High-voltage LED driving method, high-voltage constant-current constant-power chip and high-voltage LED driving circuit

Abstract

The application discloses a high-voltage LED driving method, a high-voltage constant-current constant-power chip and a high-voltage LED driving circuit. The high-voltage LED driving method comprises the following steps: providing an LED module, wherein the LED module comprises x light-emitting units which are sequentially electrically connected in a circuit loop; under the condition of three-phase full-wave rectification power supply, the current values of constant current sources are set to meet the total power P of the LED module LED Constant condition: Is I =P LED / (Vf1+Vf2+...+Vf I ), wherein Is I is the current value of the Ith constant current source, Vf1, Vf2,..., Vf I are normal working voltages of the 1st working circuit, the 2nd working circuit,..., the Ith working circuit respectively, and 1<=I<=N. The application adopts a three-phase high-voltage linear driving LED lamp bead, which not only inherits the advantages of a linear driving circuit, such as compact structure, small size and low cost, but also avoids the problems of a switching driving circuit, such as complex structure and easy failure.

Description

Technical Field

[0001] This invention relates to a high-voltage LED driving method, a high-voltage constant current and constant power chip, and a high-voltage LED driving circuit, belonging to the field of semiconductor lighting and display technology. Background Technology

[0002] High-voltage linearly driven LED light source boards have the advantages of being simple to use and inexpensive, and have been widely used. To improve driving efficiency, multi-segment driving is often adopted, such as... Figure 1 As shown. Alternating current, after rectification, forms a pulsating voltage (Vin). When Vf1 + Vf2 ≥ V... in When Vf1 ≥ Vf1, current source I s1 When activated, the first LED bead lights up when Vf1 + Vf2 + Vf3 ≥ V in When Vf1 + Vf2 ≥ Vf1, the current source I s1 Shutdown, current source I s2 When activated, the first and second LED segments light up, and so on. When Vin ≥ Vf1 + ... + VfN, I... s1 To I sN-1 Close, I sN When powered on, all LEDs illuminate. Typically, to achieve a high power factor (PF), the current I of each sub-current source in a high-voltage linear constant current IC is... s1 ≤ I s2 ≤ I s3 ≤…≤ I sn As can be seen, the total brightness of the LED light source changes with the input voltage, which causes flickering and instability in total brightness, affecting the practical application effect.

[0003] Linear LED driver circuits mostly use single-phase AC power, but the high voltage ripple after full-bridge rectification of single-phase AC power prevents it from simultaneously achieving high power factor (PF) and low flicker. Low driving efficiency and unstable light source brightness limit the application of linear LED drivers in the high-end market. For three-phase AC power, the input current of existing switching LED lighting driver circuits is excessively distorted due to the influence of nonlinear loads, which can easily damage circuit equipment and pollute the power grid. Switching LED driver circuits generally incorporate PFC power factor correction, and their circuits contain high-frequency transformers, inductors, large capacitors, switching transistors, and other power devices, resulting in complex circuit structures and high costs. Furthermore, the short lifespan of energy storage components such as electrolytic capacitors and inductors in such circuits can lead to circuit failure, preventing the full utilization of the advantages of LEDs. Summary of the Invention

[0004] The main objective of this invention is to provide a high-voltage LED driving method, a high-voltage constant current and constant power chip, and a high-voltage LED driving circuit, thereby overcoming the shortcomings of the prior art.

[0005] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0006] This invention provides a high-voltage LED driving method, comprising:

[0007] An LED module is provided, comprising x light-emitting units sequentially electrically connected in a circuit loop. The first to i-th light-emitting units are connected to a first working circuit segment. One terminal of the first working circuit segment is electrically connected to one terminal of the circuit loop, and the other terminal of the first working circuit segment is electrically connected to the other terminal of the circuit loop via a first constant current source. The (i+1)-th to k-th light-emitting units are connected to a second working circuit segment. One terminal of the second working circuit segment is electrically connected to the other terminal of the first working circuit segment. The other pole of the segment working circuit is electrically connected to the other pole of the circuit loop via the second constant current source, and so on. The m to x light-emitting units are connected to the Nth segment working circuit. One pole of the Nth segment working circuit is electrically connected to the other pole of the (N-1)th segment working circuit. The other pole of the Nth segment working circuit is electrically connected to the other pole of the circuit loop via the Nth constant current source. The two poles of the circuit loop are respectively used to connect to the positive and negative poles of the power supply. Where x and N are integers greater than or equal to 2, and i, k, and m are integers greater than or equal to 1.

