DALI-based self-recovery short-circuit protection circuit and dimming illumination lamp

Abstract

The utility model provides a self-recovery short-circuit protection circuit based on a DALI protocol, and the circuit comprises a drive circuit, a short-circuit detection circuit, a DALI control circuit, a detection resistor, a first electronic switching tube, and a constant-voltage lamp strip. One end of the detection resistor is connected with the output of the driving circuit, the other end of the detection resistor is connected to the short-circuit detection circuit and the first electronic switch tube, the other end of the first electronic switch tube is connected with the constant-voltage lamp strip, and the control end of the first electronic switch tube is connected with the PWM end of the DALI control circuit; when the circuit is short-circuited, the voltage of the short-circuit signal receiving end in the DALI control circuit is pulled to a low level, so that the MCU is prompted to quickly turn off the first electronic switch tube by using an interruption function, and the problem that the first electronic switch tube is broken down due to the fact that the output end is not detected to be abnormal in time is effectively prevented. In addition, the MCU in the DALI control circuit can circularly detect the short-circuit signal state, and enables the circuit to automatically recover normal work after the short-circuit fault is eliminated.

Description

Technical Field

[0001] The present disclosure relates to the technical field of driver protection, and particularly to a DALI-based self-recovery short-circuit protection circuit and a dimming lighting fixture. Background Art

[0002] In an intelligent lighting system, DALI (Digital Addressable Lighting Interface), as an advanced lighting control protocol, has been widely applied in various lighting projects, which puts forward higher requirements for the compatibility and performance of DALI drivers and control systems. The traditional DALI constant-voltage dimming drive power supply design usually includes a single-chip microcomputer control circuit and a dimming MOS transistor, and the brightness of the LED is controlled by adjusting the PWM signal.

[0003] When a short circuit occurs in the existing drive power supply, since the dimming MOS transistor is directly connected between the load and the power supply output, and the dimming MOS transistor is located after the power conversion module, it is difficult for the front-stage control circuit to quickly detect the abnormality at the output end, so that the front-stage control circuit may continue to supply power to the circuit, which easily causes the dimming MOS transistor to be damaged due to excessive current, and manual power-on is required again after the short circuit to resume normal operation.

[0004] For example, the comparative document CN202120366344.X discloses a drive power supply circuit with a short-circuit protection function, including an AC input and EMI circuit, a bridge full-wave rectification module, a PFC control circuit, an LLC control circuit, an LED drive circuit with a DALI module, and an output end. The input end of the AC input and EMI circuit is connected to an AC power supply, the output end of the AC input and EMI circuit is connected to the input end of the bridge full-wave rectification module, the output end of the bridge full-wave rectification module is connected to the input end of the PFC control circuit, the output end of the PFC control circuit is connected to the input end of the LLC control circuit, a short-circuit protection circuit is connected in series between the output end of the LLC control circuit and the output end, and the LED drive circuit is used to output working power to the load end. Under normal circumstances, the short-circuit protection circuit does not work, the MOS transistor Q14 remains conducting, and the LED drive power supply normally supplies power to the load, and the LLC control circuit, the LED drive circuit, and the DALI module all work normally; when a short circuit occurs, the short-circuit protection circuit quickly acts to cut off the output circuit, and at this time, the LLC control circuit, the LED drive circuit, and the DALI module still remain in the working state. However, manual power-on is required again after the short circuit to resume normal operation in this solution, which is not suitable for application in an intelligent scenario. Summary of the Utility Model

[0005] The purpose of the present disclosure is to overcome the deficiencies in the prior art, and to provide a DALI-based self-recovery short-circuit protection circuit and a dimming lighting fixture that can quickly turn off the MOS transistor and automatically restore the working state.

[0006] The object of the present disclosure is achieved by the following technical solutions:

[0007] A self - recovery short - circuit protection circuit based on DALI includes a driving circuit, a short - circuit detection circuit, a DALI control circuit, and a constant - voltage light strip. The driving circuit is used to supply power to the constant - voltage light strip;

[0008] The self - recovery short - circuit protection circuit based on DALI further includes a detection resistor and a first electronic switch tube. The first end of the detection resistor is connected to the output end of the driving circuit, the second end of the detection resistor is connected to the short - circuit detection end of the short - circuit detection circuit, the second end of the detection resistor is also connected to the first end of the first electronic switch tube, the second end of the first electronic switch tube is connected to the constant - voltage light strip, the control end of the first electronic switch tube is connected to the PWM output end of the DALI control circuit, and the short - circuit detection circuit is connected to the short - circuit signal receiving end of the DALI control circuit.

