A control circuit for reducing power consumption of a fantasy color lamp strip when it is turned off

Abstract

The utility model discloses a control circuit that reduces the power consumption of the illusory color lamp area when it is extinguished, including DCDC voltage reducing module and low -power module, DCDC voltage reducing module includes: DCDC chip is used for reducing the input voltage of outside to output voltage, and output voltage is used to provide the voltage required for the work of illusory color lamp area and MCU, and MCU is used for controlling the bright of illusory color lamp area and extinguish, a plurality of series first voltage division resistance, and first voltage division resistance is used for adjusting output voltage value, low -power module includes: switch spare, by MCU control, is used for controlling second voltage division resistance conduction or cut -off, second voltage division resistance is parallel with at least one resistance in first voltage division resistance, is used for reducing output voltage value when cut -off. The scheme can pick illusory color lamp area extinguished state, and the output voltage is adjusted through low -power module, and the power consumption is reduced greatly, and the energy waste is avoided.

Description

Technical Field

[0001] This utility model relates to the field of lighting equipment control technology, and in particular to a control circuit for reducing the power consumption of a RGB LED strip when it is turned off. Background Technology

[0002] With the development of LED lighting technology, RGB LED strips, due to their rich colors and dynamic adjustability, are widely used in decorative lighting, landscape lighting, and home ambiance creation. The normal operation of RGB LED strips relies on a stable power supply system and precise control circuitry, with the design of the power supply circuit directly affecting the strip's power consumption, stability, and lifespan.

[0003] In existing technologies, the control circuit of iridescent LED strips typically uses a DC / DC step-down module to provide operating voltage for the LED strip and control unit. Traditional solutions have the following problems: excessive power consumption in non-operating states: when the LED strip is off, if the circuit is continuously powered by the operating voltage, even if the LED strip is not emitting light, the circuit will still generate additional power consumption to maintain a high voltage output, especially during long standby or off states, resulting in significant energy waste. Utility Model Content

[0004] The purpose of this invention is to overcome the defect of high power consumption when the LED strip is turned off in the existing technology of LED strip control, and to provide a control circuit that reduces the power consumption of the LED strip when it is turned off.

[0005] The objective of this utility model is achieved through the following technical solution: A control circuit for reducing the power consumption of a RGB LED strip when it is off includes a DC / DC step-down module and a low-power module. The DC / DC step-down module includes: The DC / DC chip is used to step down the external input voltage to the output voltage. The output voltage is used to provide the voltage required for the operation of the LED strip and the MCU. The MCU is used to control the lighting of the LED strip. Several first voltage divider resistors connected in series are used to adjust the output voltage value. The low-power module includes: The switching device, controlled by the MCU, is used to control the second voltage divider resistor to be turned on or off; The second voltage divider resistor, connected in parallel with at least one of the first voltage divider resistors, is used to reduce the output voltage value when cut off.

[0006] Preferably, the IN pin of the DC / DC chip is connected to the input power supply, and the GND pin of the DC / DC chip is grounded; the first voltage divider resistor includes resistor R1 and resistor R2, the FB pin of the DC / DC chip is connected to one end of both resistor R1 and resistor R2, the other end of resistor R1 is connected to the SW pin of the DC / DC chip through inductor R1, the other end of resistor R2 is grounded, and the other end of resistor R1 is the output power supply terminal; the FB pin of the DC / DC chip is also connected to the low-power module.

[0007] Preferably, a capacitor C2 is provided between the input power supply and the ground, and a capacitor C3 is provided between the output power supply and the ground. Both capacitors C2 and C3 are filter capacitors.

[0008] Preferably, a capacitor C1 is provided between the BS pin of the DC / DC chip and the output power supply, an inductor L1 is provided between the SW pin of the DC / DC chip and the output power supply, and a freewheeling diode D1 is provided between the SW pin of the DC / DC chip and ground. The capacitor C1, inductor L1 and freewheeling diode D1 are used to ensure the stability of the output power supply voltage.

[0009] Preferably, the switching device is a field-effect transistor Q1.

[0010] Preferably, the gate of the field-effect transistor Q1 is connected to the MCU, the source of the field-effect transistor Q1 is grounded, the drain of the field-effect transistor Q1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to the FB pin of the DC / DC chip.

[0011] Preferably, the low-power module further includes a delay unit connected in series between the MCU and the switching device. The delay unit is used to delay the switching device for a set time after the MCU detects the light strip extinguishing signal, so as to prevent malfunction caused by the instantaneous extinguishing signal.

[0012] Preferably, the output voltage is 12V when the second voltage divider resistor is on and 6.4V when the second voltage divider resistor is off.