[0008] Under three-phase full-wave rectification power supply conditions, the current values ​​of each constant current source are set to meet the total power P of the LED module. LED The condition for constancy:

[0009] Is I =P LED / (Vf1 + Vf2 +…+ Vf I )

[0010] Among them, Is I These are the current values ​​of the first constant current source, Vf1, Vf2, ... Vf I These are the normal operating voltages of the first working circuit, the second working circuit, ..., the first working circuit, where 1 ≤ I ≤ N.

[0011] In another aspect, the present invention provides a high-voltage constant current and constant power chip, which includes a constant power control module, a voltage comparison module, a bandgap reference voltage generation module, an error amplifier module, a logic control module, a power supply voltage regulation module, and N switching modules. The chip also has a voltage sampling port, N constant current output ports, and N output current value setting ports.

[0012] One end of the constant power control module is connected to the voltage sampling port, and the other end is connected in sequence to the voltage comparison module, the error amplifier module, and the logic control module.

[0013] The control terminals of the first to Nth switch modules are all connected to the logic control module, the input terminals are connected to the first to Nth output current value setting ports respectively, and the output terminals are connected to the first to Nth constant current output ports respectively.

[0014] The voltage comparison module is also connected to the input terminals of the bandgap reference voltage generation module and the Nth switch module, respectively.

[0015] In another aspect, the present invention provides a high-voltage LED driving circuit, including an LED module. The LED module includes x light-emitting units that are sequentially electrically connected in the driving circuit. The first to the i-th light-emitting units are connected to the first working circuit, the (i+1)-th to the k-th light-emitting units are connected to the second working circuit, and so on. The m-th to the x-th light-emitting units are connected to the N-th working circuit. The two poles of the driving circuit are respectively used to be electrically connected to the positive and negative poles of the power supply. Here, x and N are integers greater than or equal to 2, and i, k, and m are integers greater than or equal to 1.

[0016] The driving circuit also includes the high-voltage constant current constant power chip.

[0017] Specifically, one pole of the first working circuit is electrically connected to one pole of the driving circuit, and the other pole is connected to the first constant current output port of the high-voltage constant current constant power chip. One pole of the second working circuit is electrically connected to the other pole of the first working circuit, and the other pole of the second working circuit is connected to the second constant current output port of the high-voltage constant current constant power chip. Similarly, one pole of the Nth working circuit is electrically connected to the other pole of the (N-1)th working circuit, and the other pole of the Nth working circuit is connected to the Nth constant current output port of the high-voltage constant current constant power chip.

[0018] The high-voltage constant current and constant power chip also has N internal reference voltage ports, each of which is electrically connected to the other pole of the drive circuit via an external control resistor.

[0019] Compared with the prior art, the advantages of the present invention include:

[0020] 1) The high-voltage LED driving circuit and driving method provided by the present invention, which is composed of a three-phase AC power supply and a high-voltage constant current constant power IC, can effectively solve the problem of instability caused by the change of total LED brightness with input voltage.

[0021] 2) The high-voltage linear control method for reducing flicker and maintaining constant brightness provided in this embodiment of the invention offers flexible control over the LED current in each segment, has a wide range of applications, and can flexibly adjust the external control resistor Rref according to the set Vf for each segment. i Achieve constant power and eliminate flicker. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a linear multi-segment LED driver circuit in the prior art;

[0023] Figure 2 This is a schematic diagram of a three-phase (high voltage) linear multi-segment LED driving circuit provided in a typical embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the working principle of a high-voltage constant current and constant power IC provided in a typical embodiment of the present invention;

[0025] Figure 4 yes Figure 3 The local structure and schematic diagram at point A in the middle structure;

[0026] Figure 5 The curve of the duty cycle of Is2 conduction in a high-voltage linear dual-segment LED driver as a function of line voltage is shown in an embodiment of the present invention.

[0027] Figure 6 The curve of power factor versus line voltage for high-voltage linear dual-segment LED driver in an embodiment of the present invention is shown.

