Driving power supply with multifunctional protection circuit

Abstract

A driving power supply with a multifunctional protection circuit comprises a rectification module, a conversion module and an output filtering module. The rectifier module is connected with an external power supply. The conversion module is connected with the rectification module. The output filtering module is connected with a load and comprises a filtering unit and a protection unit. The filtering unit is connected with the conversion module. The protection unit is connected with the filtering unit and the conversion module. The protection unit comprises a current limiting assembly and a switch assembly which are connected in parallel.

Description

Technical Field

[0001] The invention relates to a driving power supply, in particular to a driving power supply with a multifunctional protection circuit. Background Art

[0002] As environmental awareness increases, more energy-efficient light-emitting diode (LED) lighting devices have become mainstream and continue to undergo substantial improvements. During this process, improvements to the driving power of LED lighting devices have also become a current development trend. Among them, how to ensure the quality of the driving power and reduce the impact of input inrush current on the driving power has become an important issue.

[0003] At present, many LED driving power supplies are not fully considered in the design of inrush current control. Excessive inrush current can easily lead to overload, which greatly increases the possibility of fire.

[0004] In addition, the circuit design of most LED driver power supplies usually includes an open circuit protection mechanism, and the open circuit protection voltage is usually 30% higher than the normal operating voltage, which puts higher voltage requirements on the selection of filter capacitors. Electrolytic capacitors with higher voltage resistance will increase costs, and these electrolytic capacitors are not conducive to circuit design due to their large size. Summary of the invention

[0005] According to one embodiment of the present invention, a driving power supply with a multifunctional protection circuit is provided, which includes a rectifier module, a conversion module and an output filter module. The rectifier module is connected to an external power supply. The conversion module is connected to the rectifier module. The output filter module is connected to a load and includes a filter unit and a protection unit. The filter unit is connected to the conversion module. The protection unit is connected to the filter unit and the conversion module. The protection unit includes a current limiting component and a switch component connected in parallel.

[0006] In one embodiment, the load includes a plurality of light sources connected in series. The switch component is connected to a power supply node, and the power supply node is arranged between the plurality of light sources.

[0007] In one embodiment, one end of the current limiting component and the first end of the switch component are connected to the first node, and the other end of the current limiting component and the second end of the switch component are connected to the second node. The third end of the switch component is connected to the third node. The first node is connected to the filter unit. The second node is connected to the conversion module. The third node is connected to the power supply node.

[0008] In one embodiment, the protection unit further includes a control resistor. The third node is connected to the power supply node through the control resistor.

[0009] In one embodiment, the protection unit further includes a discharge resistor, one end of which is connected to the third node, and the other end of which is connected to the second node.

[0010] In one embodiment, the rectifier module receives an input voltage from an external power source to generate a rectified voltage, and the conversion module converts the rectified voltage to generate a driving voltage to charge the filter unit. The switch component is turned off when the filter unit is charged.

[0011] In one embodiment, the switch component is turned on when the load enters an operating state, so that the current limiting component enters a short-circuit state.

[0012] In one embodiment, the switch component is turned off when the load enters an open circuit state.

[0013] In one embodiment, the current limiting component is a thermistor.

[0014] In one embodiment, the filter unit is an electrolytic capacitor.

[0015] As described above, the driving power supply with a multifunctional protection circuit according to the embodiment of the present invention may have one or more of the following advantages:

[0016] (1) In one embodiment of the present invention, the driving power supply includes a rectifier module, a conversion module and an output filter module. The rectifier module is connected to an external power supply. The conversion module is connected to the rectifier module. The output filter module is connected to the load and includes a filter unit and a protection unit. The filter unit is connected to the conversion module. The protection unit is connected to the filter unit and the conversion module. The protection unit includes a current limiting component and a switch component connected in parallel. The rectifier module receives an input voltage from an external power supply to generate a rectified voltage, and the conversion module converts the rectified voltage to generate a driving voltage to charge the filter unit. The switch component is turned off when the filter unit is charged. The above-mentioned protection unit can be used as an effective protection circuit, so that the current limiting component is connected in series with the filter unit when the filter unit is charged to provide a current limiting effect, which can effectively reduce the inrush current to prevent overload. Therefore, the safety of the driving power supply can be greatly improved.

