Driving circuit with multipath BUCK output and lamp

Abstract

The embodiment of the utility model relates to the technical field of electronic circuits, and discloses a multi-path BUCK output drive circuit, which comprises an adjustable direct current power supply module, a multi-path BUCK module and a control module, the adjustable direct-current power supply module is connected with the multi-path BUCK module and is used for providing direct-current voltage for each path of BUCK module; the multi-path BUCK module is connected with the multi-path load module and is used for providing working voltage for the multi-path load module; the control module is connected with the multipath load module and the adjustable DC power supply module, and is used for obtaining the working voltage of each path in the multipath load module in real time, and adjusting the DC voltage output by the adjustable DC power supply module in real time according to the maximum working voltage in all the working voltages. Through the above mode, the embodiment of the utility model realizes the effects of continuously and dynamically adjusting the bus voltage, enabling the N paths of BUCK circuits to work in the optimal working state, ensuring that each path of output meets the required constant current state, and having the highest conversion efficiency.

Description

Technical Field

[0001] The embodiment of the utility model relates to the technical field of electronic circuits, and in particular to a driving circuit and a lamp with multi-channel BUCK outputs. Background Art

[0002] In the traditional method, the input of BUCK is a fixed constant voltage source, followed by N constant current power supplies to drive N LEDs. Because the load of the multiple constant current sources is LED, and the voltage range of LED is relatively wide, in order to meet the requirement of wide LED voltage range, VIN is generally required to be greater than or equal to the highest LED string voltage * Dmax (maximum duty cycle), so that the LED string with any lamp bead voltage can work in the maximum constant current load state.

[0003] However, the inventors of this application have found that in actual applications, the voltage of many LED lamp beads is not the maximum value, and the light string is composed of many LEDs connected in series, which will cause the duty cycle of the BUCK circuit to be relatively small and the efficiency of the entire conversion circuit to be low. When the difference between the input voltage and the output voltage is large, a larger BUCK inductor is required, resulting in a large size, low efficiency and high cost of the conversion circuit. There is another situation, that is, in the dimming application of LED, when the output power is relatively small, because the input voltage is fixed, the voltage of the LED light string is lower at this time, and more voltage drop needs to be dropped to the BUCK inductor.

[0004] Therefore, there is an urgent need for a driving circuit that can dynamically adjust the bus voltage so that N bucks can all work in the best working state under the condition of satisfying any output load. Utility Model Content

[0005] In view of the above problems, the embodiments of the present invention provide a driving circuit and a lamp with multi-channel BUCK outputs, which are used to solve the technical problems in the prior art that the bus voltage cannot be adjusted, the N-channel BUCK circuit cannot be in the optimal working state under the condition of satisfying any output load, and the conversion efficiency is poor.

[0006] According to one aspect of the embodiment of the utility model, a driving circuit with multiple BUCK outputs is provided, the driving circuit comprising:

[0007] Adjustable DC power supply module, multi-channel BUCK module and control module;

[0008] The adjustable DC power supply module is connected to the multiple BUCK modules and is used to provide a DC voltage to each BUCK module;

[0009] The multi-channel BUCK module is connected to the multi-channel load module and is used to provide working voltage for the multi-channel load module;

[0010] The control module is connected to the multi-channel load module and the adjustable DC power supply module, and is used to obtain the working voltage of each channel in the multi-channel load module in real time, and adjust the DC voltage output by the adjustable DC power supply module in real time according to the maximum working voltage among all the working voltages.

[0011] In an optional manner, the control module is specifically used to collect the working voltages of the multi-channel load modules and determine the maximum working voltage among all the working voltages; determine the target voltage based on the maximum working voltage and a preset voltage constant; and gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage.

[0012] In an optional manner, the control module is specifically used to gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage during the current detection cycle; in the next detection cycle, continue to collect the working voltages of the multiple load modules to determine the maximum working voltage among all the working voltages; determine the target voltage based on the maximum working voltage and a preset voltage constant; and gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage.

[0013] In an optional manner, the target voltage is the sum of the maximum operating voltage and a preset voltage constant.

[0014] In an optional manner, the preset voltage constant is calculated according to the duty cycle of the BUCK module and the load voltage drop of the driving circuit.

[0015] In an optional manner, the multi-channel load module is a multi-channel LED light string.