[0013] The beneficial effects of this utility model are: this solution can significantly reduce power consumption and avoid energy waste by adjusting the output voltage through a low-power module when the LED strip is off; by reducing the power supply voltage instead of cutting off the power supply, the flickering problem when the LED strip is powered on again is avoided, thus improving the user experience; this solution does not require complex structures or high-cost components, thus balancing cost and stability and helping to enhance product lifespan. Attached Figure Description

[0014] Figure 1 This is a circuit diagram of this utility model; Figure 2This is a circuit diagram of a light strip control in the prior art; Figure 3 This is a circuit diagram of another type of LED strip control in the existing technology. Detailed Implementation

[0015] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0016] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0017] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0018] Example: A control circuit for reducing power consumption of RGB LED strips when they are turned off, such as... Figure 1 As shown, it includes a DC / DC step-down module and a low-power module. The DC / DC step-down module includes: The DC / DC chip is used to step down the external input voltage to the output voltage. The output voltage is used to provide the voltage required for the operation of the LED strip and the MCU. The MCU is used to control the lighting of the LED strip. Several first voltage divider resistors connected in series are used to adjust the output voltage value. The low-power module includes: The switching device, controlled by the MCU, is used to control the second voltage divider resistor to be turned on or off; The second voltage divider resistor, connected in parallel with at least one of the first voltage divider resistors, is used to reduce the output voltage value when cut off.

[0019] The IN pin of the DC / DC chip is connected to the input power supply, and the GND pin of the DC / DC chip is grounded. The first voltage divider resistor includes resistors R1 and R2. The FB pin of the DC / DC chip is connected to one end of both resistors R1 and R2. The other end of resistor R1 is connected to the SW pin of the DC / DC chip through inductor R1. The other end of resistor R2 is grounded, and the other end of resistor R1 is the output power supply terminal. The FB pin of the DC / DC chip is also connected to the low-power module.

[0020] A capacitor C2 is provided between the input power supply and the ground, and a capacitor C3 is provided between the output power supply and the ground. Both capacitors C2 and C3 are filter capacitors.

[0021] A capacitor C1 is provided between the BS pin of the DC / DC chip and the output power supply. An inductor L1 is also provided between the SW pin of the DC / DC chip and the output power supply. A freewheeling diode D1 is also provided between the SW pin of the DC / DC chip and ground. The capacitor C1, inductor L1 and freewheeling diode D1 are used to ensure the stability of the output power supply voltage.

[0022] The switching device is a field-effect transistor Q1.

[0023] The gate of the field-effect transistor Q1 is connected to the MCU, the source of the field-effect transistor Q1 is grounded, the drain of the field-effect transistor Q1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to the FB pin of the DC / DC chip.

[0024] Existing methods for implementing RGB LED strips generally fall into two categories: those with built-in LED chips and those with external chips. This invention addresses the issue of external chip-based solutions. To achieve good display effects for longer LED strips, external chip solutions with a power supply voltage greater than 5V are typically used, such as 12V or 24V (hereinafter referred to as high voltage).

[0025] The typical power supply voltage for chips is around 5V. Therefore, high-voltage power supply LED strips usually have a simple step-down circuit to reduce the high voltage to around 5V to power the chip. A voltage of around 5V is obtained through the external resistor and the internal Zener diode of the chip.

[0026] A 12V LED strip typically has a resistance of 510 ohms, while a 24V LED strip typically has a resistance of 1 kΩ. Therefore, P(12V) = 0.165W; P(24V) = 0.456W. This is the power consumption of each group. Since LED strips consist of many groups, a standard 12V LED strip has 20 groups per meter, and a standard 24V LED strip has 10 groups per meter. Multiplying the power of each group by the number of groups gives us 3.3W per meter for a 12V LED strip and 4.56W per meter for a 24V LED strip. Considering the losses in the voltage reduction circuit when the LED strip is off, it's clear that the current circuit has relatively high power consumption.

[0027] In this scheme, when the field-effect transistor Q1 is controlled by resistor R3 and is turned off, the output voltage V OUT The calculation formula is: V out =V FB / R2*(R1+R2) V FB Determined by the DC / DC chip, the LED strip is currently off.

[0028] When the field-effect transistor Q1 is controlled by resistor R3, the output voltage V OUT The calculation formula is: The output voltage V is changed by using an additional resistor R3 and a field-effect transistor Q1. OUT After the field-effect transistor Q1 is turned on, it is equivalent to resistor R3 connected in parallel with resistor R2, thereby increasing V. OUT At this time, the LED strip is illuminated.

[0029] Meanwhile, the LED strip control needs to be implemented by an MCU. When the system power supply is greater than the rated voltage of the LED strip, two independent step-down circuits are generally selected to power the LED strip and the MCU respectively, such as... Figure 2 As shown. However, for the MCU's step-down power supply section, this solution requires more space and materials if a DC-DC converter is chosen, while an LDO requires high-voltage components and will also bring considerable losses and heat generation. Therefore, a high-power DC-DC converter is chosen to power the LED strip, and a low-power LDO is connected in series to power the MCU (e.g., Figure 3 The solution shown is a suitable low-cost option.

