Adjustable voltage circuit based on single-chip microcomputer control

Abstract

The utility model relates to an adjustable voltage circuit based on single-chip microcomputer control, which is used for adjusting LED light brightness and comprises an input filter circuit, a control circuit and a voltage output circuit which are sequentially connected, the input end of the input filter circuit is connected to the PWM signal output end of the single-chip microcomputer, the output end of the input filter circuit is connected to the input end of the control circuit, and the output end of the control circuit is connected to the output end of the voltage output circuit. The voltage output circuit comprises a controllable precision voltage stabilization source U2 and a voltage sampling circuit. The voltage output circuit outputs stable voltage under the control of the control circuit. A PWM signal output by the single-chip microcomputer is filtered by the input filter circuit, then transmitted to the control circuit and then transmitted to the voltage output circuit through the optocoupler OT2, and the voltage output circuit outputs a voltage signal modulated by the PWM signal, provides voltage signals with different pulse widths and amplitudes for an LED lamp, and is used for adjusting the light brightness and color temperature of the LED lamp so as to adapt to various different application scenes. The circuit device is simple in structure, low in cost and high in universality, and can be used for various LED application scenes.

Description

TECHNICAL FIELD

[0001] The utility model relates to LED control technical field, concretely relates to a adjustable voltage circuit based on singlechip control. BACKGROUND

[0002] With the continuous development of light emitting diode (Light Emitting Diode, LED) lighting technology, the market demand for LED lighting devices is increasingly strong, as one of the representative functions of LED lighting dynamic control, the optimization and upgrading of dimming function has become the core element of intelligent and healthy lighting technology research.

[0003] LED is widely used in the market, and the brightness requirements are different in different scenes. PWM dimming is one of the commonly used brightness adjustment technologies. PWM dimming is a technology for controlling the brightness of a light source by adjusting the pulse width. It operates in a bright-dark alternating manner within a specific time period by rapidly switching the backlight or light source, and adjusts the brightness by adjusting the bright-dark time ratio. The main parameters of PWM dimming include dimming frequency and duty cycle. The duty cycle refers to the proportion of the high level in the entire cycle of the pulse signal, and the frequency refers to the cycle of the PWM signal. However, the circuit structure used in the existing PWM dimming technology is complex and has poor versatility. SUMMARY

[0004] Therefore, it is necessary to provide a adjustable voltage circuit based on singlechip control with simple circuit structure and applicable to different scenes.

[0005] A adjustable voltage circuit based on singlechip control for adjusting the brightness of LED light, comprising input filter circuit, control circuit and voltage output circuit connected in sequence, the input end of the input filter circuit is connected to the PWM signal output end of the singlechip, the output end of the input filter circuit is connected to the input end of the control circuit, the voltage output circuit comprises controllable precision voltage source U2 and voltage sampling circuit, and the voltage output circuit outputs stable voltage under the control of the control circuit.

[0006] Preferably, the input filter circuit comprises a first resistor R15, a first capacitor C6 and a second resistor R12; one end of the first resistor R15 is connected to the signal output end PWM2 of the singlechip, the other end of the first resistor R15 is connected to the output end of the input filter circuit through the second resistor R12; one end of the first capacitor C6 is connected to the connection point between the first resistor R15 and the second resistor R12, and the other end of the first capacitor C6 is grounded.

[0007] Preferably, the control circuit comprises an optical coupling OT2 and a third resistor R28, one end of the third resistor R28 is connected to the input end of the control circuit, the other end of the third resistor R28 is connected to the anode of the light emitting diode OT2-B of the optical coupling OT2, and the cathode of the light emitting diode OT2-B of the optical coupling OT2 is grounded.

[0008] Preferably, the voltage sampling circuit comprises a fourth resistor R10, a fifth resistor R27 and a sixth resistor R13 connected in series, and the free end of the fourth resistor R10 is connected to the output end of the voltage output circuit, and the free end of the sixth resistor R13 is grounded.