[0009] The short - circuit detection circuit includes a first resistor, a second resistor, a third resistor, and a second electronic switch tube. The first end of the first resistor is connected to the second end of the detection resistor, the second end of the first resistor is respectively connected to the first end of the second resistor and the control end of the second electronic switch tube, the second end of the second resistor and the second end of the second electronic switch tube are both connected to the ground terminal, the first end of the second electronic switch tube is respectively connected to the first end of the third resistor and the short - circuit signal receiving end of the DALI control circuit, and the second end of the third resistor is used to be connected to an external power supply terminal.

[0010] In one embodiment, the short - circuit detection circuit further includes a first capacitor. The first end of the first capacitor is connected to the short - circuit signal receiving end of the DALI control circuit, and the second end of the first capacitor is grounded.

[0011] In one embodiment, the first electronic switch tube is an N - channel MOS tube. The drain of the first electronic switch tube is connected to the second end of the detection resistor, the source of the first electronic switch tube is connected to the constant - voltage light strip, and the gate of the first electronic switch tube is connected to the PWM output end of the DALI control circuit.

[0012] In one embodiment, the driving circuit includes a rectification module. The input end of the rectification module is connected to industrial frequency alternating current, and the output end of the rectification module is connected to the constant - voltage light strip.

[0013] In one embodiment, the drive circuit further includes an active power factor correction circuit module. The input end of the active power factor correction circuit module is connected to the output end of the rectification module, and the output end of the active power factor correction circuit module is connected to the constant voltage LED strip.

[0014] In one embodiment, the drive circuit further includes a power conversion isolation module. The input end of the power conversion isolation module is connected to the output end of the active power factor correction circuit module, and the output end of the power conversion isolation module is connected to the constant voltage LED strip.

[0015] In one embodiment, the drive circuit further includes a first polarized capacitor. The positive electrode of the first polarized capacitor is connected to the output end of the active power factor correction circuit module, and the negative electrode of the first polarized capacitor is grounded.

[0016] In one embodiment, the drive circuit further includes a second polarized capacitor. The positive electrode of the second polarized capacitor is connected to the output end of the power conversion isolation module, and the negative electrode of the second polarized capacitor is grounded.

[0017] In one embodiment, the power conversion isolation module further includes a power conversion transformer. The power supply end of the power conversion transformer is connected to the output end of the active power factor correction circuit module, and the output end of the power conversion transformer is connected to the constant voltage LED strip.

[0018] A dimming lighting fixture includes the DALI-based self-recovery short-circuit protection circuit according to any one of the above.

[0019] Compared with the prior art, the present disclosure has at least the following advantages:

[0020] 1. For the above DALI-based self-recovery short-circuit protection circuit, since a short-circuit detection circuit is added between the output end of the drive circuit and the first electronic switch tube, when a short circuit occurs in the drive circuit, the sharply increased current caused by the short circuit flows through the short-circuit detection circuit, pulling the voltage of the short-circuit signal receiving end in the DALI control circuit to a low level, and enabling the MCU to turn off the first electronic switch tube by using the interrupt function, thus avoiding the problem that the control circuit cannot quickly detect the abnormality at the output end, resulting in the breakdown of the first electronic switch tube Q1, and further improving the reliability of the DALI-based self-recovery short-circuit protection circuit.

[0021] 2. On the other hand, since the MCU in the DALI control circuit can set the interval time through software, cycle-detect the state of the short-circuit signal, and automatically resume the normal working state after the short-circuit fault is eliminated, the intelligence level of the DALI-based self-recovery short-circuit protection circuit is improved, and further enables the DALI-based self-recovery short-circuit protection circuit 10 to meet more intelligent application scenarios.

