LED drive circuit with main lamp and night lamp conversion function

Abstract

The utility model discloses an LED drive circuit with a main lamp and night lamp conversion function, which relates to the technical field of LED drive power supplies and comprises a main power supply, a main lamp and night lamp conversion circuit, a night lamp and night lamp conversion circuit, a main lamp and night lamp conversion circuit, and a night lamp and night lamp conversion circuit, and is characterized in that the main power supply is used for introducing 220V alternating current, converting the 220V alternating current into adjustable direct current and outputting the adjustable direct current to the main lamp and night lamp conversion circuit; and the main lamp and night lamp conversion circuit is used for controlling the main lamp to emit light or the night lamp to emit light according to the on-off of the alternating current input by the main power supply. Compared with the prior art, the main lamp and night lamp conversion circuit and the main lamp and night lamp output current control circuit are optimized; a main power supply output is used for supplying power to an MCU (chip U2) through voltage reduction of a voltage stabilizer LDO, MCU power supply when the mains supply is closed is temporarily maintained based on the energy storage effect of a capacitor EC1, and meanwhile, after a main night lamp is switched, the impedance of a main night lamp output current control circuit can be automatically changed, and the current magnitude is changed.

Description

Technical Field

[0001] The utility model relates to the technical field of LED drive power supply, in particular to an LED drive circuit with main light and night light conversion. Background Art

[0002] As people's living standards improve, their requirements for home environment are getting higher and higher. As a kind of lamp that can create a warm atmosphere, the market demand for night lights is also increasing, and it still has a very broad market prospect. There is also an increasing demand to integrate night lights with main lights.

[0003] Currently, the power supply solutions on the market use MCU to detect the input AC voltage to control the switching of the main light and the night light. This type of control requires that the MCU maintain power supply after the input is turned off in order to process the detection circuit signal. This requires additional circuits to power the MCU and maintain the power supply voltage for a corresponding period of time.

[0004] The existing main light and night light switching increases the difficulty and cost of the design and needs to be improved. Utility Model Content

[0005] The purpose of the utility model is to provide an LED driving circuit with main light and night light conversion to solve the problems raised in the above background technology.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] An LED driving circuit with main light and night light conversion, comprising:

[0008] Main power supply, used to convert 220V AC power into adjustable DC power and output it to the main light and night light conversion circuit;

[0009] The main light and night light conversion circuit is used to control the main light or the night light to emit light according to the on and off of the AC power input from the main power supply, and at the same time provide a control signal to the main light and night light output current control circuit;

[0010] The main night light output current control circuit is used to provide an impedance to the main power supply, and when receiving a control signal, the impedance size is changed, and based on different impedances, the output DC power size of the main power supply is changed;

[0011] The output end of the main power supply is connected to the input end of the main night light conversion circuit, the output end of the main night light conversion circuit is connected to the input end of the main night light output current control circuit, and the output end of the main night light output current control circuit is connected to the current detection end of the main power supply.

[0012] As a further solution of the utility model: the main power supply includes a rectifier BD1, a chip U1, a transformer T1, a diode D1, a capacitor EC1, a capacitor C1, a capacitor C2, a resistor R1, and a MOS tube Q3. The first end of the rectifier BD1 is connected to the live wire L, the third end of the rectifier BD1 is connected to the neutral wire N, the second end of the rectifier BD1 is grounded, the fourth end of the rectifier BD1 is connected to one end of the capacitor C1, one end of the resistor R1, and one end of the input end of the transformer T1. The other end of the capacitor C1 is grounded, and the other end of the resistor R1 is connected to one end of the capacitor C2 and the No. 1 lead of the chip U1. Pin, the other end of capacitor C2 is grounded, the other end of the input end of transformer T1 is connected to the D pole of MOS tube Q3, the G pole of MOS tube Q3 is connected to pin 6 of chip U1, the S pole of MOS tube Q3 is connected to pin 5 of chip U1, pin 4 of chip U1 is connected to the output end of the main light night light output current control circuit, one end of the output end of transformer T is connected to the common point A, the other end of the output end of transformer T1 is connected to the positive pole of diode D1, the negative pole of diode D1 is connected to one end of capacitor EC1 and the input end of the main light night light conversion circuit, and the other end of capacitor EC1 is connected to the common point A.