[0017] (2) In one embodiment of the present invention, the output filter module of the driving power supply includes a protection unit, and the protection unit includes a current limiting component and a switch component connected in parallel. The switch component is turned on when the load enters the operating state, so that the current limiting component enters a short-circuit state. Through the above mechanism, the protection unit can temporarily short-circuit the current limiting component when the switch component enters the operating state of the load to prevent energy loss. Therefore, the operating efficiency of the driving power supply can be greatly improved without affecting its safety.

[0018] (3) In one embodiment of the present invention, the output filter module of the driving power supply includes a protection unit, and the protection unit includes a current limiting component and a switch component connected in parallel. The switch component is turned off when the load enters an open circuit state, so that the open circuit voltage is applied to the filter unit and the current limiting component at the same time. At this time, the current limiting component can provide a voltage dividing effect to reduce the voltage borne by the filter unit. The above mechanism can effectively prevent the filter unit from being damaged due to high voltage, thereby improving the reliability and service life of the driving power supply. In addition, the filter unit does not need to use a capacitor with a high withstand voltage value, so that the cost of the driving power supply is further reduced.

[0019] (4) In one embodiment of the present invention, the output filter module of the driving power supply includes a protection unit, and the protection unit includes a current limiting component and a switch component connected in parallel. The current limiting component can be a thermistor. Therefore, when the temperature rises, the resistance value of the current limiting component also increases, so that the voltage dividing effect of the current limiting component is improved to further reduce the voltage borne by the filter unit. Therefore, the reliability and service life of the driving power supply can be further improved, and the cost of the driving power supply can also be further reduced.

[0020] (5) In one embodiment of the present invention, the output filter module of the driving power supply includes a protection unit, and the protection unit includes a current limiting component and a switch component connected in parallel. One end of the current limiting component and the first end of the switch component are connected to the first node, and the other end of the current limiting component and the second end of the switch component are connected to the second node. The third end of the switch component is connected to the third node. The first node is connected to the filtering unit. The second node is connected to the conversion module, and the third node is connected to the power supply node. The protection unit may also include a control resistor. The third node is connected to the power supply node through the control resistor. The above circuit design can reduce the impact of the switch component on the brightness of the load when it is turned on. Therefore, the load can still achieve high efficiency to meet the needs of practical applications.

[0021] (6) In one embodiment of the present invention, the protection unit of the output filter module of the driving power supply may further include a discharge resistor. One end of the discharge resistor is connected to the third node, and the other end of the discharge resistor is connected to the second node. The discharge resistor can discharge to turn off the switch component when the load enters the open circuit state, so as to ensure that the switch component is turned off in time when the load enters the open circuit state. Therefore, the discharge resistor can ensure that the current limiting component can provide a voltage dividing effect to reduce the voltage borne by the filter unit, so as to effectively prevent the filter unit from being damaged due to being borne by high voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. 4 is a block diagram of a circuit structure of a driving power supply with a multi-functional protection circuit according to a first embodiment of the present invention.

[0023] Figure 2FIG. 4 is a circuit diagram of a driving power supply with a multi-functional protection circuit according to a second embodiment of the present invention.

[0024] Figure 3 FIG. 4 is a circuit diagram of a driving power supply with a multi-functional protection circuit according to a third embodiment of the present invention.

[0025] Description of reference numerals:

[0026] 1-driving power supply; 10-input module; 11-rectifier module; 12-conversion module; 13-output filter module; 131-filter unit; 132-protection unit; 1321-current limiting component; 1322-switch component; Lt-live line input terminal; Nt-neutral line input terminal; BD1-rectifier bridge; C1-first capacitor; C2-second capacitor; C3-third capacitor; EC1-electrolytic capacitor; R1-first resistor; R2-second resistor; R3-third resistor; R4-fourth resistor; R5-fifth resistor; Rc-control resistor; Rf-discharge resistor; Rt-thermistor; L1-first inductor; L2-second inductor; U1-controller; D1-first diode; D2-second diode; Q1-first switch; Qs-transistor; GND-ground point; LD-load; V+-positive terminal of load; V--negative terminal of load; LS-light emitting diode; PS-external power supply; N1-first node; N2-second node; N3-third node; Np-power supply node.