[0022] 3. The DALI-based self-recovery short-circuit protection circuit meets the requirements of the DALI protocol. At the same time, it can protect the first electronic switch tube from being damaged after a short circuit occurs in the circuit, and the DALI-based self-recovery short-circuit protection circuit can resume normal operation on its own after the short-circuit fault is eliminated, thereby improving the compatibility and practicability of the DALI-based self-recovery short-circuit protection circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present disclosure, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0024] Figure 1 FIG. is a schematic structural diagram of a DALI-based self-recovery short-circuit protection circuit according to an embodiment;

[0025] Figure 2 is Figure 1 the circuit diagram of the DALI-based self-recovery short-circuit protection circuit shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] In order to facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present disclosure are shown in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present disclosure more thorough and comprehensive.

[0027] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only embodiment.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art belonging to the technical field of the present disclosure. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0029] To better understand the technical solutions and beneficial effects of the present disclosure, the following further elaborates on the present disclosure in conjunction with specific embodiments:

[0030] As Figures 1 to 2 shown, the DALI-based self-recovery short-circuit protection circuit 10 according to an embodiment of the present disclosure includes a driving circuit 100, a short-circuit detection circuit 200, a DALI control circuit 300, and a constant-voltage light strip 400. The driving circuit 100 is used to supply power to the constant-voltage light strip 400.

[0031] Furthermore, the DALI-based self-recovery short-circuit protection circuit 10 further includes a detection resistor R4 and a first electronic switch tube Q1. The first end of the detection resistor R4 is connected to the output end of the driving circuit 100. The second end of the detection resistor R4 is connected to the short-circuit detection end AD1 of the short-circuit detection circuit 200. The second end of the detection resistor R4 is also connected to the first end of the first electronic switch tube Q1. The second end of the first electronic switch tube Q1 is connected to the constant-voltage light strip 400. The control end of the first electronic switch tube Q1 is connected to the PWM output end of the DALI control circuit 300. The short-circuit detection circuit 200 is connected to the short-circuit signal receiving end SD of the DALI control circuit 300.

[0032] Even further, the short-circuit detection circuit 200 includes a first resistor R1, a second resistor R2, a third resistor R3, and a second electronic switch tube Q2. The first end of the first resistor R1 is connected to the second end of the detection resistor R4. The second end of the first resistor R1 is respectively connected to the first end of the second resistor R2 and the control end of the second electronic switch tube Q2. The second end of the second resistor R2 and the second end of the second electronic switch tube Q2 are both connected to the ground end. The first end of the second electronic switch tube Q2 is respectively connected to the first end of the third resistor R3 and the short-circuit signal receiving end SD of the DALI control circuit 300. The second end of the third resistor R3 is used to be connected to an external power supply end.

[0033] In this embodiment, in the normal state, the driving circuit 100 outputs stable direct current to the detection resistor R4 and the first electronic switch tube Q1, and the external power supply supplies power to the short-circuit detection circuit 200 and the DALI control circuit 300. Since the two ends of the third resistor R3 are respectively connected to the external power supply end and the short-circuit signal receiving end SD of the DALI control circuit 300, the short-circuit signal receiving end SD of the DALI control circuit 300 obtains a high-level signal, and the circuit is in a normal working state. At the same time, the PWM output end of the DALI control circuit 300 outputs a high-level signal to the control end of the first electronic switch tube Q1, so that the first electronic switch tube Q1 is in a conducting state. After the stable direct current output by the driving circuit 100 passes through the detection resistor R4 and the first electronic switch tube Q1, it is conducted to the constant-voltage light strip 400, and further the constant-voltage light strip 400 is lit and the constant-light dimming function is realized.

[0034] Specifically, when a short circuit occurs at the output terminal of the driving circuit 100, the current in the circuit will increase sharply, and the current flowing through the detection resistor R4 will also increase. Since the first end of the first resistor R1 in the short-circuit detection circuit 200 is connected to the second end of the detection resistor R4, the sharply increased current will cause the voltage of the first resistor R1 to rise, causing the control terminal connection voltage of the second electronic switch tube Q2 connected to the second end of the first resistor R1 to rise; when the control terminal voltage of the second electronic switch tube Q2 is greater than its threshold voltage, the second electronic switch tube Q2 will be in the conducting state, causing the third resistor R3 to be grounded through the second electronic switch tube Q2, and the voltage of the short-circuit signal receiving terminal SD of the DALI control circuit 300 connected to the second end of the third resistor R3 is pulled to a low level, so that the DALI control circuit 300 detects the short-circuit state.

