High-voltage flicker-free drive circuit

Abstract

A high voltage flicker-free driving circuit is provided. The lighting module includes a conversion module that converts an external power source into DC current, a low-voltage constant current module connected to the conversion module that converts the DC current into low-voltage current, and a flicker reduction module connected to the low-voltage constant current module that removes ripples from the low-voltage current to light the lighting module. The conversion chip DB1 and step-down chip U1 generate low-voltage DC current, which is then filtered by the filter chip IC1 and electrolytic capacitors CE1-CE5 to remove ripples in each frequency band, driving the lamp beads LED1-4 and LED137-140 to operate without flickering. The circuit design is simple, with a small number of components, which effectively reduces design and manufacturing costs and is suitable for small-sized and compact products.

Description

[Technical Field]

[0001] The present invention relates to the technical field of circuit design, and more particularly to a high-voltage flicker-free driving circuit. [Background technology]

[0002] LED lighting has a flickering phenomenon that can cause continuous damage to the human eye during use, so many LED lighting fixtures equipped with flicker-free circuit schemes have appeared on the market. However, most of the conventional flicker-free circuit schemes use two-stage topology circuits such as "PFC + Flyback / BUCK", which requires a large number of circuit components and a specially designed and assembled circuit module, resulting in relatively high design and manufacturing costs. Meanwhile, current market demand is focused on small, compact flicker-free lighting fixtures, and conventional flicker-free circuit schemes are unable to meet this market demand. Summary of the Invention [Means for solving the problem]

[0003] This invention discloses a high voltage flicker-free driving circuit. a conversion module that converts an external power source into direct current; a low-voltage constant current module connected to the conversion module for converting the DC current into a low-voltage current; and a flicker reduction module connected to the low-voltage constant current module to reduce ripples in the low-voltage current to light the lighting module.

[0004] In an alternative embodiment, the conversion module uses a conversion chip DB1, the second pin of the conversion chip DB1 is connected to the neutral line of the external power supply via a fuse resistor F1, the fourth pin is connected to the live line of the external power supply, the first pin is the positive pole of the DC current, the third pin is the negative pole of the DC current, and a varistor MVR1 is connected in parallel between the second pin and the fourth pin.

[0005] In an alternative embodiment, the low voltage constant current module comprises a step-down chip U1, a constant current resistor R1, a constant current resistor R2, and a constant current resistor R3; The step-down chip U1 converts the DC current into the low-voltage current; The constant current resistor R1, the constant current resistor R2 and the constant current resistor R3 are used to adjust the current value of the low voltage current.

[0006] In an alternative embodiment, the first pin of the converter chip DB1 is connected to the second pin of the step-down chip U1 through a resistor R4; The third pin of the converter chip DB1 is connected to the fifth pin of the step-down chip U1, connected to the sixth pin of the step-down chip U1 via the constant current resistor R3, connected to the seventh pin of the step-down chip U1 via the constant current resistor R2, and connected to the eighth pin of the step-down chip U1 via the constant current resistor R1.

[0007] In an alternative embodiment, the flicker elimination module includes a filter chip IC1 and electrolytic capacitors CE1, CE2, CE3, CE4, and CE5 connected in parallel.

[0008] In an alternative embodiment, the first pin of the step-down chip U1 transmits the low-voltage current to the first and third pins of the filter chip IC1; The second pin of the step-down chip U1 is connected to the lighting module, and the flicker reduction module is connected in parallel with the lighting module.

[0009] In an alternative embodiment, the lighting module includes a first lighting unit configured by connecting the lamp bead LED1 and the lamp bead LED137 in series, a second lighting unit configured by connecting the lamp bead LED2 and the lamp bead LED138 in series, a third lighting unit configured by connecting the lamp bead LED3 and the lamp bead LED139 in series, and a fourth lighting unit configured by connecting the lamp bead LED4 and the lamp bead LED140 in series; The first lighting unit, the second lighting unit, the third lighting unit and the fourth lighting unit are connected in parallel.

