Constant voltage light strip driver based on constant current power supply with configurable output current

Abstract

The present invention relates to a constant voltage light strip driving device based on a constant current power supply with configurable output current, comprising a constant current power supply, a driver and a light strip, wherein the constant current power supply is connected to the light strip through the driver, and the light strip is a constant voltage light strip or a constant current light strip; the device adopts a combination of a constant current dimming power supply and a constant voltage light strip, and can obtain a good dimming effect at high and low brightness. Compared with the prior art, the present invention has the advantages of maintaining the consistency of the brightness of the constant voltage light strip driven by the constant voltage dimming power supply under long-distance high brightness conditions, and having the advantages of good brightness consistency of the constant current dimming power supply driving the constant current light strip under low brightness conditions.

Description

Technical Field

[0001] The present invention relates to an LED light strip driving device, and in particular to a constant voltage light strip driving device based on a constant current power supply with configurable output current. Background Art

[0002] At present, the LED light strips on the market can be divided into constant voltage LED light strips and constant current LED light strips according to the driving mode. Constant voltage LED light strips are suitable for constant voltage dimming power supplies. The light strip specifications include DC12V, 24V, 36V, 48V, etc. The output voltage of the power supply needs to be pre-matched with the voltage of the light strip; constant current LED light strips are suitable for constant current dimming power supplies. The power supply can be freely configured according to the current specifications of the light strip.

[0003] Since the light strip transmits current through the transmission line, there will be line loss regardless of the constant current or constant voltage mode (line loss is the voltage loss on the line). The longer the transmission distance, the greater the transmission current, and the greater the line loss.

[0004] The dimming scheme of the constant voltage dimming power supply is: the voltage amplitude of the rectangular wave output by the power port remains unchanged, and the brightness is changed by adjusting the duty cycle of the rectangular wave. Line loss only exists when there is current on the line, that is, when the rectangular wave is high.

[0005]

[0006] Since line loss is related to the physical characteristics of the transmission line and the instantaneous current on the transmission line, once the LED light strip is installed, the line loss of each LED is fixed and unchanged. When the light strip is at high brightness, although the current amplitude of each LED is different, the human eye is not sensitive to the brightness difference between LEDs at high brightness; at low brightness, the high-level duty cycle of the rectangular wave becomes smaller, although the current amplitude of each LED is different as at high brightness, the brightness difference between LEDs on the light strip is extremely obvious due to the high sensitivity of the human eye to low brightness. Figure 1 Generally, the maximum length of a LED light strip with single-end power supply is only 10 meters (double-end power supply can reach 20 meters).

[0007] The dimming scheme of the constant current dimming power supply is to dim the light by controlling the amplitude of the output current. Similarly, when the brightness is high, the output current is large and the line loss is also large.

[0008]

[0009] The dynamic resistance r of the lamp bead increases sharply as the voltage across the LED decreases. At high brightness, the voltage across the LEDs of the lamp bead at the far end of the constant current LED strip decreases due to large line loss, the internal resistance increases, and the LED current drops sharply. The human eye is not sensitive to high brightness differences, so the brightness difference of each LED is not obvious. At low brightness, since the power output is low-pulsation DC, the line loss is very small, and the voltage of each LED on the light strip is almost equal. As long as the characteristics of the LED lamp beads are similar, the current of each LED is basically the same, and the brightness difference is small, which can achieve a better dimming effect. Figure 2 shown.

[0010] Since the series resistance R of the constant voltage light strip is much larger than the dynamic resistance r of the constant current light strip, it can be seen from the above two equations that under the condition of the same line loss at long distance and high brightness, the constant voltage light strip driven by the constant voltage power supply has better current consistency than the constant current light strip driven by the constant current power supply. However, due to the high brightness, the human eye is not sensitive to the difference. At low brightness, the line loss of the constant current light strip drops sharply, and the brightness difference of the constant current light strip driven by the constant current power supply is much better than that of the long distance constant voltage light strip driven by the constant voltage power supply.