[0027] The detailed features and advantages of the present invention are described in detail in the following embodiments, and the contents are sufficient to enable anyone skilled in the relevant art to understand the technical content of the present invention and implement it accordingly. Moreover, according to the contents, claims and drawings disclosed in this specification, any person skilled in the relevant art can easily understand the purposes and advantages of the present creation. DETAILED DESCRIPTION

[0028] The following will refer to the relevant drawings to illustrate the embodiment of the driving power supply with a multifunctional protection circuit according to the present invention. For the sake of clarity and convenience of the diagram description, the components in the drawings may be exaggerated or reduced in size and proportion. In the following description and / or claims, when it is mentioned that a component is "connected" or "coupled" to another component, it may be directly connected or coupled to the other component or there may be an intervening component; and when it is mentioned that a component is "directly connected" or "directly coupled" to another component, there is no intervening component, and other words used to describe the relationship between components or layers should be interpreted in the same way. For ease of understanding, the same components in the following embodiments are illustrated with the same symbols.

[0029] See also Figure 1, which is a block diagram of the circuit structure of the driving power supply with a multifunctional protection circuit according to the first embodiment of the present invention. As shown in the figure, the driving power supply 1 includes an input module 10, a rectifier module 11, a conversion module 12 and an output filter module 13.

[0030] The rectifier module 11 is connected to the external power source PS through the input module 10. In one embodiment, the external power source PS can be a mains supply, a generator or other similar power sources. In one embodiment, the rectifier module 11 includes one or more of a rectifier and a filter circuit.

[0031] The conversion module 12 is connected to the rectification module 11. In one embodiment, the conversion module 12 may be a DC / DC converter, such as a boost converter, a buck converter, a buck-boost converter or other similar components.

[0032] The output filter module 13 is connected to the load LD and includes a filter unit 131 and a protection unit 132. The filter unit 131 is connected to the conversion module 12. The protection unit 132 is connected to the filter unit 131 and the conversion module 12. The protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel with each other. In one embodiment, the load LD includes a plurality of light sources connected to each other. The light sources may be connected in series or in parallel. In another embodiment, a part of the light sources are connected in series, and another part of the light sources are connected in parallel. In one embodiment, the plurality of light sources may be light emitting diodes Ls. The switch component 1322 is connected to the power supply node Np, and the power supply node Np is arranged between the plurality of light sources. In one embodiment, the current limiting component 1321 is a resistor, a thermistor Rt or other similar components. In one embodiment, the switch component 1322 is a metal oxide semi-field effect transistor (MOSFET), a triode (BJT) or other similar components. In one embodiment, the filter unit 131 is an electrolytic capacitor EC1 or other components with energy storage function.

[0033] The rectifier module 11 receives the input voltage of the external power source PS through the input module 10 to generate a rectified voltage. The conversion module 12 converts the rectified voltage to generate a driving voltage to charge the filter unit 131. When the filter unit 131 is charged, the switch component 1322 is turned off. At this time, the protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect. Therefore, the protection unit 132 can effectively reduce the inrush current.

[0034] When the load LD enters the operating state, the switch component 1322 is turned on, causing the current limiting component 1321 to enter the short circuit state. At this time, the protection unit 132 can temporarily short the current limiting component 1321 when the load LD enters the operating state to prevent energy loss.

[0035] When the load LD enters the open circuit state, the switch component 1322 is turned off again. At this time, the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131.

[0036] As can be seen from the above, the protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect, which can effectively reduce the inrush current to prevent overload. Therefore, the safety of the driving power supply 1 can be greatly improved.

[0037] In addition, in this embodiment, the protection unit 132 can temporarily short-circuit the current limiting component 1321 when the switch component 1322 enters the operating state to prevent energy loss. Therefore, the operating efficiency of the driving power supply 1 can be greatly improved without affecting its safety.