[0013] As a further solution of the utility model: the main light and night light conversion circuit includes a main light, a night light, a MOS tube Q1, a MOS tube Q2, a chip U2, a diode D2, and a capacitor C3. The positive pole of the main light is connected to the positive pole of the night light and the output end of the main power supply. The negative pole of the main light is connected to the D pole of the MOS tube Q1, the negative pole of the night light is connected to the D pole of the MOS tube Q2, the S pole of the MOS tube Q1 is connected to the common point A, the S pole of the MOS tube Q2 is connected to the common point A, the G pole of the MOS tube Q1 is connected to the pin No. 6 of the chip U2, the G pole of the MOS tube Q2 is connected to the pin No. 5 of the chip U2, and the main light and night light output current control circuit. Pin No. 7 of the chip U2 is connected to the negative pole of the diode D2 and one end of the capacitor C3, the positive pole of the diode D2 is connected to the output end of the main power transformer T1, and the other end of the capacitor C3 is connected to the common point A.

[0014] As a further solution of the utility model: the main light night light conversion circuit also includes a voltage regulator LDO and a capacitor EC2. The input end of the voltage regulator LDO is connected to the output end of the main power supply, the ground end of the voltage regulator LDO is connected to the common point A, the output end of the voltage regulator LDO is connected to one end of the capacitor EC2, and the other end of the capacitor EC2 is grounded. The output end of the voltage regulator LDO outputs a 5V voltage as the working power supply of the chip U2.

[0015] As a further solution of the utility model: the main night light output current control circuit includes resistor R2, resistor R3, MOS tube Q4, resistor R4, resistor R5, MOS tube Q5, and optocoupler U3. One end of resistor R2 is connected to one end of resistor R3 and the current detection end of the main power supply, the other end of resistor R2 is grounded, the other end of resistor R3 is connected to the D pole of MOS tube Q4, the S pole of MOS tube Q4 is grounded, the G pole of MOS tube Q4 is connected to one end of resistor R4 and the fourth end of optocoupler U3, the other end of resistor R4 is connected to the power supply voltage VCC, the third end of optocoupler U3 is grounded, the first end of optocoupler U3 is connected to the output end of the main power supply through resistor R5, the second end of optocoupler U3 is connected to the D pole of MOS tube Q5, the S pole of MOS tube Q5 is grounded, and the G pole of MOS tube Q5 is connected to the control signal end of the main night light conversion circuit.

[0016] Compared with the prior art, the beneficial effects of the utility model are as follows: the utility model optimizes the main night light conversion circuit and the main night light output current control circuit, utilizes the main power output to step down the voltage through the voltage regulator LDO to power the MCU (here is the chip U2), and based on the energy storage effect of capacitor EC1, briefly maintains the power supply to the MCU when the AC power is turned off; at the same time, after the main night light is switched, the impedance of the main night light output current control circuit will automatically change, thereby changing the current size. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a circuit diagram of an LED driving circuit with main light and night light conversion. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0019] See also Figure 1 , an LED driving circuit with main light and night light conversion, comprising:

[0020] Main power supply, used to convert 220V AC power into adjustable DC power and output it to the main light and night light conversion circuit;

[0021] The main light and night light conversion circuit is used to control the main light or the night light to emit light according to the on and off of the AC power input from the main power supply, and at the same time provide a control signal to the main light and night light output current control circuit;

[0022] The main night light output current control circuit is used to provide a signal to the main power supply, and when receiving the control signal, the impedance size is changed, and based on different impedances, the output DC power size of the main power supply is changed;

[0023] The output end of the main power supply is connected to the input end of the main night light conversion circuit, the output end of the main night light conversion circuit is connected to the input end of the main night light output current control circuit, and the output end of the main night light output current control circuit is connected to the current detection end of the main power supply.

[0024] In this example: See Figure 1 The main power supply includes a rectifier BD1, a chip U1, a transformer T1, a diode D1, a capacitor EC1, a capacitor C1, a capacitor C2, a resistor R1, and a MOS tube Q3. The first end of the rectifier BD1 is connected to the live wire L, the third end of the rectifier BD1 is connected to the neutral wire N, the second end of the rectifier BD1 is grounded, the fourth end of the rectifier BD1 is connected to one end of the capacitor C1, one end of the resistor R1, and one end of the input end of the transformer T1. The other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected to one end of the capacitor C2 and the No. 1 pin of the chip U1, and the No. 1 pin of the capacitor C2. The other end is grounded, the other end of the input end of the transformer T1 is connected to the D pole of the MOS tube Q3, the G pole of the MOS tube Q3 is connected to the No. 6 pin of the chip U1, the S pole of the MOS tube Q3 is connected to the No. 5 pin of the chip U1, the No. 4 pin of the chip U1 is connected to the output end of the main light night light output current control circuit, one end of the output end of the transformer T is connected to the common point A, the other end of the output end of the transformer T1 is connected to the positive pole of the diode D1, the negative pole of the diode D1 is connected to one end of the capacitor EC1 and the input end of the main light night light conversion circuit, and the other end of the capacitor EC1 is connected to the common point A.