[0011] Therefore, how to maintain the consistency of the brightness of the constant voltage light strip driven by the constant voltage dimming power supply under the condition of long distance and high brightness, and how to maintain the consistency of the brightness of the constant current light strip driven by the constant current dimming power supply under the condition of low brightness, becomes a problem that needs to be solved. Summary of the invention

[0012] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a constant voltage light strip driving device based on a constant current power supply with configurable output current.

[0013] The purpose of the present invention can be achieved by the following technical solutions:

[0014] A constant voltage light strip driving device based on a constant current power supply with configurable output current, comprising a constant current power supply, a driver and a light strip, wherein the constant current power supply is connected to the light strip through the driver, and the light strip is a constant voltage light strip or a constant current light strip;

[0015] The device combines a constant current dimming power supply with a constant voltage light strip to achieve good dimming effects at both high and low brightness levels.

[0016] Preferably, the driver is a configurable driver.

[0017] Preferably, the driver can be configured as a constant current driver or a constant voltage driver.

[0018] Preferably, the driver is provided with a voltage configuration circuit for the constant voltage light strip, which is used to configure the voltage function of the constant voltage lamp when the constant voltage light strip is selected to be driven.

[0019] Preferably, the driver is provided with a feedback voltage acquisition circuit and an output current regulation circuit, which are used to automatically adjust the maximum output current according to the feedback voltage when driving the constant voltage light strip, so that the output load voltage is always within a set error range with the set constant voltage light strip voltage.

[0020] Preferably, there are multiple constant voltage light strips with different lengths.

[0021] Preferably, the number of the drivers is the same as the number of the constant voltage light strips, and they correspond one to one.

[0022] Preferably, the constant current power supply can drive any one of the constant voltage type or constant current type light strips, or drive all constant voltage light strips within the load voltage range.

[0023] Preferably, when different constant current power supplies drive LED constant voltage light strips of different lengths, the constant current power supplies will automatically adjust the maximum output current according to the feedback output voltage.

[0024] Preferably, the constant voltage light strips include but are not limited to DC12V, 18V, 24V, 36V, 42V, 48V constant voltage light strips.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] 1) Under the condition of long distance and high brightness, it maintains the advantage of constant voltage dimming power supply driving constant voltage light strip with consistent brightness, while under the condition of low brightness, it also has the advantage of constant current dimming power supply driving constant current light strip with good brightness consistency.

[0027] 2) Make the constant current power supply drive both the constant current light strip and the constant voltage light strip.

[0028] 3) The constant current power supply can drive all constant voltage light strips within the load range, not only limited to DC12V, 24V, 36V, 48V, but also DC18V, 42V and other constant voltage light strips required by users.

[0029] 4) It saves users the time and labor cost of configuring the maximum output current of the constant current power supply according to the current required by the constant voltage light strips of different lengths.

[0030] 5) When the load is a long-distance constant-voltage light strip, dimming to low brightness will ensure that the brightness of each LED bead on the light strip is consistent. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the effect of a constant voltage power supply carrying a long-distance LED constant voltage lamp with low brightness;

[0032] Figure 2This is a schematic diagram of the effect of a constant current power supply carrying a long-distance LED constant current lamp with low brightness;

[0033] Figure 3 This is a schematic diagram of the effect of a constant current power supply carrying a long-distance LED constant voltage lamp with low brightness according to the present invention;

[0034] Figure 4 A schematic diagram showing that the maximum output current needs to be configured in advance when the constant current power supply of the present invention is loaded with LED constant voltage light strips of different lengths;

[0035] Figure 5 This is a schematic diagram of the constant current power supply of the present invention carrying LED constant voltage light strips of different lengths without the need to configure the maximum output current in advance. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0037] like Figure 3 As shown, a constant voltage light strip driving device based on a constant current power supply with configurable output current includes a constant current power supply, a driver and a light strip. The constant current power supply is connected to the light strip through the driver. The light strip is a constant voltage light strip or a constant current light strip. The device combines a constant current dimming power supply and a constant voltage light strip to achieve good dimming effects at high and low brightness.

[0038] The driver is a configurable driver. The driver can be configured as a constant current driver or a constant voltage driver. The driver is provided with a voltage configuration circuit for a constant voltage light strip, which is used to configure the voltage function of the constant voltage lamp when the constant voltage light strip is selected for driving.