[0028] Figure 7 The curves showing the total harmonic distortion (@380V±10% line voltage) of the high-voltage linear dual-segment LED driver in an embodiment of the present invention as a function of line voltage are shown. Detailed Implementation

[0029] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. The following will further explain and illustrate this technical solution, its implementation process, and its principles.

[0030] The present invention provides a high-voltage LED driving circuit and driving method, which adopts a three-phase high-voltage linear driving LED lamp bead scheme. It inherits the advantages of linear driving circuits, such as compact structure, small size and low cost, while avoiding the problems of complex circuit structure and easy failure of switch-type driving.

[0031] This invention provides a high-voltage LED driving method, comprising:

[0032] An LED module is provided, comprising x light-emitting units sequentially electrically connected in a circuit loop. The first to i-th light-emitting units are connected to a first working circuit segment. One terminal of the first working circuit segment is electrically connected to one terminal of the circuit loop, and the other terminal of the first working circuit segment is electrically connected to the other terminal of the circuit loop via a first constant current source. The (i+1)-th to k-th light-emitting units are connected to a second working circuit segment. One terminal of the second working circuit segment is electrically connected to the other terminal of the first working circuit segment. The other pole of the segment working circuit is electrically connected to the other pole of the circuit loop via the second constant current source, and so on. The m to x light-emitting units are connected to the Nth segment working circuit. One pole of the Nth segment working circuit is electrically connected to the other pole of the (N-1)th segment working circuit. The other pole of the Nth segment working circuit is electrically connected to the other pole of the circuit loop via the Nth constant current source. The two poles of the circuit loop are respectively used to connect to the positive and negative poles of the power supply. Where x and N are integers greater than or equal to 2, and i, k, and m are integers greater than or equal to 1.

[0033] Under three-phase full-wave rectification power supply conditions, the current values ​​of each constant current source are set to meet the total power P of the LED module. LED The condition for constancy:

[0034] Is I =P LED / (Vf1 + Vf2 +…+ Vf I )

[0035] Among them, Is I These are the current values ​​of the first constant current source, Vf1, Vf2, ... Vf I These are the normal operating voltages of the first working circuit, the second working circuit, ..., the first working circuit, where 1 ≤ I ≤ N.

[0036] In one embodiment, Is I It varies with the input voltage; the higher the input voltage, the more light-emitting units are active.

[0037] In one embodiment, Vf1 is less than or equal to the voltage of the power supply, that is, Vf1 is less than or equal to the minimum value of the voltage of the power supply.

[0038] In one embodiment, the LED module includes a high-voltage linearly driven LED module.

[0039] In one embodiment, the light-emitting unit includes an LED chip or an LED bead.

[0040] In one embodiment, one pole of the circuit loop is positive, and the other pole is negative or grounded.

[0041] In another aspect, the present invention provides a high-voltage constant current and constant power chip, which includes a constant power control module, a voltage comparison module, a bandgap reference voltage generation module, an error amplifier module, a logic control module, a power supply voltage regulation module, and N switching modules. The chip also has a voltage sampling port, N constant current output ports, and N output current value setting ports.

[0042] One end of the constant power control module is connected to the voltage sampling port, and the other end is connected in sequence to the voltage comparison module, the error amplifier module, and the logic control module.

[0043] The control terminals of the first to Nth switch modules are all connected to the logic control module, the input terminals are connected to the first to Nth output current value setting ports respectively, and the output terminals are connected to the first to Nth constant current output ports respectively.

[0044] The voltage comparison module is also connected to the input terminals of the bandgap reference voltage generation module and the Nth switch module, respectively.

[0045] For example, the output terminal of any of the first to Nth switching modules can be connected to the power supply voltage regulation module.

[0046] In one embodiment, the constant power control module may include multiple constant power control sub-modules arranged in parallel.

[0047] In one embodiment, the voltage comparison module may include multiple voltage comparison sub-modules arranged in parallel.

[0048] In one embodiment, the high-voltage constant current constant power chip may further include a low-voltage gating module, one end of which is connected to a voltage sampling port and the other end of which is connected to a voltage comparison module.

[0049] Specifically, the high-voltage constant current and constant power chip also includes an over-temperature protection and under-voltage lockout module, which is connected to the bandgap reference voltage generation module.