[0009] Preferably, the collector and the emitter of the phototriode OT2-A of the optical coupling OT2 are connected in parallel to the two ends of the fifth resistor R27.

[0010] Preferably, the reference electrode of the controllable precision voltage source U2 is connected to the connection point between the collector of the phototriode OT2-A of the optical coupling OT2, the fourth resistor R10 and the fifth resistor R27, the cathode of the controllable precision voltage source U2 is connected to the output end of the voltage output circuit through a seventh resistor R9, and the anode of the controllable precision voltage source U2 is grounded.

[0011] In the adjustable voltage circuit based on single-chip microcomputer control, the PWM signal output by the single-chip microcomputer is filtered through the input filter circuit, transmitted to the control circuit, and then transmitted to the voltage output circuit by the optical coupling OT2, and the voltage output circuit outputs the voltage signal modulated by the PWM signal, so as to provide the voltage signal with different pulse widths and amplitudes for the LED lamp, and adjust the light brightness and color temperature of the LED, so as to adapt to various application scenarios. The circuit device has simple structure, low cost and high universality, and can be used in various LED application scenarios. The circuit structure of the utility model is simple, easy to realize, low in cost, and convenient to popularize. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a circuit structure schematic view of the adjustable voltage circuit based on single-chip microcomputer control of the utility model embodiment. DETAILED DESCRIPTION

[0013] The utility model will be described in detail below in combination with specific embodiments and drawings.

[0014] Please refer to Figure 1 , show the adjustable voltage circuit based on single-chip microcomputer control provided by the utility model embodiment,

[0015] The application discloses a device for adjusting the brightness of LED light, which comprises an input filter circuit, a control circuit and a voltage output circuit connected in sequence, wherein the input end of the input filter circuit is connected to the PWM signal output end of a single-chip microcomputer, the output end of the input filter circuit is connected to the input end of the control circuit, and the voltage output circuit comprises a controllable precision voltage source U2 and a voltage sampling circuit, and the voltage output circuit outputs a stable voltage under the control of the control circuit.

[0016] Preferably, the input filter circuit comprises a first resistor R15, a first capacitor C6 and a second resistor R12, one end of the first resistor R15 is connected to the signal output end PWM2 of the single-chip microcomputer, the other end of the first resistor R15 is connected to the output end of the input filter circuit through the second resistor R12, one end of the first capacitor C6 is connected to the connecting point between the first resistor R15 and the second resistor R12, and the other end of the first capacitor C6 is grounded.

[0017] Specifically, the first resistor R15, the second resistor R12 and the first capacitor C6 constitute an RC filter circuit to filter high-frequency components in the circuit.

[0018] Preferably, the control circuit comprises an optical coupler OT2 and a third resistor R28, one end of the third resistor R28 is connected to the input end of the control circuit, the other end of the third resistor R28 is connected to the anode of the light-emitting diode OT2-B of the optical coupler OT2, and the cathode of the light-emitting diode OT2-B of the optical coupler OT2 is grounded.

[0019] Preferably, the voltage sampling circuit comprises a fourth resistor R10, a fifth resistor R27 and a sixth resistor R13 connected in sequence, the free end of the fourth resistor R10 is connected to the output end of the voltage output circuit, and the free end of the sixth resistor R13 is grounded. The collector and the emitter of the phototriode OT2-A of the optical coupler OT2 are connected in parallel to the two ends of the fifth resistor R27. The reference electrode of the controllable precision voltage source U2 is connected to the connecting point between the collector of the phototriode OT2-A of the optical coupler OT2, the fourth resistor R10 and the fifth resistor R27, the cathode of the controllable precision voltage source U2 is connected to the output end of the voltage output circuit through a seventh resistor R9, and the anode of the controllable precision voltage source U2 is grounded.

[0020] Specifically, the PWM signal output by the single-chip microcomputer is transmitted to the control circuit after being filtered by the input filter circuit, and the light-emitting diode OT2-B of the optical coupler OT2 transmits the PWM signal to the phototriode OT2-A.