[0025] The AC power supply is input through the live wire L and the neutral wire N, and the conduction state of the MOS tube Q3 is controlled by the chip U1 to control the current on the transformer T1. By changing the impedance at pin 4 of the chip U1, the conduction state of the MOS tube Q3 can be changed, and finally the current output to the main light night light conversion circuit is controlled.

[0026] In this example: See Figure 1The main light and night light conversion circuit includes a main light, a night light, a MOS tube Q1, a MOS tube Q2, a chip U2, a diode D2, and a capacitor C3. The positive pole of the main light is connected to the positive pole of the night light and the output end of the main power supply. The negative pole of the main light is connected to the D pole of the MOS tube Q1, the negative pole of the night light is connected to the D pole of the MOS tube Q2, the S pole of the MOS tube Q1 is connected to the common point A, the S pole of the MOS tube Q2 is connected to the common point A, the G pole of the MOS tube Q1 is connected to the No. 6 pin of the chip U2, the G pole of the MOS tube Q2 is connected to the No. 5 pin of the chip U2, and the main light and night light output current control circuit. The No. 7 pin of the chip U2 is connected to the negative pole of the diode D2 and one end of the capacitor C3. The positive pole of the diode D2 is connected to the output end of the main power transformer T1, and the other end of the capacitor C3 is connected to the common point A.

[0027] In this example: See Figure 1 The main light night light conversion circuit also includes a voltage regulator LDO and a capacitor EC2. The input end of the voltage regulator LDO is connected to the output end of the main power supply, the ground end of the voltage regulator LDO is connected to the common point A, the output end of the voltage regulator LDO is connected to one end of the capacitor EC2, and the other end of the capacitor EC2 is grounded. The output end of the voltage regulator LDO outputs a 5V voltage as the working power supply of the chip U2.

[0028] After the main power supply voltage is input, the pin 7 of chip U2 receives the voltage, the pin 6 outputs a high level, and the pin 5 outputs a low level, which controls the MOS tube Q1 to be turned on, and the main light illuminates. When the user needs to switch the night light, the power supply is first disconnected, and then restored (the existing technology is to first disconnect the power, and then restore the power to complete the switching of the main light and the night light, and the chip U2 needs an additional power supply to ensure that the chip U2 can maintain operation when the power is off). At this time, based on the energy storage effect of capacitor EC1, the output can be maintained for 5 seconds when the main power input is turned off to supply power to the voltage regulator LDO, and the voltage regulator LDO maintains a 5V voltage to supply power to the chip U2. After the switch is completed, the voltage on the pin 7 of chip U2 becomes a high level again (the change process is high level, low level, high level), and the pin 6 is controlled to output a low level, and the pin 5 is output a high level. At this time, the MOS tube Q2 is turned on, and the night light illuminates.

[0029] In this example: See Figure 1The main night light output current control circuit includes a resistor R2, a resistor R3, a MOS tube Q4, a resistor R4, a resistor R5, a MOS tube Q5, and an optocoupler U3. One end of the resistor R2 is connected to one end of the resistor R3 and the current detection end of the main power supply. The other end of the resistor R2 is grounded. The other end of the resistor R3 is connected to the D pole of the MOS tube Q4, the S pole of the MOS tube Q4 is grounded, the G pole of the MOS tube Q4 is connected to one end of the resistor R4 and the fourth end of the optocoupler U3. The other end of the resistor R4 is connected to the power supply voltage VCC, the third end of the optocoupler U3 is grounded, the first end of the optocoupler U3 is connected to the output end of the main power supply through the resistor R5, the second end of the optocoupler U3 is connected to the D pole of the MOS tube Q5, the S pole of the MOS tube Q5 is grounded, and the G pole of the MOS tube Q5 is connected to the control signal end of the main night light conversion circuit.

[0030] When the main light is on, MOS tube Q5 and optocoupler U3 are cut off, MOS tube Q4 is fully turned on, the impedance of pin 4 of chip U1 is small, and the output current is large.

[0031] When the night light is on, the G terminal of MOS tube Q5 is at a high level, MOS tube Q5 is turned on, and then the optocoupler U3 is turned on, MOS tube Q4 is turned off, and the impedance of pin 4 of chip U1 is large, which makes the output current of the main power supply smaller.

[0032] The working principle of the utility model is: the main power supply is used to introduce 220V alternating current and convert it into adjustable direct current, and output it to the main light and night light conversion circuit; the main light and night light conversion circuit is used to control the main light or the night light to emit light according to the on and off of the alternating current input by the main power supply, and at the same time provide a control signal to the main light and night light output current control circuit; the main light and night light output current control circuit is used to provide a signal to the main power supply, and when receiving the control signal, the impedance size is changed, and based on different impedances, the output direct current size of the main power supply is changed.

[0033] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, the embodiments should be considered as exemplary and non-restrictive in all respects.