[0050] In another aspect, the present invention provides a high-voltage LED driving circuit, including an LED module. The LED module includes x light-emitting units that are sequentially electrically connected in the driving circuit. The first to the i-th light-emitting units are connected to the first working circuit, the (i+1)-th to the k-th light-emitting units are connected to the second working circuit, and so on. The m-th to the x-th light-emitting units are connected to the N-th working circuit. The two poles of the driving circuit are respectively used to be electrically connected to the positive and negative poles of the power supply. Here, x and N are integers greater than or equal to 2, and i, k, and m are integers greater than or equal to 1.

[0051] The driving circuit also includes the high-voltage constant current constant power chip.

[0052] Specifically, one pole of the first working circuit is electrically connected to one pole of the driving circuit, and the other pole is connected to the first constant current output port of the high-voltage constant current constant power chip. One pole of the second working circuit is electrically connected to the other pole of the first working circuit, and the other pole of the second working circuit is connected to the second constant current output port of the high-voltage constant current constant power chip. Similarly, one pole of the Nth working circuit is electrically connected to the other pole of the (N-1)th working circuit, and the other pole of the Nth working circuit is connected to the Nth constant current output port of the high-voltage constant current constant power chip.

[0053] The high-voltage constant current and constant power chip also has N internal reference voltage ports, each of which is electrically connected to the other pole of the drive circuit via an external control resistor.

[0054] Specifically, the power supply is a three-phase full-wave rectified power supply.

[0055] Specifically, the switching module includes a MOSFET.

[0056] The following will further explain the technical solution, its implementation process, and principles in conjunction with the accompanying drawings and specific implementation examples. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Furthermore, unless otherwise expressly specified and limited, the terms "connected" and "linked" used in the embodiments of the present invention should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal connection of two components; it can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0057] Example

[0058] Please see Figure 2 and Figure 3A three-phase (high voltage) linear multi-segment LED driving circuit includes an LED module. The LED module includes x light-emitting units that are sequentially connected in the driving circuit. The first to the i-th light-emitting units are connected to the first segment of the working circuit, the (i+1)-th to the k-th light-emitting units are connected to the second segment of the working circuit, and so on. The m-th to the x-th light-emitting units are connected to the N-th segment of the working circuit. The two poles of the driving circuit are respectively used to connect to the positive and negative poles of the power supply. Here, x and N are integers greater than or equal to 2, and i, k, and m are integers greater than or equal to 1.

[0059] In this embodiment, please refer to the following: Figure 4 In the diagram, pin OUT is the constant current output port, pin VT is the voltage sampling port, and pin REXT is the output current value setting port. The driving circuit also includes a high-voltage constant current and constant power chip. The high-voltage constant current and constant power chip includes a constant power control module, a voltage comparison module, a bandgap reference voltage generation module, an error amplifier module, a logic control module, a power supply voltage regulation module, and N switching modules. The chip also has a voltage sampling port, N constant current output ports, and N output current value setting ports.

[0060] In this embodiment, one end of the constant power control module is connected to the voltage sampling port, and the other end is sequentially connected to the voltage comparison module, the error amplifier module, and the logic control module; the control terminals of the 1st to Nth switching modules are all connected to the logic control module, the input terminals are respectively connected to the 1st to Nth output current value setting ports, and the output terminals are respectively connected to the 1st to Nth constant current output ports; the voltage comparison module is also connected to the input terminals of the bandgap reference voltage generation module and the Nth switching module.

[0061] For example, the output terminal of any of the first to Nth switching modules can be connected to the power supply voltage regulation module.

[0062] In this embodiment, the constant power control module includes multiple constant power control sub-modules arranged in parallel, and the voltage comparison module includes multiple voltage comparison sub-modules arranged in parallel.

[0063] In this embodiment, the high-voltage constant current and constant power chip further includes an over-temperature protection and undervoltage lockout module, which is connected to the bandgap reference voltage generation module.

[0064] Please continue reading. Figure 4In this embodiment, more preferably, a low-voltage selection module can be added to the high-voltage constant current constant power chip. One end of the module is connected to the voltage sampling port, and the other end is connected to the voltage comparison module. This module is used to compare the external input reference voltage Vorext with the built-in reference voltage and select one of the low-voltage paths to the voltage comparison module for comparison with the source voltage of MOSn. This controls the output current, enabling the nth output current to be continuously adjustable within the range of 0 to Vinrext / Rrefn, thereby adjusting the brightness of the LED light source.

