfying the use of the utility model by lamps with different input voltage specifications, and the duty cycle data stored in the MCU (13) is obtained after being fed back through the feedback circuit (12). After the electrical signal is sent, the control adjustment is realized through the power PWM control chip (11), and finally the brightness is realized in the set five gears. The parallel resistance value of the four resistors R19, R20, R17 and R18 is changed through the switch tube Q2 based on the two pins of the MCU (13) to control the conduction current of the controllable voltage regulator U5, and the electrical signal of the controllable voltage regulator U5 will be transmitted to the power PWM control chip (11) through the optical coupler U3 to control the output voltage of the power PWM control chip (11). The MCU (13) and the power PWM control chip (11) cooperate with each other to realize the research and development purposes of gear memory, gear constant voltage output and brightness switching, and the voltage output by the parallel resistance value of the four resistors R19, R20, R17 and R18 is switched in the range of 7V to 12V or 15.4-23.7V.

[0021] The utility model is specifically based on U4, that is, the MCU (13) to work, wherein one pin of the MCU (13) is a power pin, two pins are output pins, seven pins are signal collection pins, and eight pins are ground pins, wherein the seven pins collect the mains power (1) through a diode D1, a resistor R1 and a resistor R2 via an optical coupler U2, and each time the power is cut off, a different duty cycle is output from the two pins, specifically, the first PWM control circuit in the MCU (13) changes the parallel value of the four resistors, namely, the resistor R19, the resistor R20, the resistor R17 and the resistor R18. The output voltage is controlled by connecting a resistance value, thereby achieving the purpose of changing the output voltage. In more detail, the two pins of the MCU (13) can output a plurality of output voltages according to the preset duty cycle data. The cyclic switching of the output voltage controls the switching of the brightness levels of the connected light strip. Based on this design, the research and development purpose of the present invention can be achieved, that is, the brightness can be cyclically adjusted, and based on the MCU (13), it can also have a memory function, and cooperate with the transformer to achieve constant voltage, so that the light strip used in conjunction with the present invention has the advantages of a plurality of current memory brightness and no flicker.

[0022] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In the present utility model, unless otherwise clearly specified and limited, the first feature "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description of reference terms "one scheme", "some schemes", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the scheme or example are included in at least one scheme or example of the present utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same scheme or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more schemes or examples.

Claims

1. A light strip control circuit, comprising an input interface (3), a rectifying and filtering circuit (5), a power switch device (6), a transformer (7), an output rectifying and filtering circuit (8), an output interface (9), a power PWM control chip (11), a feedback circuit (12) and an MCU (13), wherein the input end of the input interface (3) is electrically connected to a mains power supply (1) through a wall switch (2) so as to perform a power-on or power-off operation based on the wall switch (2); an EMC (4), a rectifying and filtering circuit (5), a power switch device (6), a transformer (7) and an output rectifying and filtering circuit (8) are sequentially connected in series between the output end of the input interface (3) and the input end of the output interface (9); the output end of the output interface (9) is plugged into a light strip (10) to be controlled; a feedback circuit (12) and a power PWM control chip (11) are connected between the output rectifying and filtering circuit (8) and the power switch device (6) to form a control loop; and an MCU (13) is arranged between the feedback circuit (12) and the input interface (3).

2. A light strip control circuit according to claim 1, characterized in that: The power switch device (6) is a MOS tube.

3. The light strip control circuit according to claim 1, characterized in that: The MCU (13) is preset with a plurality of duty cycle data, each duty cycle data corresponding to a level of output voltage. The duty cycle output is that the MCU (13) sends a working electrical signal to the feedback circuit (12) and then reaches the optical coupler U3, and then transmits the working electrical signal to the power PWM control chip (11) via the optical coupler U3 to control the output of the corresponding voltage.

4. A light strip control circuit according to claim 3, characterized in that: The switching of the output voltages of the MCU (13) is performed by disconnecting the wall switch (2) and then switching it on again within 0.2 seconds to 1 second, and the switching sequence is set in sequence and in a cycle.

5. The light strip control circuit according to claim 1, characterized in that: One pin of the MCU (13) is a power pin, two pins are output pins, seven pins are signal collection pins, and eight pins are ground pins.

6. A light strip control circuit according to claim 5, characterized in that: The seven pins of the MCU (13) collect the mains power (1) through a diode D1, a resistor R1 and a resistor R2 via an optical coupler U2.

7. The light strip control circuit according to claim 1, characterized in that: The MCU (13) includes a first PWM control circuit, and the power supply PWM control chip (11) includes a second PWM control circuit.

8. The light strip control circuit according to claim 6, characterized in that: The two pins of the MCU (13) will output an electrical signal of the first PWM control circuit, and the electrical signal will reach and pass through the switch tube Q2 to change the parallel resistance value of the four resistors, namely, the resistor R19, the resistor R20, the resistor R17 and the resistor R18, so as to control the conduction current of the controllable voltage regulator U5, and the electrical signal of the controllable voltage regulator U5 will subsequently be transmitted to the power supply PWM control chip (11) via the optical coupler U3 to control the output voltage of the power supply PWM control chip (11).

9. The light strip control circuit according to claim 8, characterized in that: The output voltage gear can be selected in the range of 7V to 12V, or 15V to 24V, that is, a plurality of gears can be divided between 7V to 12V or 15V to 24V.

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