[0016] In an optional manner, the multi-channel load module includes N LED light strings; the multi-channel BUCK module includes N BUCK modules; one of the LED light strings is connected to one of the BUCK modules.

[0017] In an optional manner, the BUCK module includes a switch tube, an inductor, a capacitor and a resistor; the source of the switch tube is connected to the positive electrode of the output end of the adjustable DC power supply module, and the drain of the switch tube is connected to the cathode of the diode and one end of the inductor; the other end of the inductor is connected to one end of the capacitor, and the other end of the capacitor and the anode of the diode are connected to the negative electrode of the output end of the adjustable DC power supply module; the two ends of the inductor are connected to the two ends of the resistor, and the two ends of the resistor are the output ends of the BUCK module.

[0018] In an optional manner, the input ports of the control module are respectively connected to N LED light strings through LED interface circuits.

[0019] According to another aspect of the embodiment of the present utility model, a lamp is provided, and the lamp includes the above-mentioned driving circuit and a multi-channel load module.

[0020] The embodiment of the utility model is connected to a multi-channel BUCK module through an adjustable DC power supply module, which is used to provide a DC voltage for each BUCK module. The multi-channel BUCK module is connected to a multi-channel load module, which is used to provide a working voltage for the multi-channel load module. The control module is connected to the multi-channel load module and the adjustable DC power supply module, which is used to obtain the working voltage of each channel in the multi-channel load module in real time, and adjust the DC voltage output by the adjustable DC power supply module 101 in real time according to the maximum working voltage among all the working voltages. In this way, the minimum difference between the DC voltage input to the BUCK module and the output voltage can be obtained, thereby minimizing the BUCK inductance and greatly reducing the volume of the BUCK circuit. By dynamically adjusting the bus voltage of the multi-channel BUCK module 102, when the voltage of the LED light string is low, the voltage of the constant voltage source input by the BUCK module also becomes lower accordingly. When the working voltage of the LED light string changes slightly, the control module 103 will sample it in real time, and then continuously and dynamically adjust the voltage of the input constant voltage source according to the preset mathematical logic requirements, so that under the condition of satisfying any output load, the BUCKMOSFET voltage stress, the BUCK inductor voltage stress, and the BUCK freewheeling diode (or freewheeling MOSFET) voltage stress are minimized, and the N-channel BUCK modules all work in the best working state, thereby improving the conversion efficiency of the BUCK drive circuit. Furthermore, the embodiment of the utility model can also effectively reduce the conduction damage and switching loss of the BUCK switch tube in this way.

[0021] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limiting of the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0023] Figure 1 A schematic diagram of a circuit module of a driving circuit with multiple BUCK outputs provided by an embodiment of the utility model is shown;

[0024] Figure 2A schematic diagram of the circuit structure of a driving circuit with multiple BUCK outputs provided by another embodiment of the utility model is shown;

[0025] Figure 3 A schematic diagram of the circuit structure of a BUCK module of a driving circuit with multiple BUCK outputs provided in an embodiment of the utility model is shown;

[0026] Figure 4 A schematic structural diagram of a lamp provided by an embodiment of the utility model is shown.

[0027] The reference numerals in the specific implementation manner are as follows:

[0028] A lamp 10 , a driving circuit 100 with multiple BUCK outputs, an adjustable DC power supply module 101 , a multiple BUCK module 102 , a control module 103 , and a multiple load module 200 . DETAILED DESCRIPTION

[0029] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.

[0030] See also Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a circuit module of a driving circuit 100 with multiple BUCK outputs provided by an embodiment of the present utility model. Figure 1 As shown, the driving circuit 100 includes: an adjustable DC power supply module 101 , a multi-channel BUCK module 102 and a control module 103 .

[0031] The adjustable DC power supply module 101 is connected to the multiple BUCK modules 102 to provide a DC voltage to each BUCK module 102 .

[0032] The multi-channel BUCK module 102 is connected to the multi-channel load module 200 and is used to provide a working voltage for the multi-channel load module 200 .

[0033] The control module 103 is connected to the multi-channel load module 200 and the adjustable DC power supply module 101, and is used to obtain the working voltage of each channel in the multi-channel load module 200 in real time, and adjust the DC voltage output by the adjustable DC power supply module 101 in real time according to the maximum working voltage among all the working voltages.