[0065] In this embodiment, one pole of the first working circuit is electrically connected to one pole of the driving circuit, and the other pole is connected to the first constant current output port of the high-voltage constant current constant power chip. One pole of the second working circuit is electrically connected to the other pole of the first working circuit, and the other pole of the second working circuit is connected to the second constant current output port of the high-voltage constant current constant power chip. Similarly, one pole of the Nth working circuit is electrically connected to the other pole of the (N-1)th working circuit, and the other pole of the Nth working circuit is connected to the Nth constant current output port of the high-voltage constant current constant power chip. The high-voltage constant current constant power chip also has N internal reference voltage ports, and each internal reference voltage port is electrically connected to the other pole of the driving circuit via an external control resistor.

[0066] In this embodiment, the power supply is a three-phase full-wave rectified power supply, etc., and the switching module includes MOSFETs, etc., wherein the MOSFETs are used as switching devices, and the current control unit in the driving circuit controls the switching state of the MOSFETs, thereby controlling the current of the LED string within the expected range to ensure that the total output power of the LED string is constant.

[0067] Please refer to it again. Figure 2 , Figure 2 This is a schematic diagram of a three-phase (high-voltage) linear multi-segment LED driver circuit. A high-voltage linear control method for reducing flicker and maintaining constant brightness includes:

[0068] Under three-phase full-wave rectification power supply conditions, the current values ​​of each sub-current source in the constant current IC are set to meet the condition of constant total power of the LED light source:

[0069] Is1 * Vf1 = Is2 * (Vf1 + Vf2) = Is3 * (Vf1 + Vf2 + Vf3) = Isn * (Vf1 +Vf2 +…+ Vf n ) = P LED

[0070] That is: Is i = P LED / (Vf1 + Vf2 +…+ Vfi )

[0071] As the LED string is lit sequentially, the current decreases proportionally with the increase in the number of lit segments. Regardless of changes in the input voltage, the total power P of the LED light source remains constant. LED Both can remain constant, thus solving the flicker problem and the instability of the total LED brightness caused by changes in input voltage.

[0072] Specifically, under single-phase full-bridge rectified power supply conditions, this method cannot eliminate flicker without adding a parallel capacitor because the minimum voltage of the rectified half-wave waveform is 0V, which will inevitably create a time gap when the light is off. If a parallel capacitor is added, the power factor (PF) value will be greatly affected. However, under three-phase full-wave rectified power supply conditions, according to the minimum voltage of the power grid standard of 420V, as long as the first segment Vf ≤ 420V, there will be no time gap when the light is off. Thus, flicker can be eliminated while maintaining constant power, and the impact on PF and THD is very small, making it suitable for mid-to-high-end applications.

[0073] In this embodiment, each OUT i terminal of the high-voltage constant current constant power IC is internally connected to a constant current source Is. i Its current is determined by the internal reference voltage Vref i and external control resistor Rref i Decision, that is: Is i = Vref i / Rref i As the input voltage increases, the lights are illuminated segment by segment according to the high-voltage linear control method described above.

[0074] In this embodiment, the total LED power P is maintained. LED Since it is constant, we can obtain: Rref i = Vref i x (Vf1+ Vf2 +…+ Vf i ) / P LED According to the domestic three-phase AC power grid standard, the minimum voltage is 380V-10% of the line voltage, so the preferred Vf1 is 420V + / - 20V.

[0075] In this embodiment, when constant power is used, the power factor (PF) and total harmonic distortion (THD) fluctuate only slightly.

[0076]

[0077]

[0078] Where T is the period of the sinusoidal voltage, and I nLet α be the amplitude of each harmonic. n This represents the phase difference between each harmonic and the fundamental frequency.