[0021] When the phototriode OT2-A is turned off, the output voltage Vout of the voltage output circuit is Vref*(1+R10 / (R27+R13)).

[0022] When the phototriode OT2-A is turned on, the output voltage Vout of the voltage output circuit is Vref*(1+R10 / R13).

[0023] Therefore, the output voltage of the voltage output circuit depends on the resistance values of the fourth resistance R10, the fifth resistance R27 and the sixth resistance R13, and the pulse width of the output voltage depends on the pulse width of the PWM signal output by the single-chip microcomputer, so as to adjust the light brightness and color temperature of the LED to adapt to various application scenarios.

[0024] In the adjustable voltage circuit based on the single-chip microcomputer control, the PWM signal output by the single-chip microcomputer is filtered by the input filter circuit, transmitted to the control circuit, and then transmitted to the voltage output circuit by the optocoupler OT2, and the voltage output circuit outputs the voltage signal modulated by the PWM signal to provide the LED lamp with voltage signals with different pulse widths and amplitudes, so as to adjust the light brightness and color temperature of the LED to adapt to various application scenarios. The circuit device has simple structure, low cost and high universality, and can be used in various LED application scenarios. The circuit structure of the utility model is simple, easy to realize, low in cost and convenient to popularize.

[0025] It should be noted that the utility model is not limited to the above-mentioned embodiments, and other changes can be made by those skilled in the art according to the creative spirit of the utility model, and the changes made according to the creative spirit of the utility model should be included in the scope of protection of the utility model.

Claims

1. A single-chip microcomputer control-based adjustable voltage circuit for adjusting the brightness of an LED light, characterized by, The input filter circuit, the control circuit and the voltage output circuit are connected in sequence, the input end of the input filter circuit is connected to the PWM signal output end of the single-chip microcomputer, the output end of the input filter circuit is connected to the input end of the control circuit, the voltage output circuit comprises a controllable precision voltage stabilizer U2 and a voltage sampling circuit, and the voltage output circuit outputs a stable voltage under the control of the control circuit.

2. The single-chip microcomputer control-based adjustable voltage circuit according to claim 1, wherein The input filter circuit comprises a first resistor R15, a first capacitor C6 and a second resistor R12, one end of the first resistor R15 is connected to the signal output end PWM2 of the single-chip microcomputer, the other end of the first resistor R15 is connected to the output end of the input filter circuit through the second resistor R12, one end of the first capacitor C6 is connected to the connecting point between the first resistor R15 and the second resistor R12, and the other end of the first capacitor C6 is grounded.

3. The single-chip microcomputer control-based adjustable voltage circuit according to claim 1, wherein The control circuit comprises an optical coupler OT2 and a third resistor R28, one end of the third resistor R28 is connected to the input end of the control circuit, the other end of the third resistor R28 is connected to the anode of the light-emitting diode OT2-B of the optical coupler OT2, and the cathode of the light-emitting diode OT2-B of the optical coupler OT2 is grounded.

4. The single-chip microcomputer control-based adjustable voltage circuit according to claim 3, wherein The voltage sampling circuit comprises a fourth resistor R10, a fifth resistor R27 and a sixth resistor R13 connected in sequence, the free end of the fourth resistor R10 is connected to the output end of the voltage output circuit, and the free end of the sixth resistor R13 is grounded.

5. The single-chip microcomputer control-based adjustable voltage circuit according to claim 4, wherein The collector and the emitter of the phototriode OT2-A of the optical coupler OT2 are connected in parallel to the two ends of the fifth resistor R27.

6. The single-chip microcomputer control-based adjustable voltage circuit according to claim 4, wherein The reference electrode of the controllable precision voltage stabilizer U2 is connected to the connecting point between the collector of the phototriode OT2-A of the optical coupler OT2, the fourth resistor R10 and the fifth resistor R27, the cathode of the controllable precision voltage stabilizer U2 is connected to the output end of the voltage output circuit through a seventh resistor R9, and the anode of the controllable precision voltage stabilizer U2 is grounded.

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