[0038] In addition, in the present embodiment, the switch component 1322 is turned off when the load LD enters the open circuit state, so that the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131. The above mechanism can effectively prevent the filter unit 131 from being damaged due to high voltage, thereby improving the reliability and service life of the driving power supply 1. In addition, the filter unit 131 does not need to use a capacitor with a high withstand voltage value, so that the cost of the driving power supply 1 is further reduced.

[0039] From the above, it can be seen that the protection unit 132 is indeed a multi-functional protection circuit with a multi-functional protection mechanism.

[0040] Of course, this embodiment is only used for illustration and does not limit the scope of the present invention. Equivalent modifications or changes made to the driving power supply with a multi-functional protection circuit according to this embodiment should still be included in the patent scope of the present invention.

[0041] See also Figure 2 , which is a circuit diagram of a driving power supply with a multifunctional protection circuit according to a second embodiment of the present invention. As shown in the figure, the driving power supply 1 includes an input module 10, a rectifier module 11, a conversion module 12 and an output filter module 13.

[0042] The rectifier module 11 is connected to the external power supply PS through the input module 10. In the present embodiment, the input module 10 includes a live input terminal Lt and a neutral input terminal Nt. A fuse (not shown in the figure) may also be provided between the rectifier module 11 and the input module 10. In the present embodiment, the external power supply PS is a mains supply. In the present embodiment, the rectifier module 11 includes a rectifier bridge BD1 and a filter circuit including a first capacitor C1, a first resistor R1, a first inductor L1 and a second capacitor C2. The circuit structure and operation mechanism of the rectifier module 11 should be well known to those skilled in the art, so they will not be elaborated here.

[0043] The conversion module 12 is connected to the rectifier module 11. In the present embodiment, the conversion module 12 may be a DC / DC converter (GND represents a grounding point) including a second resistor R2, a third resistor R3, a third capacitor C3, a controller U1, a fourth resistor R4, a fifth resistor R5, a second inductor L2, a first diode D1, a second diode D2 and a first switch Q1 (metal oxide semiconductor field effect transistor). In one embodiment, the controller U1 may be a microcontroller (MCU), a central processing unit (CPU), an application specific integrated circuit chip (ASIC), a field programmable gate array (FPGA) or other similar components. The circuit structure and operation mechanism of the above-mentioned conversion module 12 should be well known to those skilled in the art, so they will not be elaborated here.

[0044] The output filter module 13 is connected to the positive terminal V+ and the negative terminal V- of the load LD, and includes a filter unit 131 and a protection unit 132. The filter unit 131 is connected to the conversion module 12. The protection unit 132 is connected to the filter unit 131 and the conversion module 12. The protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel. In this embodiment, the load LD includes a plurality of light emitting diodes LS connected in series.

[0045] One end of the current limiting component 1321 and the first end of the switch component 1322 are connected to the first node N1, and the other end of the current limiting component 1321 and the second end of the switch component 1322 are connected to the second node N2. The third end of the switch component 1322 is connected to the third node N3. The first node N1 is connected to the filter unit 131. The second node N2 is connected to the conversion module 132. The third node N3 is connected to the power supply node Np.

[0046] Similarly, the rectifier module 11 receives the input voltage of the external power source PS through the input module 10 to generate a rectified voltage. The conversion module 12 converts the rectified voltage to generate a driving voltage to charge the filter unit 131. When the filter unit 131 is charged, the switch component 1322 is turned off. At this time, the protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect. Therefore, the protection unit 132 can effectively reduce the inrush current.

[0047] When the load LD enters the operating state, the switch component 1322 is turned on, causing the current limiting component 1321 to enter the short circuit state. At this time, the protection unit 132 can temporarily short the current limiting component 1321 when the load LD enters the operating state to prevent energy loss.

[0048] When the load LD enters the open circuit state, the switch component 1322 is turned off again. At this time, the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131.

[0049] Of course, this embodiment is only used for illustration and does not limit the scope of the present invention. Equivalent modifications or changes made to the driving power supply with a multi-functional protection circuit according to this embodiment should still be included in the patent scope of the present invention.

[0050] See also Figure 3 , which is a circuit diagram of a driving power supply with a multifunctional protection circuit according to a third embodiment of the present invention. As shown in the figure, the driving power supply 1 includes an input module 10, a rectifier module 11, a conversion module 12 and an output filter module 13.