[0079] Specifically, when the total power P LED Under constant conditions, as the number of lit segments (i.e., the number of light-emitting units or working circuits) increases, the current flowing through the LED string gradually decreases, i.e., PF↓ and THD↑, but the values ​​of both fluctuate only slightly. Taking a high-voltage linear dual-segment LED driver as an example, under a line voltage of 380V±10%, assuming the first segment Vf1 = 420V and the second segment Vf2+Vf1 = 495V, in order to maintain P... LED For constant voltage, Is1 and Is2 must satisfy the following condition: Is2 / Is1 = Vf1 / (Vf1 + Vf2) = 0.85. The duty cycle of Is2 in a high-voltage linear dual-segment LED driver (i.e., the ratio of Is2's conduction time to the total conduction time of Is1 and Is2) as a function of line voltage is shown in the curve below. Figure 5 As shown. By Figure 5 It can be seen that as the line voltage increases, the duty cycle of Is2 gradually increases and then tends to stabilize. The curve of power factor (PF) versus line voltage is shown below. Figure 6 As shown, the curve of total harmonic distortion (THD) as a function of line voltage is as follows: Figure 7 As shown, by Figure 6 , Figure 7 It can be seen that the values ​​of PF and THD do not fluctuate much with the fluctuation of circuit voltage.

[0080] This invention employs a three-phase AC power supply and a high-voltage constant current / constant power IC chip for linear LED driving. This solves the problems of LED brightness instability caused by changes in input voltage and LED flicker, resulting in superior LED driving performance. Furthermore, the high-voltage constant current / constant power IC chip in this invention features a unique internal current and resistance design that meets the requirements of Is... i = P LED / (Vf1+ Vf2 +…+ Vf i That is, as the number of lit segments increases, the current decreases proportionally. Furthermore, three-phase AC power, with its unique advantages, can compensate for the shortcomings of using single-phase AC power as the linear drive power supply for LEDs in many ways.

[0081] This invention provides a high-voltage LED driving circuit and driving method. The voltage frequency of three-phase electricity after full-bridge rectification is three times that of single-phase electricity after rectification. Furthermore, the DC component of the three-phase rectified voltage is large, accounting for approximately 90.7% of the effective voltage. Its higher frequency and significant DC component can effectively alleviate the flicker problem. In addition, the voltage after three-phase rectification is much higher than that after single-phase rectification, which reduces the current under the same power, thereby reducing the cable diameter and resulting in lower wiring costs.

[0082] This invention uses three-phase high-voltage linear drive LED beads, which not only inherits the advantages of linear drive circuits such as compact structure, small size and low cost, but also avoids the problems of complex structure and easy failure of switching drive circuits.

[0083] The present invention provides a high-voltage LED driving circuit and driving method. The high-reliability driving circuit, composed of a three-phase AC power supply and a high-voltage constant current and constant power IC, can effectively solve the problem of instability caused by changes in the total brightness of the LED as the input voltage changes.

[0084] The high-voltage linear control method for reducing flicker and maintaining constant brightness provided in this embodiment of the invention offers flexible control over the LED current in each segment, has a wide range of applications, and allows for flexible adjustment of the external control resistor Rref according to the set Vf for each segment. i Achieve constant power and eliminate flicker.

[0085] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A high-voltage LED driving method, characterized in that... include: An LED module is provided, comprising x light-emitting units sequentially electrically connected in a circuit loop. The first to i-th light-emitting units are connected to a first working circuit segment. One terminal of the first working circuit segment is electrically connected to one terminal of the circuit loop, and the other terminal of the first working circuit segment is electrically connected to the other terminal of the circuit loop via a first constant current source. The (i+1)-th to k-th light-emitting units are connected to a second working circuit segment. One terminal of the second working circuit segment is electrically connected to the other terminal of the first working circuit segment. The other pole is electrically connected to the other pole of the circuit loop via the second constant current source, and so on. The m to x light-emitting units are connected to the Nth working circuit. One pole of the Nth working circuit is electrically connected to the other pole of the (N-1)th working circuit. The other pole of the Nth working circuit is electrically connected to the other pole of the circuit loop via the Nth constant current source. The two poles of the circuit loop are respectively used to connect to the positive and negative poles of the power supply. Where x and N are integers greater than 2, and i, k, and m are integers greater than or equal to 1. The power supply is a three-phase full-wave rectified power supply. Under the condition of three-phase full-wave rectification power supply, by adjusting N external control resistors corresponding to each constant current source, the current value of each constant current source is set to meet the total power P of the LED module LED Constant conditions: Is I =P LED / (Vf1 + Vf2 +…+ Vf I ) ; Among them, Is I These are the current values ​​of the first constant current source, Vf1, Vf2, ... Vf I These are the normal operating voltages of the first working circuit, the second working circuit, ..., the first working circuit, 1≤I≤N, and the normal operating voltage Vf1 of the first working circuit is less than or equal to the valley point voltage after rectification by the three-phase full-wave rectified power supply.