[0034] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An LED driving circuit with main light and night light conversion, characterized in that: The LED driving circuit with main light and night light conversion includes: Main power supply, used to convert 220V AC power into adjustable DC power and output it to the main light and night light conversion circuit; The main light and night light conversion circuit is used to control the main light or the night light to emit light according to the on and off of the AC power input from the main power supply, and at the same time provide a control signal to the main light and night light output current control circuit; The main night light output current control circuit is used to provide a signal to the main power supply, and when receiving the control signal, the impedance size is changed, and based on different impedances, the output DC power size of the main power supply is changed; The output end of the main power supply is connected to the input end of the main night light conversion circuit, the control signal of the main night light conversion circuit is connected to the input end of the main night light output current control circuit, and the output end of the main night light output current control circuit is connected to the current detection end of the main power supply.

2. The LED driving circuit with main light and night light conversion according to claim 1, characterized in that: The main power supply includes a rectifier BD1, a chip U1, a transformer T1, a diode D1, a capacitor EC1, a capacitor C1, a capacitor C2, a resistor R1, and a MOS tube Q3. The first end of the rectifier BD1 is connected to the live wire L, the third end of the rectifier BD1 is connected to the neutral wire N, the second end of the rectifier BD1 is grounded, the fourth end of the rectifier BD1 is connected to one end of the capacitor C1, one end of the resistor R1, and one end of the input end of the transformer T1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected to one end of the capacitor C2 and the No. 1 pin of the chip U1, and the other end of the capacitor C2 is grounded. One end is grounded, the other end of the input end of the transformer T1 is connected to the D pole of the MOS tube Q3, the G pole of the MOS tube Q3 is connected to the No. 6 pin of the chip U1, the S pole of the MOS tube Q3 is connected to the No. 5 pin of the chip U1, the No. 4 pin of the chip U1 is connected to the output end of the main light night light output current control circuit, one end of the output end of the transformer T is connected to the common point A, the other end of the output end of the transformer T1 is connected to the positive pole of the diode D1, the negative pole of the diode D1 is connected to one end of the capacitor EC1 and the input end of the main light night light conversion circuit, and the other end of the capacitor EC1 is connected to the common point A.

3. The LED driving circuit with main light and night light conversion according to claim 1, characterized in that: The main light and night light conversion circuit includes a main light, a night light, a MOS tube Q1, a MOS tube Q2, a chip U2, a diode D2, and a capacitor C3. The positive pole of the main light is connected to the positive pole of the night light and the output end of the main power supply. The negative pole of the main light is connected to the D pole of the MOS tube Q1, the negative pole of the night light is connected to the D pole of the MOS tube Q2, the S pole of the MOS tube Q1 is connected to the common point A, the S pole of the MOS tube Q2 is connected to the common point A, the G pole of the MOS tube Q1 is connected to the No. 6 pin of the chip U2, the G pole of the MOS tube Q2 is connected to the No. 5 pin of the chip U2, and the main light and night light output current control circuit. The No. 7 pin of the chip U2 is connected to the negative pole of the diode D2 and one end of the capacitor C3. The positive pole of the diode D2 is connected to the output end of the main power transformer T1, and the other end of the capacitor C3 is connected to the common point A.

4. The LED driving circuit with main light and night light conversion according to claim 3, characterized in that: The main light night light conversion circuit also includes a voltage regulator LDO and a capacitor EC2. The input end of the voltage regulator LDO is connected to the output end of the main power supply, the ground end of the voltage regulator LDO is connected to the common point A, the output end of the voltage regulator LDO is connected to one end of the capacitor EC2, and the other end of the capacitor EC2 is grounded. The output end of the voltage regulator LDO outputs a 5V voltage as the working power supply of the chip U2.

5. The LED driving circuit with main light and night light conversion according to claim 1, characterized in that: The main night light output current control circuit includes a resistor R2, a resistor R3, a MOS tube Q4, a resistor R4, a resistor R5, a MOS tube Q5, and an optocoupler U3. One end of the resistor R2 is connected to one end of the resistor R3 and the current detection end of the main power supply, the other end of the resistor R2 is grounded, the other end of the resistor R3 is connected to the D pole of the MOS tube Q4, the S pole of the MOS tube Q4 is grounded, the G pole of the MOS tube Q4 is connected to one end of the resistor R4 and the fourth end of the optocoupler U3, the other end of the resistor R4 is connected to the power supply voltage VCC, the third end of the optocoupler U3 is grounded, the first end of the optocoupler U3 is connected to the output end of the main power supply through the resistor R5, the second end of the optocoupler U3 is connected to the D pole of the MOS tube Q5, the S pole of the MOS tube Q5 is grounded, and the G pole of the MOS tube Q5 is connected to the control signal end of the main night light conversion circuit.

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