[0051] The rectifier module 11 is connected to the external power supply PS through the input module 10. In the present embodiment, the input module 10 includes a live input terminal Lt and a neutral input terminal Nt. A fuse (not shown in the figure) may also be provided between the rectifier module 11 and the input module 10. In the present embodiment, the external power supply PS is a mains supply. In the present embodiment, the rectifier module 11 includes a rectifier bridge BD1 and a filter circuit including a first capacitor C1, a first resistor R1, a first inductor L1 and a second capacitor C2. The circuit structure and operation mechanism of the rectifier module 11 should be well known to those skilled in the art, so they will not be elaborated here.

[0052] The conversion module 12 is connected to the rectifier module 11. In the present embodiment, the conversion module 12 may be a DC / DC converter including a second resistor R2, a third resistor R3, a third capacitor C3, a controller U1, a fourth resistor R4, a fifth resistor R5, a second inductor L2, a first diode D1, a second diode D2 and a first switch Q1 (GND represents a grounding point). In one embodiment, the controller U1 may be a microcontroller (MCU), a central processing unit (CPU), an application-specific integrated circuit chip (ASIC), a field programmable gate array (FPGA) or other similar components. The circuit structure and operation mechanism of the above-mentioned conversion module 12 should be well known to those skilled in the art, so they will not be described in detail here.

[0053] The output filter module 13 is connected to the positive terminal V+ and the negative terminal V- of the load LD, and includes a filter unit 131 and a protection unit 132. The filter unit 131 is connected to the conversion module 12. In the present embodiment, the filter unit 131 is an electrolytic capacitor EC1. The protection unit 132 is connected to the filter unit 131 and the conversion module 12. The protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel with each other. In addition, the protection unit 132 also includes a control resistor Rc and a discharge resistor Rf. In the present embodiment, the current limiting component 1321 is a thermistor Rt, and the switch component 1322 is a transistor Qs (metal oxide semi-conductor field effect transistor). In the present embodiment, the load LD includes a plurality of light-emitting diodes LS connected in series with each other.

[0054] One end of the current limiting component 1321 and the drain (first end) of the switch component 1322 are connected to the first node N1, and the other end of the current limiting component 1321 and the source (second end) of the switch component 1322 are connected to the second node N2. The gate (third end) of the switch component 1322 is connected to the third node N3. The first node N1 is connected to the filter unit 131. The second node N2 is connected to the conversion module 12. The third node N3 is connected to the power supply node Np through the control resistor Rc. One end of the discharge resistor Rf is connected to the third node N3, and the other end of the discharge resistor Rf is connected to the second node N2. In this embodiment, the voltage of the power supply node Np is equal to the cross-voltage of the two light-emitting diodes LS (the position of the power supply node Np can be adjusted according to actual needs), and this voltage must be sufficient to drive the switch component 1322.

[0055] Similarly, the rectifier module 11 receives the input voltage of the external power source PS through the input module 10 to generate a rectified voltage. The conversion module 12 converts the rectified voltage to generate a driving voltage to charge the filter unit 131. When the filter unit 131 is charged, the switch component 1322 is turned off. At this time, the protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect. Therefore, the protection unit 132 can effectively reduce the inrush current.

[0056] When the load LD enters the operating state, the switch component 1322 is turned on, so that the current limiting component 1321 enters the short circuit state. At this time, the protection unit 132 can temporarily short-circuit the current limiting component 1321 when the load LD enters the operating state to prevent energy loss. Since the control resistor Rc is set between the third node N3 and the power supply node Np, the current that drives the switch component 1322 to conduct can be suppressed to avoid affecting the brightness of the load LD.

[0057] When the load LD enters the open circuit state, the discharge resistor Rf discharges to turn off the switch component 1322, so as to ensure that the switch component 1322 is turned off in time when the load LD enters the open circuit state. At this time, the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131.

[0058] As can be seen from the above, the protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect, which can effectively reduce the inrush current to prevent overload. Therefore, the safety of the driving power supply 1 can be greatly improved.