[0034] In the embodiment of the utility model, the adjustable DC power supply module 101 (DC SOURCE) is a DC source with adjustable voltage, and the output DC voltage is controlled by the control module 103. The control module 103 samples the working voltage of each path in the multi-path load module 200, takes out the maximum voltage A of the N-path load module, determines the target voltage according to the maximum voltage A of the N-path load module, according to the maximum working voltage and the preset voltage constant, and then gradually adjusts the DC voltage output by the adjustable DC power supply module to the target voltage. In the process of adjusting the DC voltage output by the adjustable DC power supply module 101 to the target voltage, in order to avoid the problem of flickering due to sudden voltage change, the control module 103 sends an adjustment signal to the adjustable DC power supply module 101 according to the preset voltage adjustment step, and the adjustable DC power supply module 101 feeds back the current DC voltage to the control module 103 in real time, and the control module 103 continues to adjust until the current DC voltage fed back by the adjustable DC power supply module 101 is the target voltage, thereby completing the process of gradually adjusting the DC voltage to the target voltage. In one embodiment of the present invention, the target voltage is the sum of the maximum operating voltage A and a preset voltage constant. The preset voltage constant B is calculated based on the duty cycle of the BUCK module and the load voltage drop of the drive circuit. The preset voltage constant B is a constant in practical applications and can be obtained based on engineering application experience. Figure 2 As shown, in the embodiment of the utility model, the multi-channel load module 103 is a multi-channel LED light string. The multi-channel load module 103 includes N-channel LED light strings; the multi-channel BUCK module 103 includes N-channel BUCK modules; one channel of the LED light string is connected to one channel of the BUCK module. Figure 3As shown, the BUCK module includes a switch tube Q1, an inductor L1, a capacitor C1 and a resistor R1. The source of the switch tube Q1 is connected to the positive electrode (busbar) of the output end of the adjustable DC power supply module 101, and the drain of the switch tube Q1 is connected to the cathode of the diode D1 and one end of the L1 inductor; the other end of the inductor L1 is connected to one end of the capacitor C1, and the other end of the capacitor C1 and the anode of the diode D1 are connected to the negative electrode of the output end of the adjustable DC power supply module 101; the two ends of the inductor L1 are connected to the two ends of the resistor R1, and the two ends of the resistor R1 are the output ends of the BUCK module. The voltage output by the adjustable DC power supply module 101 samples the voltage of each LED1, LED2...LEDN. The control module 103 takes out the maximum voltage A of the N LEDs according to the voltage sampling values ​​of LED1, LED2...LEDN. The maximum voltage A of the N-way LED is added with a constant B; the value of A+B is used as the target voltage value of the adjustable DC power supply module 101, thereby adjusting the adjustable DC power supply module 101. The sampling and adjustment are continuous and uninterrupted. In the embodiment of the utility model, the minimum difference between the DC voltage input and the output voltage of the BUCK module can be obtained in this way, thereby minimizing the BUCK inductance and greatly reducing the volume of the BUCK circuit. By dynamically adjusting the bus voltage of the multi-way BUCK module 102, when the voltage of the LED light string is low, the voltage of the constant voltage source input by the BUCK module also becomes lower accordingly. When the working voltage of the LED light string changes slightly, the control module 103 will sample it in real time, and then according to the preset mathematical logic requirements, continuously and dynamically adjust the voltage of the input constant voltage source, so that under the condition of satisfying any output load, the BUCKMOSFET voltage stress, the BUCK inductor voltage stress, and the BUCK freewheeling diode (or freewheeling MOSFET) voltage stress are minimized, and the N-way BUCK modules all work in the best working state, thereby improving the conversion efficiency of the BUCK drive circuit. Furthermore, in this way, the embodiments of the present invention can also effectively reduce the conduction damage and switching loss of the BUCK switch tube.