[0010] In an alternative embodiment, a bypass low-voltage constant current module is connected in parallel to the low-voltage constant current module, which synchronously receives the DC current output from the conversion module and synchronously outputs the low-voltage current; a bypass flicker elimination module is provided in parallel with the flicker elimination module, and the bypass flicker elimination module receives the low-voltage current synchronously output from the low-voltage constant-current module and the bypass low-voltage constant-current module; The de-flicker module and the bypass de-flicker module synchronously supply power to the lighting module.

[0011] In an alternative embodiment, a bypass conversion module is connected to an external power source in synchronization with the conversion module, transmits bypass DC current to the bypass low-voltage constant current module, the bypass low-voltage constant current module transmits bypass low-voltage current to the bypass flicker elimination module, and the bypass flicker elimination module supplies power to the bypass lighting module. [Effects of the Invention]

[0012] Compared with the prior art, the present invention has the following advantageous effects: The converter chip and step-down chip generate low-voltage DC current, and then the filter chip and electrolytic capacitor eliminate ripples in each frequency band, driving the lamp beads to operate without flickering. The circuit design is simple, the number of components is small, and the design and manufacturing costs are effectively reduced, making it suitable for small-sized and compact products.

[0013] In order to clearly explain the technical means in the present embodiment, the accompanying drawings that need to be used to depict the embodiments will be briefly described below. The accompanying drawings depicted below only represent some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these accompanying drawings without any creative effort. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a circuit principle diagram of a high-voltage flicker-free drive circuit according to an embodiment of the present invention. [Figure 2] 1 is a circuit principle diagram of a high-voltage flicker-free driving circuit in which a bypass low-voltage constant current module and a bypass flicker elimination module are added in cascade connection according to the present embodiment. [Figure 3] FIG. 1 is a circuit diagram of a multi-channel cascaded high-voltage flicker-free drive circuit according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] The technical means in the embodiments of the present invention will be described in detail below with reference to the drawings, but it goes without saying that the described embodiments are only some of the embodiments of the present invention and do not represent all of the embodiments. Any other embodiments that can be obtained by those skilled in the art based on the embodiments of the present invention without any creative effort fall within the scope of protection of the present invention.

[0016] Referring to FIGS. 1 to 3, the high-voltage flicker-free driving circuit according to this embodiment includes: a conversion module that converts an external power source into direct current; a low-voltage constant current module connected to the conversion module to convert direct current into low-voltage current; and a flicker elimination module connected to the low-voltage constant current module to eliminate ripples in the low-voltage current to light the lighting module.

[0017] In this embodiment, AC / DC conversion and voltage step-down are achieved using only a conversion chip and a step-down chip, and then a filter chip and an electrolytic capacitor are used to remove ripples in each frequency band, driving the lamp beads to operate without flickering.

[0018] Compared with the two-stage topology circuit scheme of "PFC + Flyback / BUCK", the circuit design of this embodiment is simpler and has fewer components, and does not require special design and assembly of additional circuit modules. By improving the traditional circuit scheme, it effectively reduces design and manufacturing costs and is suitable for small-sized and compact products.

[0019] In an alternative embodiment, the conversion module uses a conversion chip DB1, the second pin of which is connected to the neutral line of the external power supply via a fuse resistor F1, the fourth pin of which is connected to the live line of the external power supply, the first pin of which is the positive pole of the DC current, the third pin of which is the negative pole of the DC current, and a varistor MVR1 is connected in parallel between the second pin and the fourth pin.

[0020] Here, there is no need to provide a separate power supply drive conversion device for the external power supply, and AC-DC conversion is achieved using only a lightweight conversion chip and fuse element.