2. The high-voltage LED driving method according to claim 1, characterized in that: The LED module includes a high-voltage linearly driven LED module.

3. The high-voltage LED driving method according to claim 1 or 2, characterized in that: The light-emitting unit includes an LED chip or an LED lamp bead.

4. The high-voltage LED driving method according to claim 1, characterized in that: One terminal of the circuit loop is positive, and the other terminal is negative or grounded.

5. A high-voltage LED driving circuit for implementing the high-voltage LED driving method according to any one of claims 1-4, the high-voltage LED driving circuit comprising an LED module, the LED module comprising x light-emitting units electrically connected in sequence in the driving circuit, wherein the 1st to the ith light-emitting unit is connected in the first segment of the working circuit, the (i+1)th to the kth light-emitting unit is connected in the second segment of the working circuit, and so on, the mth to the xth light-emitting unit is connected in the Nth segment of the working circuit, the two poles of the driving circuit are respectively used to be electrically connected to the positive and negative poles of the power supply, wherein x and N are integers greater than 2, and i, k, and m are integers greater than or equal to 1; Its features are, The driving circuit further includes a high-voltage constant current and constant power chip, which comprises a constant power control module, a voltage comparison module, a bandgap reference voltage generation module, an error amplifier module, a logic control module, a power supply voltage regulation module, and N switching modules. The chip also has a voltage sampling port, N constant current output ports, and N output current value setting ports. One end of the constant power control module is connected to the voltage sampling port, and the other end is sequentially connected to the voltage comparison module, the error amplifier module, and the logic control module. The control terminals of the first to Nth switching modules are all connected to the logic control module, their input terminals are connected to the first to Nth output current value setting ports, and their output terminals are connected to the first to Nth constant current output ports. The voltage comparison module is also connected to the input terminals of the bandgap reference voltage generation module and the Nth switching module. Specifically, one pole of the first working circuit is electrically connected to one pole of the driving circuit, and the other pole is connected to the first constant current output port of the high-voltage constant current constant power chip. One pole of the second working circuit is electrically connected to the other pole of the first working circuit, and the other pole of the second working circuit is connected to the second constant current output port of the high-voltage constant current constant power chip. Similarly, one pole of the Nth working circuit is electrically connected to the other pole of the (N-1)th working circuit, and the other pole of the Nth working circuit is connected to the Nth constant current output port of the high-voltage constant current constant power chip. The high-voltage constant current constant power chip also has N internal reference voltage ports. Each internal reference voltage port is electrically connected to the other pole of the drive circuit through an external control resistor. The power supply is a three-phase full-wave rectified power supply. Under three-phase full-wave rectification power supply conditions, the current value of each constant current source is set by adjusting the N external control resistors corresponding to each constant current source to meet the total power P of the LED module. LED The condition for constancy: Is I =P LED / (Vf1 + Vf2 +…+ Vf I ) ; Among them, Is I These are the current values ​​of the first constant current source, Vf1, Vf2, ... Vf I These are the normal operating voltages of the first working circuit, the second working circuit, ..., the first working circuit, 1≤I≤N, and the normal operating voltage Vf1 of the first working circuit is less than or equal to the valley point voltage after rectification by the three-phase full-wave rectified power supply.

6. The high-voltage LED driving circuit according to claim 5, characterized in that: The switching module includes a MOSFET.

7. The high-voltage LED driving circuit according to claim 5, characterized in that: The constant power control module includes multiple constant power control sub-modules arranged in parallel.

8. The high-voltage LED driving circuit according to claim 5, characterized in that: The voltage comparison module includes multiple voltage comparison sub-modules arranged in parallel.

9. The high-voltage LED driving circuit according to claim 5, characterized in that: The high-voltage constant current and constant power chip also includes a low-voltage gating module, one end of which is connected to the voltage sampling port and the other end is connected to the voltage comparison module.

10. The high-voltage LED driving circuit according to claim 5, characterized in that... It also includes an over-temperature protection and under-voltage lockout module, which is connected to the bandgap reference voltage generation module.

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