[0035] Among them, in the embodiment of the utility model, the control module 103 is also provided with a detection cycle, and the DC voltage output by the adjustable DC power supply module 101 is gradually adjusted to the target voltage in the current detection cycle; in the next detection cycle, the working voltage of the multi-channel load module 200 is continuously collected to determine the maximum working voltage among all working voltages; the target voltage is determined according to the maximum working voltage and the preset voltage constant; and the DC voltage output by the adjustable DC power supply module is gradually adjusted to the target voltage. Among them, the control module 103 can be a GD32F303RC single-chip microcomputer. Among them, the specific implementation of the GD32F303RC single-chip microcomputer gradually adjusting the DC voltage output by the adjustable DC power supply module to the target voltage according to the sum of the maximum working voltage A and the preset voltage constant can be implemented by the program design of the existing single-chip microcomputer, and the embodiment of the utility model does not make specific limitations.

[0036] Figure 4 The schematic diagram of the structure of the lamp provided by the embodiment of the utility model is shown. The lamp 10 includes the driving circuit 100 and the multi-channel load module 200 of the above embodiment. Among them, the multi-channel load module 103 is a multi-channel LED light string. The multi-channel load module 103 includes N-channel LED light strings. The specific implementation method of the driving circuit 100 in the lamp 10 of the embodiment of the utility model is generally consistent with the specific implementation method of the driving circuit 100 in the above embodiment, which will not be repeated here.

[0037] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present invention should have the common meanings understood by technicians in the field to which the embodiments of the present invention belong.

[0038] In the description of the embodiments of the present invention, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the embodiments of the present invention and simplifying the description, and does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present invention.

[0039] In addition, the technical terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of the embodiments of the present utility model, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0040] In the description of the present embodiment, unless otherwise clearly specified and limited, the technical terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to the specific circumstances.

[0041] In the description of the present embodiment, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it; although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model, and they should all be included in the scope of the claims and description of the utility model. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The utility model is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A driving circuit with multiple BUCK outputs, characterized in that: The driving circuit comprises: Adjustable DC power supply module, multi-channel BUCK module and control module; The adjustable DC power supply module is connected to the multiple BUCK modules and is used to provide a DC voltage to each BUCK module; The multi-channel BUCK module is connected to the multi-channel load module and is used to provide working voltage for the multi-channel load module; The control module is connected to the multi-channel load module and the adjustable DC power supply module, and is used to obtain the working voltage of each channel in the multi-channel load module in real time, and adjust the DC voltage output by the adjustable DC power supply module in real time according to the maximum working voltage among all the working voltages.

2. The driving circuit according to claim 1, characterized in that: The control module is specifically used to collect the working voltages of the multi-channel load modules and determine the maximum working voltage among all the working voltages; determine the target voltage based on the maximum working voltage and a preset voltage constant; and gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage.

3. The driving circuit according to claim 2, characterized in that: The control module is specifically used to gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage during the current detection cycle; in the next detection cycle, continue to collect the working voltages of the multiple load modules to determine the maximum working voltage among all the working voltages; determine the target voltage based on the maximum working voltage and a preset voltage constant; and gradually adjust the DC voltage output by the adjustable DC power supply module to the target voltage.

4. The driving circuit according to claim 2, characterized in that: The target voltage is the sum of the maximum operating voltage and a preset voltage constant.

5. The driving circuit according to any one of claims 2 to 4, characterized in that: The preset voltage constant is calculated according to the duty cycle of the BUCK module and the load voltage drop of the driving circuit.

6. The driving circuit according to any one of claims 2 to 4, characterized in that: The multi-channel load module is a multi-channel LED light string.

7. The driving circuit according to claim 6, characterized in that: The multi-channel load module includes N LED light strings; the multi-channel BUCK module includes N BUCK modules; one of the LED light strings is connected to one of the BUCK modules.

8. The driving circuit according to claim 7, characterized in that: The BUCK module includes a switch tube, an inductor, a diode, a capacitor and a resistor; the source of the switch tube is connected to the positive electrode of the output end of the adjustable DC power supply module, and the drain of the switch tube is connected to the cathode of the diode and one end of the inductor; the other end of the inductor is connected to one end of the capacitor, and the other end of the capacitor and the anode of the diode are connected to the negative electrode of the output end of the adjustable DC power supply module; the two ends of the inductor are connected to the two ends of the resistor, and the two ends of the resistor are the output ends of the BUCK module.

9. The driving circuit according to claim 1, characterized in that: The input ports of the control module are connected to N LED light strings through LED interface circuits respectively.

10. A lamp, characterized in that: The lamp comprises a driving circuit and a multi-channel load module as described in any one of claims 1 to 9.

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