[0021] As an alternative embodiment, the low voltage constant current module includes a step-down chip U1, a constant current resistor R1, a constant current resistor R2, and a constant current resistor R3; The step-down chip U1 converts the DC current into a low-voltage current, The constant current resistor R1, the constant current resistor R2 and the constant current resistor R3 are used to adjust the current value of the low voltage current.

[0022] Here, by adjusting the number, resistance value and assembly node of each constant current resistor, the DC current can be modulated to a low voltage current suitable for the lighting unit, and the step-down adjustment mechanism is simple and easy to implement, making it suitable for small products.

[0023] In an alternative embodiment, the first pin of the converter chip DB1 is connected to the second pin of the step-down chip U1 through a resistor R4; The third pin of the converter chip DB1 is connected to the fifth pin of the step-down chip U1, connected to the sixth pin of the step-down chip U1 via a constant current resistor R3, connected to the seventh pin of the step-down chip U1 via a constant current resistor R2, and connected to the eighth pin of the step-down chip U1 via a constant current resistor R1.

[0024] In an alternative embodiment, the flicker elimination module includes a filter chip IC1 and electrolytic capacitors CE1, CE2, CE3, CE4, and CE5 connected in parallel; The filter chip IC1 is used to remove low-frequency ripple. Electrolytic capacitor CE1, electrolytic capacitor CE2, electrolytic capacitor CE3, electrolytic capacitor CE4, and electrolytic capacitor CE5 are connected in parallel and are used to remove high frequency ripples.

[0025] In an alternative embodiment, pin 1 of the step-down chip U1 transmits a low voltage current to pins 1 and 3 of the filter chip IC1; The second pin of the step-down chip U1 is connected to the lighting module, and the flicker reduction module is connected in parallel with the lighting module.

[0026] Here, the filter chip removes the low-frequency ripple of 100Hz / 120Hz generated in the previous circuit, and the parallel connection of electrolytic capacitors CE1, CE2, CE3, CE4, and CE5 removes the high-frequency ripple, thereby removing a wide range of ripple and achieving flicker-free driving output.

[0027] In an alternative embodiment, the lighting module includes a first lighting unit configured by connecting the lamp bead LED1 and the lamp bead LED137 in series, a second lighting unit configured by connecting the lamp bead LED2 and the lamp bead LED138 in series, a third lighting unit configured by connecting the lamp bead LED3 and the lamp bead LED139 in series, and a fourth lighting unit configured by connecting the lamp bead LED4 and the lamp bead LED140 in series; The first lighting unit, the second lighting unit, the third lighting unit and the fourth lighting unit are connected in parallel.

[0028] In an alternative embodiment, a bypass low-voltage constant current module is installed in parallel with the low-voltage constant current module, which synchronously receives the DC current output from the conversion module and synchronously outputs the low-voltage current; A bypass flicker elimination module is installed in parallel with the flicker elimination module, and the bypass flicker elimination module receives the low-voltage current synchronously output from the low-voltage constant current module and the bypass low-voltage constant current module; The anti-flicker module and the bypass anti-flicker module synchronously power the lighting module.

[0029] Here, by adding a bypass low-voltage constant current module and a bypass flicker elimination module in cascade connection, the current value of the output low-voltage current increases, thereby achieving the purpose of increasing the overall power of the lamp.

[0030] In an alternative embodiment, the bypass conversion module is connected to an external power source in synchronization with the conversion module, and transmits bypass DC current to the bypass low-voltage constant current module, which transmits bypass low-voltage current to the bypass flicker elimination module, and the bypass flicker elimination module supplies power to the bypass lighting module.

[0031] In addition, when a bypass lighting module is added, an independent bypass conversion module, a bypass low-voltage constant current module, and a bypass flicker elimination module are configured corresponding to the bypass lighting module, and an independent bypass circuit is formed, and the bypass circuit is connected to the same external power source.