[0059] In this embodiment, the protection unit 132 can temporarily short-circuit the current limiting component 1321 when the switch component 1322 enters the operating state to prevent energy loss. Therefore, the operating efficiency of the driving power supply 1 can be greatly improved without affecting its safety.

[0060] In addition, in the present embodiment, the switch component 1322 is turned off when the load LD enters the open circuit state, so that the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131. The above mechanism can effectively prevent the filter unit 131 from being damaged due to high voltage, thereby improving the reliability and service life of the driving power supply 1. In addition, the filter unit 131 does not need to use a capacitor with a high withstand voltage value, so that the cost of the driving power supply 1 is further reduced.

[0061] In addition, in this embodiment, the above circuit design can reduce the influence of the switch element 1322 on the brightness of the load LD when it is turned on. Therefore, the load LD can still achieve high performance to meet the requirements of practical applications.

[0062] Furthermore, in this embodiment, the discharge resistor Rf can ensure that the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131, so as to effectively prevent the filter unit 131 from being damaged due to being borne by the high voltage.

[0063] From the above, it can be seen that the protection unit 132 is indeed a multi-functional protection circuit with a multi-functional protection mechanism.

[0064] Of course, this embodiment is only used for illustration and does not limit the scope of the present invention. Equivalent modifications or changes made to the driving power supply with a multi-functional protection circuit according to this embodiment should still be included in the patent scope of the present invention.

[0065] In summary, according to an embodiment of the present invention, the driving power supply 1 includes a rectifier module 11, a conversion module 12 and an output filter module 13. The rectifier module 11 is connected to the external power supply PS. The conversion module 12 is connected to the rectifier module 11. The output filter module 13 is connected to the load LD and includes a filter unit 131 and a protection unit 132. The filter unit 131 is connected to the conversion module 12. The protection unit 132 is connected to the filter unit 131 and the conversion module 12. The protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel with each other. The rectifier module 11 receives an input voltage from the external power supply PS to generate a rectified voltage, and the conversion module 12 converts the rectified voltage to generate a driving voltage to charge the filter unit 131. The switch component 1322 is turned off when the filter unit 131 is charged. The protection unit 132 can be used as an effective protection circuit, so that the current limiting component 1321 is connected in series with the filter unit 131 when the filter unit 131 is charged to provide a current limiting effect, which can effectively reduce the inrush current to prevent overload. Therefore, the safety of the driving power supply 1 can be greatly improved.

[0066] According to an embodiment of the present invention, the output filter module 13 of the driving power supply 1 includes a protection unit 132, and the protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel. This switch component 1322 is turned on when the load LD enters the operating state, so that the current limiting component 1321 enters a short-circuit state. Through the above mechanism, the protection unit 132 can temporarily short-circuit the current limiting component 1321 when the switch component 1322 enters the operating state when the load LD enters the operating state to prevent energy loss. Therefore, the operating efficiency of the driving power supply 1 can be greatly improved without affecting its safety.

[0067] Furthermore, according to an embodiment of the present invention, the output filter module 13 of the driving power supply 1 includes a protection unit 132, and the protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel. This switch component 1322 is turned off when the load LD enters an open circuit state, so that the open circuit voltage is applied to the filter unit 131 and the current limiting component 1321 at the same time. At this time, the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131. The above mechanism can effectively prevent the filter unit 131 from being damaged due to high voltage, thereby improving the reliability and service life of the driving power supply 1. In addition, the filter unit 131 does not need to use a capacitor with a high withstand voltage value, so that the cost of the driving power supply 1 is further reduced.

[0068] In addition, according to an embodiment of the present invention, the output filter module 13 of the driving power supply 1 includes a protection unit 132, and the protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel. The current limiting component 1321 can be a thermistor Rt. Therefore, when the temperature increases, the resistance value of the current limiting component 1321 also increases, so that the voltage dividing effect of the current limiting component 1321 is improved to further reduce the voltage borne by the filter unit 131. Therefore, the reliability and service life of the driving power supply 1 can be further improved, and the cost of the driving power supply 1 can also be further reduced.