[0039] The driver is provided with a feedback voltage acquisition circuit and an output current regulation circuit, which are used to automatically adjust the maximum output current according to the feedback voltage when driving the constant voltage light strip, so that the output load voltage is always within a set error range with the set constant voltage light strip voltage.

[0040] There are multiple constant voltage light strips with different lengths. The number of drivers is the same as that of constant voltage light strips, and they correspond one to one. The constant current power supply can drive any one of the constant voltage or constant current light strips, or drive all constant voltage light strips within the load voltage range. When different constant current power supplies drive LED constant voltage light strips of different lengths, the constant current power supply will automatically adjust the maximum output current according to the feedback output voltage. The constant voltage light strips include but are not limited to DC12V, 18V, 24V, 36V, 42V, 48V constant voltage light strips.

[0041] According to the above, there are two characteristics:

[0042] 1) At high brightness, the constant voltage power supply has good current consistency when driving long-distance light strips.

[0043] 2) At low brightness, the constant current power supply drives the long-distance light strip with good brightness consistency.

[0044] The present invention uses a constant current dimming power supply and a constant voltage light strip in combination to give full play to their respective advantages and obtain a good dimming effect at both high and low brightness. However, when using a constant current power supply to drive a constant voltage light strip, it is necessary to know in advance the current required for each light strip and configure the maximum output current of the corresponding constant current power supply according to the required current, such as Figure 4 So add the following to the constant current power supply:

[0045] 1) Configuration function for driving constant current or constant voltage light strips;

[0046] 2) Added the voltage function of configuring constant voltage lamps when choosing to drive constant voltage lamp strips;

[0047] 3) Add the function of automatically adjusting the maximum output current according to the feedback voltage when driving constant voltage light strips, so that the output load voltage is always within the ±0.2V error range with the set constant voltage light strip voltage;

[0048] 4) When the lamp strip voltage is tested in step 3, the current at that time can be recorded and used as a reference for dimming.

[0049] By adding the above functions to the constant current power supply, the constant current power supply can drive any type of constant voltage or constant current light strip, and can also drive all constant voltage light strips within the load voltage range. When different constant current power supplies drive LED constant voltage light strips of different lengths, there is no need to know in advance the specific current required for each LED constant voltage light strip. As long as it is within the output current range of the constant current power supply, the constant current power supply will automatically adjust the maximum output current according to the feedback output voltage, saving time and labor costs for measuring the current required for LED constant voltage light strips of different lengths and configuring different maximum output currents for the constant current power supply, such as Figure 5 shown.

[0050] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A constant voltage light strip driving device based on a constant current power supply with configurable output current, characterized in that: It includes a constant current power supply, a driver and a light strip, wherein the constant current power supply is connected to the light strip through the driver, and the light strip is a constant voltage light strip or a constant current light strip; The driver is provided with a feedback voltage acquisition circuit and an output current regulation circuit, which are used to automatically adjust the maximum output current according to the feedback voltage when driving the constant voltage light strip, so that the output load voltage is always within a set error range with the set constant voltage light strip voltage; When the voltage of the light strip is tested, record the current at that time and use it as a reference for dimming; When different constant current power supplies drive LED constant voltage light strips of different lengths, the constant current power supply will automatically adjust the maximum output current according to the feedback output voltage; The driver is provided with a voltage configuration circuit for the constant voltage light strip, which is used to configure the voltage of the constant voltage lamp when the constant voltage light strip is selected for driving.

2. A constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 1, characterized in that: The driver is a configurable driver.

3. A constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 2, characterized in that: The driver can be configured as a constant current driver or a constant voltage driver.

4. A constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 1, characterized in that: There are multiple constant voltage light strips with different lengths.

5. A constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 4, characterized in that: The number of the drivers is the same as that of the constant voltage light strips, and they correspond one to one.

6. The constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 1, characterized in that: The constant current power supply can drive any one of the constant voltage type or constant current type light strips, or drive all constant voltage light strips within the load voltage range.

7. A constant voltage light strip driving device based on a constant current power supply with configurable output current according to claim 1, characterized in that: The constant voltage light strips include DC12V, 18V, 24V, 36V, 42V, and 48V constant voltage light strips.

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