[0035] Further, after the DALI control circuit 300 detects the short-circuit state, the MCU in the DALI control circuit 300 uses the interrupt function to control the PWM output terminal of the DALI control circuit 300 to quickly terminate the output of the PWM signal, causing the control terminal of the first electronic switch tube Q1 to lose the high-level signal and making the first electronic switch tube Q1 in the cut-off state, thus avoiding damage to the first electronic switch tube Q1 caused by the short-circuit current and ensuring that the sharply increased current will not damage the constant-voltage light strip 400; at the same time, the MCU in the DALI control circuit 300 can set the interval time through software to cyclically detect the voltage signal of the short-circuit signal receiving terminal SD. If the short-circuit state is eliminated, that is, the short-circuit signal receiving terminal SD resumes the high-level signal, the PWM output terminal of the DALI control circuit 300 will automatically resume outputting the PWM signal, and then the circuit will return to the normal dimming state.

[0036] The above DALI-based self-recovery short-circuit protection circuit 10, due to the addition of a short-circuit detection circuit 200 between the output terminal of the drive circuit 100 and the first electronic switch tube Q1. When the drive circuit 100 has a short circuit, the sharply increased current caused by the short circuit flows through the short-circuit detection circuit 200, pulling the voltage of the short-circuit signal receiving terminal SD in the DALI control circuit 300 to a low level, and enabling the MCU to turn off the first electronic switch tube Q1 using the interrupt function, thus avoiding the problem that the control circuit cannot quickly detect the abnormality at the output terminal, resulting in the breakdown of the first electronic switch tube Q1, and further improving the reliability of the DALI-based self-recovery short-circuit protection circuit 10. On the other hand, since the MCU in the DALI control circuit 300 can set the interval time through software, cycle detect the state of the short-circuit signal, and automatically resume the normal working state after the short-circuit fault is eliminated, it improves the intelligence level of the DALI-based self-recovery short-circuit protection circuit 10, and further enables the DALI-based self-recovery short-circuit protection circuit 10 to meet more intelligent application scenarios. The DALI-based self-recovery short-circuit protection circuit 10 meets the requirements of the DALI protocol, can protect the first electronic switch tube Q1 from being damaged after a short circuit in the circuit, and the DALI-based self-recovery short-circuit protection circuit 10 can automatically resume normal operation after the short-circuit fault is eliminated, thereby improving the compatibility and practicality of the DALI-based self-recovery short-circuit protection circuit 10.

[0037] As Figure 2 shown, in one embodiment, the short-circuit detection circuit 200 further includes a first capacitor C3. The first end of the first capacitor C3 is connected to the short-circuit signal receiving terminal SD of the DALI control circuit 300, and the second end of the first capacitor C3 is grounded. In this embodiment, since the capacitor has the functions of storing electric energy and filtering, it can absorb or release energy when the voltage of the short-circuit detection circuit 200 fluctuates, enabling the first capacitor C3 to reduce the influence brought by the voltage fluctuation in the short-circuit detection circuit 200, thereby ensuring that the short-circuit signal receiving terminal SD of the DALI control circuit 300 can obtain a stable voltage signal.

[0038] As Figure 2As shown, in one embodiment, the first electronic switch Q1 is an N-channel MOS transistor. The drain of the first electronic switch Q1 is connected to the second end of the detection resistor R4. The source of the first electronic switch Q1 is connected to the constant voltage strip 400. The gate of the first electronic switch Q1 is connected to the PWM output terminal of the DALI control circuit 300. In this embodiment, since the first electronic switch Q1 is an N-channel MOS transistor, when the PWM output terminal of the DALI control circuit 300 outputs a high-level signal to the gate of the first electronic switch Q1, the gate voltage is greater than its threshold voltage, so that the first electronic switch Q1 is turned on. The current output by the driving circuit 100 is conducted to the constant voltage strip 400 after passing through the first electronic switch Q1, and the constant voltage strip 400 is lit. When the PWM output terminal of the DALI control circuit 300 outputs a low-level signal to the gate of the first electronic switch Q1, the gate voltage is less than its threshold voltage, so that the first electronic switch Q1 is in the cut-off state. The current output by the driving circuit 100 cannot be conducted to the constant voltage strip 400 after passing through the first electronic switch Q1, and the constant voltage strip 400 is turned off. Furthermore, the DALI control circuit 300 can realize the constant voltage dimming function through the first electronic switch Q1.