[0032] Compared with the prior art, this embodiment has the following advantageous effects: The converter chip and step-down chip generate low-voltage DC current, and then the filter chip and electrolytic capacitor eliminate ripples in each frequency band, driving the lamp beads to operate without flickering. The circuit design is simple, the number of components is small, and the design and manufacturing costs are effectively reduced, making it suitable for small-sized and compact products.

Claims

1. A high voltage flicker-free drive circuit, comprising: a conversion module that converts an external power source into direct current; a low-voltage constant current module connected to the conversion module for converting the DC current into a low-voltage current; a flicker reduction module connected to the low-voltage constant current module, for reducing ripples in the low-voltage current to light the lighting module; A high-voltage flicker-free driving circuit comprising:

2. 2. The high-voltage flicker-free driving circuit according to claim 1, wherein the conversion module uses a conversion chip DB1, the second pin of the conversion chip DB1 is connected to the neutral line of the external power supply through a fuse resistor F1, the fourth pin is connected to the live line of the external power supply, the first pin is the positive pole of the DC current, the third pin is the negative pole of the DC current, and a varistor MVR1 is connected in parallel between the second pin and the fourth pin.

3. The low voltage constant current module includes a step-down chip U1, a constant current resistor R1, a constant current resistor R2, and a constant current resistor R3; The step-down chip U1 converts the DC current into the low-voltage current; The constant current resistors R1, R2 and R3 are used to adjust the current value of the low voltage current.

3. The high voltage flicker-free driving circuit according to claim 2.

4. The first pin of the converter chip DB1 is connected to the second pin of the step-down chip U1 through a resistor R4; The third pin of the converter chip DB1 is connected to the fifth pin of the step-down chip U1, to the sixth pin of the step-down chip U1 via the constant current resistor R3, to the seventh pin of the step-down chip U1 via the constant current resistor R2, and to the eighth pin of the step-down chip U1 via the constant current resistor R1.

4. The high voltage flicker-free driving circuit according to claim 3.

5. 4. The high-voltage flicker-free driving circuit of claim 3, wherein the flicker elimination module comprises a filter chip IC1 and electrolytic capacitors CE1, CE2, CE3, CE4, and CE5 connected in parallel.

6. The first pin of the step-down chip U1 transmits the low-voltage current to the first and third pins of the filter chip IC1; The second pin of the step-down chip U1 is connected to the lighting module, and the flicker reduction module is connected in parallel with the lighting module.

6. The high voltage flicker-free driving circuit according to claim 5.

7. The lighting module includes a first lighting unit configured by connecting a lamp bead LED1 and a lamp bead LED137 in series, a second lighting unit configured by connecting a lamp bead LED2 and a lamp bead LED138 in series, a third lighting unit configured by connecting a lamp bead LED3 and a lamp bead LED139 in series, and a fourth lighting unit configured by connecting a lamp bead LED4 and a lamp bead LED140 in series; The first lighting unit, the second lighting unit, the third lighting unit, and the fourth lighting unit are connected in parallel.

2. The high voltage flicker-free driving circuit according to claim 1.

8. a bypass low-voltage constant current module is provided in parallel with the low-voltage constant current module, which receives the DC current output from the conversion module in synchronization with the low-voltage constant current module and outputs the low-voltage constant current in synchronization with the low-voltage constant current module; a bypass flicker elimination module is provided in parallel with the flicker elimination module, and the bypass flicker elimination module receives the low-voltage current synchronously output from the low-voltage constant-current module and the bypass low-voltage constant-current module; The de-flicker module and the bypass de-flicker module supply power to the lighting module in synchronization.

2. The high voltage flicker-free driving circuit according to claim 1.

9. 9. The high-voltage flicker-free driving circuit of claim 8, wherein the bypass conversion module is connected to an external power supply in synchronization with the conversion module, transmits bypass DC current to the bypass low-voltage constant current module, the bypass low-voltage constant current module transmits bypass low-voltage current to the bypass flicker elimination module, and the bypass flicker elimination module supplies power to the bypass lighting module.

Images