Wide voltage, constant output power and wide output voltage linear circuit and LED lamp

Abstract

The application provides a wide voltage, constant output power and wide output voltage linear circuit, an MCU voltage detection circuit detects the voltage of input voltage dividing resistors and judges the size of the input voltage; the MCU outputs a corresponding duty ratio PWM1 signal to drive a charging switch to be turned on according to the size of the input voltage, and an electrolytic capacitor enters a charging state; the MCU voltage detection circuit also detects the voltage of output voltage dividing resistors and judges the size of the output voltage; the MCU outputs a corresponding duty ratio PWM2 signal to drive a discharging switch to be turned on according to the size of the output voltage, and the electrolytic capacitor enters a discharging state. The wide voltage, constant output power and wide output voltage linear circuit solves the problem that the traditional linear scheme cannot have a wide voltage input and the output voltage range is limited. The application also provides an LED lamp, and the driving circuit thereof is the wide voltage, constant output power and wide output voltage linear circuit.

Description

TECHNICAL FIELD

[0001] The present application relates to a lighting device, in particular to a driving circuit of the lighting device. BACKGROUND

[0002] The conventional linear scheme cannot have wide voltage input and limited output voltage range. The selection of LED light source is limited, and the finished product market is limited by voltage. It is impossible to achieve a product that can adapt to different voltage standards in different countries around the world, and it is also impossible to achieve a wide voltage unified scheme. SUMMARY

[0003] The main technical problem to be solved by the present application is to provide a wide voltage, constant output power and wide output voltage linear circuit, which solves the problem that the conventional linear scheme cannot have wide voltage input and limited output voltage range.

[0004] In order to solve the above technical problems, the present application provides a wide voltage, constant output power and wide output voltage linear circuit, which comprises an MCU voltage detection circuit, an input voltage dividing resistor, an output voltage dividing resistor, an electrolytic capacitor, a charging switch and a discharging switch.

[0005] The MCU voltage detection circuit detects the voltage of the input voltage dividing resistor and judges the size of the input voltage. The MCU outputs a PWM1 signal with a corresponding duty cycle to drive the charging switch to be turned on according to the size of the input voltage, and the electrolytic capacitor enters a charging state. The MCU voltage detection circuit also detects the voltage of the output voltage dividing resistor and judges the size of the output voltage. The MCU outputs a PWM2 signal with a corresponding duty cycle to drive the discharging switch to be turned on according to the size of the output voltage, and the electrolytic capacitor enters a discharging state.

[0006] In a preferred embodiment, the input voltage dividing resistor comprises resistors R1, R2 and R3 connected in series between the positive output end and the negative output end of the rectifier bridge; and the MCU voltage detection circuit detects the voltage of the resistor R3.

[0007] In a preferred embodiment, the output voltage dividing resistor comprises resistors R4, R5 and R6 connected in series between the positive output end and the negative output end of the rectifier bridge; and the MCU voltage detection circuit detects the voltage of the resistor R6.

[0008] In a preferred embodiment, the charging switch is a MOS tube Q1, the gate of which is connected to the PWM signal output end of the MCU, the source is connected to the negative output end of the rectifier bridge, and the drain is connected to the negative electrode of the electrolytic capacitor through a diode D1. The positive electrode of the electrolytic capacitor is connected to the positive output end of the rectifier bridge.

[0009] In a preferred embodiment: the charging switch is a MOS tube Q1, whose gate is connected to the PWM signal output terminal of the MCU, the source is connected to the negative output terminal of the rectifier bridge, the drain is connected to the negative electrode of the electrolytic capacitor, and the positive electrode of the electrolytic capacitor is connected to the positive output terminal of the rectifier bridge.

[0010] In a preferred embodiment: the discharge switch is a MOS tube Q2, whose gate is connected to the PWM signal output terminal of the MCU, the source is connected to the negative output terminal of the rectifier bridge, the drain is connected to the negative electrode of the LED through a linear IC, and the positive electrode of the LED is connected to the positive output terminal of the rectifier bridge.

[0011] In a preferred embodiment, the input voltage is 100V-264V.

[0012] In a preferred embodiment, the input voltage is 10V-90V.

[0013] The present invention further provides an LED lamp, whose driving circuit is the wide voltage, constant output power and wide output voltage linear circuit as described above.

[0014] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0015] The present invention provides a linear drive circuit with wide input voltage, constant output power, and wide output voltage. It utilizes an MCU to detect the input and output voltages, and then drives two MOS tubes through PWM to achieve controlled charging and discharging of electrolytic capacitors. This improves the problem of traditional linear solutions that cannot have a wide input voltage and the limited output voltage range. It is suitable for decorative LED lighting fixtures such as flat panel lights, ceiling lights, and downlights, and can be fully competent for any occasion, such as art galleries, museums, and other places. The scope of application includes LED lights for civil lighting, commercial lighting, industrial lighting, etc. The product is suitable for global universal mains power (100V-264V). BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a linear circuit diagram of wide voltage, constant output power and wide output voltage in preferred embodiment 1 of the present invention. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] Example 1

[0020] refer to Figure 1 , this embodiment provides a wide voltage, constant output power and wide output voltage linear circuit, including an MCU voltage detection circuit, an input voltage divider resistor, an output voltage divider resistor, an electrolytic capacitor, a charging switch and a discharging switch;

[0021] The MCU voltage detection circuit detects the voltage of the input voltage divider resistor and determines the size of the input voltage; the MCU outputs a PWM1 signal with a corresponding duty cycle according to the size of the input voltage to drive the charging switch to turn on, and the electrolytic capacitor enters the charging state; the MCU voltage detection circuit also detects the voltage of the output voltage divider resistor and determines the size of the output voltage; the MCU outputs a PWM2 signal with a corresponding duty cycle according to the size of the output voltage to drive the discharge switch to turn on, and the electrolytic capacitor enters the discharge state.