[0039] As Figure 1 shown, in one embodiment, the driving circuit 100 includes a rectification module BD1. The input end of the rectification module BD1 is connected to the industrial frequency alternating current. The output end of the rectification module BD1 is connected to the constant voltage strip 400. In this embodiment, the rectification module BD1 includes a bridge rectification circuit. Since the input end of the rectification module BD1 is connected to the industrial frequency alternating current, after the industrial frequency alternating current passes through the bridge rectification circuit, a stable direct current voltage is output to the output end of the rectification module BD1, so that the direct current energy can be stably conducted to the constant voltage strip 400, and further ensure that the constant voltage strip 400 can work stably.

[0040] As Figure 1As shown, in one embodiment, the drive circuit 100 further includes an active power factor correction circuit module. The input end of the active power factor correction circuit module is connected to the output end of the rectification module BD1, and the output end of the active power factor correction circuit module is connected to the constant voltage strip 400. In this embodiment, since the active power factor correction circuit module can shape the input current by controlling the on and off of the switching device, when the input voltage changes, the active power factor correction circuit module can quickly adjust the working state of the switching device so that the input current is always in phase with the input voltage; after the industrial frequency alternating current passes through the bridge rectifier circuit of the rectification module BD1, the output current enters the active power factor correction circuit module, and the active power factor correction circuit module reshapes the input current to make it in phase with the input voltage, thereby improving the power factor and further improving the power utilization rate of the DALI-based self-recovery short-circuit protection circuit 10.

[0041] As Figure 1 shown, in one embodiment, the drive circuit 100 further includes a power conversion isolation module. The input end of the power conversion isolation module is connected to the output end of the active power factor correction circuit module, and the output end of the power conversion isolation module is connected to the constant voltage strip 400. In this embodiment, since the power conversion isolation module adopts an isolation design, it can effectively isolate the output end of the active power factor correction circuit module from the input end of the power conversion isolation module. Thus, through the isolation design and short-circuit detection function, the power conversion isolation module can effectively prevent the drive circuit 100 from affecting the constant voltage strip 400 after an abnormal state occurs, and further improve the stability of the DALI-based self-recovery short-circuit protection circuit 10.

[0042] As Figure 2 shown, in one embodiment, the drive circuit 100 further includes a first polarized capacitor C1. The positive electrode of the first polarized capacitor C1 is connected to the output end of the active power factor correction circuit module, and the negative electrode of the first polarized capacitor C1 is grounded. In this embodiment, since the first polarized capacitor C1 in the DC circuit can play a role in maintaining a stable voltage in the circuit, when the voltage output from the output end of the active power factor correction circuit module fluctuates, the first polarized capacitor C1 can store or release charges to offset the voltage fluctuation, thereby maintaining the voltage stability in the circuit and protecting the components in the circuit from damage.

[0043] As Figure 2As shown, in one embodiment, the drive circuit 100 further includes a second polarized capacitor C2. The positive electrode of the second polarized capacitor C2 is connected to the output terminal of the power conversion isolation module, and the negative electrode of the second polarized capacitor C2 is grounded. In this embodiment, since the second polarized capacitor C2 in the circuit can maintain a stable voltage in the circuit, when the voltage output from the output terminal of the power conversion isolation module fluctuates, the second polarized capacitor C2 can store or release charges, thereby canceling out the voltage fluctuations, and then maintaining the voltage stability in the circuit and protecting the components in the circuit from damage.

[0044] As Figure 2 shown, in one embodiment, the power conversion isolation module further includes a power conversion transformer T1A. The power supply terminal of the power conversion transformer T1A is connected to the output terminal of the active power factor correction circuit module, and the output terminal of the power conversion transformer T1A is connected to the constant voltage strip 400. In this embodiment, since the rectification module BD1 is connected to the power supply output terminal of the industrial frequency alternating current, and the DC voltage output by the rectification module BD1 is greater than the working voltage of the constant voltage strip 400, after the active power factor correction circuit module improves the power factor of the voltage output by the rectification module BD1, the voltage is output to the power conversion transformer T1A, and the power conversion transformer T1A then converts the output voltage into a voltage suitable for the normal operation of the constant voltage strip 400, so as to ensure that the constant voltage strip 400 can work stably.