[0030] Regarding Solution 1 above, when the light strip is not lit, the MCU can control the power supply circuit of the disabled light strip to stop supplying power to the light strip, thereby reducing power consumption. However, some light strips on the market have a default lighting mode after power-on, which may cause the MCU to be unable to control the light strip for a moment when the power supply is disabled, resulting in the light strip flickering. For Solution 2, it is not possible to disable the power supply circuit of the light strip through the MCU, because the MCU's power supply is provided by the light strip's power supply. Controlling the light strip's power supply through the MCU would result in two problems: firstly, there is a power-on self-locking issue preventing restarting; secondly, after a power failure, the MCU would lose power and be unable to control restarting.

[0031] This embodiment addresses Scheme 2, which reduces the power supply voltage instead of continuously turning off the LED strip power supply, ensuring that the MCU can work normally while significantly reducing the power consumption of the LED strip when it is not emitting light.

[0032] Specifically, by configuring resistors R1, R2, and R3, V is adjusted when the field-effect transistor Q1 is turned on. OUT When the output is 12V and the MOSFET Q1 is off, V OUTThe output is 6.4V. Because 6.4V is greater than the MCU supply voltage (5V) plus the LDO voltage difference (generally less than 1V), it will not affect the normal power supply of the MCU. However, for the LED strip, the power supply is reduced from 12V to 6.4V, resulting in a calculated loss of 0.351W per meter, less than one-ninth of the original. If the MCU supports 3.3V power supply, the resistance value can be optimized appropriately. OUT The voltage can be lowered, and the power consumption can be further reduced.

[0033] Example 2: A control circuit for reducing the power consumption of a RGB LED strip when it is turned off. Its principle and implementation method are basically the same as those of Example 1. The difference is that the low-power module also includes a delay unit. The delay unit is connected in series between the MCU and the switching device. It is used to delay the switching device for a set time after the MCU detects the LED strip turning off signal, so as to prevent malfunction caused by the instantaneous turning off signal.

[0034] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0035] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A control circuit for reducing power consumption of a color-changing LED strip when it is turned off, characterized in that, It includes a DC / DC step-down module and a low-power module, wherein the DC / DC step-down module includes: The DC / DC chip is used to step down the external input voltage to the output voltage. The output voltage is used to provide the voltage required for the operation of the LED strip and the MCU. The MCU is used to control the lighting of the LED strip. Several first voltage divider resistors connected in series are used to adjust the output voltage value. The low-power module includes: The switching device, controlled by the MCU, is used to control the second voltage divider resistor to be turned on or off; The second voltage divider resistor, connected in parallel with at least one of the first voltage divider resistors, is used to reduce the output voltage value when cut off.

2. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 1, is characterized in that... The IN pin of the DC / DC chip is connected to the input power supply, and the GND pin of the DC / DC chip is grounded. The first voltage divider resistor includes resistors R1 and R2. The FB pin of the DC / DC chip is connected to one end of both resistors R1 and R2. The other end of resistor R1 is connected to the SW pin of the DC / DC chip through inductor R1. The other end of resistor R2 is grounded, and the other end of resistor R1 is the output power supply terminal. The FB pin of the DC / DC chip is also connected to the low-power module.

3. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 2, is characterized in that... A capacitor C2 is provided between the input power supply and the ground, and a capacitor C3 is provided between the output power supply and the ground. Both capacitors C2 and C3 are filter capacitors.

4. A control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 2 or 3, characterized in that... A capacitor C1 is provided between the BS pin of the DC / DC chip and the output power supply. An inductor L1 is also provided between the SW pin of the DC / DC chip and the output power supply. A freewheeling diode D1 is also provided between the SW pin of the DC / DC chip and ground. The capacitor C1, inductor L1 and freewheeling diode D1 are used to ensure the stability of the output power supply voltage.

5. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 2, is characterized in that... The switching device is a field-effect transistor Q1.

6. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 5, is characterized in that... The gate of the field-effect transistor Q1 is connected to the MCU, the source of the field-effect transistor Q1 is grounded, the drain of the field-effect transistor Q1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to the FB pin of the DC / DC chip.

7. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 1, is characterized in that... The low-power module also includes a delay unit connected in series between the MCU and the switching device. The delay unit is used to control the switching device to turn off after the MCU detects the light strip turning off signal and delays for a set time.

8. The control circuit for reducing power consumption of a RGB LED strip when it is turned off, as described in claim 1, is characterized in that... The output voltage is 12V when the second voltage divider resistor is on and 6.4V when the second voltage divider resistor is off.

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