[0022] Therefore, the present invention can adjust the duty cycle of the PWM1 signal according to the input voltage, thereby achieving the purpose of adapting to different national voltages (100V-264V). Furthermore, by adjusting the duty cycle of the PWM2 signal, it can achieve different output voltages (10V-90V). This makes it suitable for decorative LED lighting fixtures such as flat panel lights, ceiling lights, and downlights, making it fully suitable for use in any occasion, such as art galleries and museums. The scope of application includes LED lighting for residential, commercial, and industrial lighting.

[0023] Specifically, in this embodiment, the input voltage divider resistors include resistors R1, R2, and R3 connected in series between the positive and negative output terminals of the rectifier bridge; the MCU voltage detection circuit detects the voltage of resistor R3. The output voltage divider resistors include resistors R4, R5, and R6 connected in series between the positive and negative output terminals of the rectifier bridge; the MCU voltage detection circuit detects the voltage of resistor R6.

[0024] The charging switch is a MOS transistor Q1, whose gate is connected to the PWM signal output of the MCU, its source is connected to the negative output terminal of the rectifier bridge, and its drain is connected to the negative terminal of the electrolytic capacitor through a diode D1. The positive terminal of the electrolytic capacitor is connected to the positive output terminal of the rectifier bridge. When Q1 is turned on, the two ends of the electrolytic capacitor are connected to the positive and negative output terminals of the rectifier bridge, charging the electrolytic capacitor.

[0025] The discharge switch is a MOS transistor Q2, whose gate is connected to the PWM signal output of the MCU, its source is connected to the negative output terminal of the rectifier bridge, and its drain is connected to the negative terminal of the LED through a linear IC. The positive terminal of the LED is connected to the positive output terminal of the rectifier bridge. In this way, when Q2 is turned on, the two ends of the electrolytic capacitor are connected to the two ends of the LED, realizing the discharge of the electrolytic capacitor.

[0026] The present invention provides an LED lamp, whose driving circuit is the above-mentioned wide voltage, constant output power and wide output voltage linear circuit.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. Wide voltage, constant output power and wide output voltage linear circuit, characterized by: Includes MCU voltage detection circuit, input voltage divider resistor, output voltage divider resistor, electrolytic capacitor, charging switch and discharging switch; The MCU voltage detection circuit detects the voltage of the input voltage divider resistor and determines the magnitude of the input voltage; the MCU outputs a PWM1 signal corresponding to the duty cycle according to the magnitude of the input voltage to drive the charging switch to turn on, and the electrolytic capacitor enters a charging state; The MCU voltage detection circuit also detects the voltage of the output voltage divider resistor and determines the magnitude of the output voltage; the MCU outputs a PWM2 signal corresponding to the duty cycle according to the magnitude of the output voltage to drive the discharge switch to turn on, and the electrolytic capacitor enters the discharge state; The charging switch is a MOS tube Q1, whose gate is connected to the PWM signal output terminal of the MCU, the source is connected to the negative output terminal of the rectifier bridge, the drain is connected to the negative electrode of the electrolytic capacitor through a diode D1, and the positive electrode of the electrolytic capacitor is connected to the positive output terminal of the rectifier bridge; the discharging switch is a MOS tube Q2, whose gate is connected to the PWM signal output terminal of the MCU, the source is connected to the negative output terminal of the rectifier bridge, and the source is also connected to the negative electrode of the electrolytic capacitor through a diode D2; the drain is connected to the negative electrode of the LED through a linear IC, and the positive electrode of the LED is connected to the positive output terminal of the rectifier bridge.

2. The wide voltage, constant output power and wide output voltage linear circuit according to claim 1, characterized in that: The input voltage-dividing resistor includes resistors R1, R2, and R3 connected in series between the positive output terminal and the negative output terminal of the rectifier bridge; the MCU voltage detection circuit detects the voltage of the resistor R3.

3. The wide voltage, constant output power and wide output voltage linear circuit according to claim 1, characterized in that: The output voltage divider resistor includes resistors R4, R5, and R6 connected in series between the positive output terminal and the negative output terminal of the rectifier bridge; the MCU voltage detection circuit detects the voltage of the resistor R6.

4. The wide voltage, constant output power and wide output voltage linear circuit according to claim 1, characterized in that: The input voltage is 100V-264V.

5. The wide voltage, constant output power and wide output voltage linear circuit according to claim 1, characterized in that: The output voltage is 10V-90V.

6. An LED lamp, characterized in that The driving circuit is a wide voltage, constant output power and wide output voltage linear circuit as described in any one of claims 1 to 5.

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