[0045] A dimming lighting fixture includes the DALI-based self-recovery short-circuit protection circuit 10 of any one of the above. In this embodiment, in the normal state, the drive circuit 100 outputs stable direct current to the detection resistor R4 and the first electronic switch tube Q1, and the external power supply supplies power to the short-circuit detection circuit 200 and the DALI control circuit 300. Since both ends of the third resistor R3 are respectively connected to the power supply terminal of the external power supply and the short-circuit signal receiving terminal SD of the DALI control circuit 300, the short-circuit signal receiving terminal SD of the DALI control circuit 300 obtains a high-level signal, and the circuit is in a normal working state. At the same time, the PWM output terminal of the DALI control circuit 300 outputs a high-level signal to the control terminal of the first electronic switch tube Q1, so that the first electronic switch tube Q1 is in a conducting state. After the stable direct current output by the drive circuit 100 passes through the detection resistor R4 and the first electronic switch tube Q1, it is conducted to the constant-voltage light strip 400, so that the constant-voltage light strip 400 is lit and the constant-light dimming function is realized. Specifically, when a short circuit occurs at the output terminal of the drive circuit 100, the current in the circuit will increase sharply, and the current flowing through the detection resistor R4 will also increase. Since the first end of the first resistor R1 in the short-circuit detection circuit 200 is connected to the second end of the detection resistor R4, the sharply increased current will cause the voltage of the first resistor R1 to rise, so that the connection voltage of the control terminal of the second electronic switch tube Q2 connected to the second end of the first resistor R1 rises; when the control terminal voltage of the second electronic switch tube Q2 is greater than its threshold voltage, the second electronic switch tube Q2 will be in a conducting state, so that the third resistor R3 is grounded through the second electronic switch tube Q2, and the voltage of the short-circuit signal receiving terminal SD of the DALI control circuit 300 connected to the second end of the third resistor R3 is pulled to a low level, so that the DALI control circuit 300 detects a short-circuit state. Further, after the DALI control circuit 300 detects a short-circuit state, the MCU in the DALI control circuit 300 uses the interrupt function to control the PWM output terminal of the DALI control circuit 300 to quickly terminate the output of the PWM signal, so that the control terminal of the first electronic switch tube Q1 loses the high-level signal and makes the first electronic switch tube Q1 in a cut-off state, thereby avoiding damage to the first electronic switch tube Q1 caused by the short-circuit current and ensuring that the sharply increased current does not damage the constant-voltage light strip 400; at the same time, the MCU in the DALI control circuit 300 can set the interval time through software to cyclically detect the voltage signal of the short-circuit signal receiving terminal SD. If the short-circuit state is eliminated, that is, the short-circuit signal receiving terminal SD resumes the high-level signal, the PWM output terminal of the DALI control circuit 300 will automatically resume outputting the PWM signal, so that the circuit resumes the normal dimming state.

[0046] Compared with the prior art, the present disclosure has at least the following advantages:

[0047] 1. For the above DALI-based self-recovery short-circuit protection circuit 10, since a short-circuit detection circuit 200 is added between the output terminal of the drive circuit 100 and the first electronic switch tube Q1, when a short circuit occurs in the drive circuit 100, the sharply increased current caused by the short circuit flows through the short-circuit detection circuit 200, pulling the voltage of the short-circuit signal receiving terminal SD in the DALI control circuit 300 to a low level, and enabling the MCU to turn off the first electronic switch tube Q1 using the interrupt function, thus avoiding the problem that the control circuit cannot quickly detect an abnormality at the output terminal, resulting in the breakdown of the first electronic switch tube Q1, and further improving the reliability of the DALI-based self-recovery short-circuit protection circuit 10.

[0048] 2. On the other hand, since the MCU in the DALI control circuit 300 can set the interval time through software, cycle-detect the state of the short-circuit signal, and automatically resume the normal working state after the short-circuit fault is eliminated, the intelligence level of the DALI-based self-recovery short-circuit protection circuit 10 is improved, and thus the DALI-based self-recovery short-circuit protection circuit 10 can meet more intelligent application scenarios.