[0069] In addition, according to an embodiment of the present invention, the output filter module 13 of the driving power supply 1 includes a protection unit 132, and the protection unit 132 includes a current limiting component 1321 and a switch component 1322 connected in parallel. One end of the current limiting component 1321 and the first end of the switch component 1322 are connected to the first node N1, and the other end of the current limiting component 1321 and the second end of the switch component 1322 are connected to the second node N2. The third end of the switch component 1322 is connected to the third node N3. The first node N1 is connected to the filtering unit 131. The second node N2 is connected to the conversion module 12, and the third node N3 is connected to the power supply node Np. The protection unit 132 may also include a control resistor Rc. The third node N3 is connected to the power supply node Np through the control resistor Rc. The above circuit design can reduce the influence of the switch component 1322 on the brightness of the load LD when it is turned on. Therefore, the load LD can still achieve high efficiency to meet the needs of practical applications.

[0070] Furthermore, according to an embodiment of the present invention, the protection unit 132 of the output filter module 13 of the driving power supply 1 may further include a discharge resistor Rf. One end of the discharge resistor Rf is connected to the third node N3, and the other end of the discharge resistor Rf is connected to the second node N2. The discharge resistor can discharge to turn off the switch component 1322 when the load LD enters the open circuit state, so as to ensure that the switch component 1322 is turned off in time when the load LD enters the open circuit state. Therefore, the discharge resistor Rf can ensure that the current limiting component 1321 can provide a voltage dividing effect to reduce the voltage borne by the filter unit 131, so as to effectively prevent the filter unit 131 from being damaged due to being subjected to a high voltage.

[0071] It should be noted that, although the above embodiments have been described in this article, the scope of patent protection of the present invention is not limited thereby. Therefore, based on the innovative concept of the present invention, changes and modifications made to the embodiments described herein, or equivalent structures or equivalent process changes made using the contents of the present specification and drawings, directly or indirectly applying the above technical solutions to other related technical fields are all included in the scope of protection of the patent of the present invention.

Claims

1. A driving power supply with a multifunctional protection circuit, characterized in that: include: A rectifier module connected to an external power source; A conversion module, connected to the rectifier module; as well as The output filter module is connected to the load and includes a filter unit and a protection unit. The filter unit is connected to the conversion module. The protection unit is connected to the filter unit and the conversion module. The protection unit includes a current limiting component and a switch component connected in parallel.

2. The driving power supply with a multifunctional protection circuit as claimed in claim 1, characterized in that: The load includes a plurality of light sources connected in series, the switch component is connected to a power supply node, and the power supply node is arranged between the plurality of light sources.

3. The driving power supply with a multifunctional protection circuit as claimed in claim 2, characterized in that: One end of the current limiting component and the first end of the switch component are connected to a first node, the other end of the current limiting component and the second end of the switch component are connected to a second node, the third end of the switch component is connected to a third node, the first node is connected to the filtering unit, the second node is connected to the conversion module, and the third node is connected to the power supply node.

4. The driving power supply with a multifunctional protection circuit as claimed in claim 3, characterized in that: The protection unit further includes a control resistor, and the third node is connected to the power supply node through the control resistor.

5. The driving power supply with a multifunctional protection circuit as claimed in claim 3, characterized in that: The protection unit further includes a discharge resistor, one end of the discharge resistor is connected to the third node, and the other end of the discharge resistor is connected to the second node.

6. The driving power supply with a multifunctional protection circuit as claimed in claim 1, characterized in that: The rectifier module receives the input voltage of the external power supply to generate a rectified voltage, the conversion module converts the rectified voltage to generate a driving voltage to charge the filter unit, and the switch component is turned off when the filter unit is charged.

7. The driving power supply with a multifunctional protection circuit as claimed in claim 6, characterized in that: The switch component is turned on when the load enters an operating state, so that the current limiting component enters a short-circuit state.

8. The driving power supply with a multifunctional protection circuit as claimed in claim 7, characterized in that: The switch component is turned off when the load enters an open circuit state.

9. The driving power supply with a multifunctional protection circuit as claimed in claim 1, characterized in that: The current limiting component is a thermistor.

10. The driving power supply with a multifunctional protection circuit as claimed in claim 1, characterized in that: The filter unit is an electrolytic capacitor.

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