[0049] 3. The DALI-based self-recovery short-circuit protection circuit 10 meets the requirements of the DALI protocol, can protect the first electronic switch tube Q1 from being damaged when a short circuit occurs in the circuit, and the DALI-based self-recovery short-circuit protection circuit 10 can automatically resume normal operation after the short-circuit fault is eliminated, thereby improving the compatibility and practicality of the DALI-based self-recovery short-circuit protection circuit 10.

[0050] The above embodiments merely represent several implementation manners of the present disclosure, and their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the disclosed patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several modifications and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A DALI-based self-recovery short-circuit protection circuit, characterized in that It includes a driving circuit, a short-circuit detection circuit, a DALI control circuit and a constant-voltage light strip, and the driving circuit is used to supply power to the constant-voltage light strip; The DALI-based self-recovery short-circuit protection circuit further includes a detection resistor and a first electronic switch tube. The first end of the detection resistor is connected to the output end of the driving circuit, the second end of the detection resistor is connected to the short-circuit detection end of the short-circuit detection circuit, the second end of the detection resistor is also connected to the first end of the first electronic switch tube, the second end of the first electronic switch tube is connected to the constant-voltage light strip, the control end of the first electronic switch tube is connected to the PWM output end of the DALI control circuit, and the short-circuit detection circuit is connected to the short-circuit signal receiving end of the DALI control circuit; The short-circuit detection circuit includes a first resistor, a second resistor, a third resistor and a second electronic switch tube. The first end of the first resistor is connected to the second end of the detection resistor, the second end of the first resistor is respectively connected to the first end of the second resistor and the control end of the second electronic switch tube, the second end of the second resistor and the second end of the second electronic switch tube are both connected to the ground terminal, the first end of the second electronic switch tube is respectively connected to the first end of the third resistor and the short-circuit signal receiving end of the DALI control circuit, and the second end of the third resistor is used to be connected to an external power supply terminal.

2. The self - recovery short - circuit protection circuit based on DALI according to claim 1, wherein, The short-circuit detection circuit further includes a first capacitor. The first end of the first capacitor is connected to the short-circuit signal receiving end of the DALI control circuit, and the second end of the first capacitor is grounded.

3. The self - recovery short - circuit protection circuit based on DALI according to claim 1, characterized in that, The first electronic switch tube is an N-channel MOS tube. The drain of the first electronic switch tube is connected to the second end of the detection resistor, the source of the first electronic switch tube is connected to the constant-voltage light strip, and the gate of the first electronic switch tube is connected to the PWM output end of the DALI control circuit.

4. The DALI-based self-recovery short-circuit protection circuit according to claim 1, wherein The driving circuit includes a rectification module. The input end of the rectification module is connected to industrial-frequency alternating current, and the output end of the rectification module is connected to the constant-voltage light strip.

5. The self - recovery short - circuit protection circuit based on DALI according to claim 4, characterized in that, The driving circuit further includes an active power factor correction circuit module. The input end of the active power factor correction circuit module is connected to the output end of the rectification module, and the output end of the active power factor correction circuit module is connected to the constant-voltage light strip.

6. The DALI-based self-recovery short-circuit protection circuit according to claim 5, characterized in that, The driving circuit further includes a power conversion isolation module. The input end of the power conversion isolation module is connected to the output end of the active power factor correction circuit module, and the output end of the power conversion isolation module is connected to the constant-voltage light strip.

7. The DALI-based self-recovery short-circuit protection circuit according to claim 5, characterized in that, The driving circuit further includes a first polarized capacitor. The positive pole of the first polarized capacitor is connected to the output end of the active power factor correction circuit module, and the negative pole of the first polarized capacitor is grounded.

8. The DALI-based self-recovery short-circuit protection circuit according to claim 6, wherein, The driving circuit further includes a second polarized capacitor. The positive pole of the second polarized capacitor is connected to the output end of the power conversion isolation module, and the negative pole of the second polarized capacitor is grounded.

9. The self - recovery short - circuit protection circuit based on DALI according to claim 6, characterized in that, The power conversion isolation module further includes a power conversion transformer. The power supply end of the power conversion transformer is connected to the output end of the active power factor correction circuit module, and the output end of the power conversion transformer is connected to the constant voltage light strip.

10. A dimmable lighting fixture, characterized in that, It includes the DALI-based self-recovery short-circuit protection circuit as described in claims 1 to 9 above.

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