Protection circuit, drive system, chip and circuit protection method, and drive method

Abstract

The present disclosure provides a protection circuit, a drive system, a chip and a circuit protection method, and a drive method. The protection circuit can be used in a circuit system in which a load is driven by a switch circuit, and acquire a voltage signal reflecting the voltage of a power supply bus on which the load located and generate a detection signal, and control the switch circuit to maintain a forcible non-conductive state within a protection period when detecting that the voltage of the detection signal satisfies a preset voltage warning condition. The present application solves the problem of circuit protection of DC-powered electronics in the prior art.

What is claimed is: 
     
         1 . A protection circuit, used in a circuit system in which a load is driven by a switch circuit, comprising:
 a detection unit, configured to acquire a voltage signal reflecting a power supply bus voltage from an electronics which is connected with the power supply bus, convert the voltage signal into a detection signal, detect the detection signal, and output corresponding detection result based on a preset voltage warning condition; and   a control unit, connected with an output terminal of the detection unit, and configured to control the switch circuit to maintain a forcible non-conductive state within a protection period when the received detection result indicates that the preset voltage warning condition is satisfied.   
     
     
         2 . The protection circuit of  claim 1 , wherein, the detection unit comprises:
 an acquisition module, connected with the power supply bus, and configured to acquire an instantaneous voltage signal of the power supply bus and output a detection signal corresponding to the instantaneous voltage signal; and   a detection module, configured to detect the detection signal and output corresponding detection result based on the preset voltage warning condition.   
     
     
         3 . The protection circuit of  claim 1 , wherein, the detection unit comprises:
 an acquisition module, connected with the switch circuit, and configured to acquire a detection signal reflecting a change of the power supply bus voltage from the switch circuit; and   a detection module, configured to detect the detection signal and output corresponding detection result based on the preset voltage warning condition.   
     
     
         4 . The protection circuit of  claim 3 , wherein, the acquisition module comprises a switch device, and a control terminal of the switch device is connected with the switch circuit, an output terminal of the switch device is connected with the detection module and is used to output the detection signal. 
     
     
         5 . The protection circuit of  claim 3 , wherein, the acquisition module comprises a high-pass filter, and one terminal of the high-pass filter is connected with the switch circuit, the other terminal of the high-pass filter is connected with the detection module and is used to output the detection signal. 
     
     
         6 . The protection circuit of  claim 1 , wherein, the detection unit comprises a comparator, and one input terminal of the comparator is used to receive the detection signal, the other input terminal of the comparator is used to receive an warning voltage threshold, and the comparator is configured to compare the voltage of the detection signal with the warning voltage threshold and output corresponding detection result. 
     
     
         7 . The protection circuit of  claim 1 , wherein, the preset voltage warning condition comprises an warning voltage threshold, the warning voltage threshold is preset based on the acquired voltage signal reflecting a power supply bus voltage. 
     
     
         8 . The protection circuit of  claim 1 , wherein, the control unit comprises:
 a delay control module, connected with the output terminal of the detection unit, and configured to output a first control signal when the received detection result indicates that the preset voltage warning condition is satisfied, start a delay timing based on the detection result output by the detection unit, and output a second control signal after the delay timing exceeds the protection period; and   a switch circuit control module, connected with an output terminal of the delay control module and the control terminal of the switch circuit, and configured to control the switch circuit to turn to and maintain the forcible non-conductive state based on the first control signal, and release from the forcible non-conductive state based on the second control signal.   
     
     
         9 . The protection circuit of  claim 8 , wherein, the delay control module is configured to start the delay timing when the received detection result indicates that the preset voltage warning condition is satisfied. 
     
     
         10 . The protection circuit of  claim 8 , wherein, the delay control module is configured to output the second control signal when the received detection result indicates that the preset voltage warning condition is not satisfied and the delay timing exceeds the protection period. 
     
     
         11 . The protection circuit of  claim 8 , wherein, the delay control module is configured to, during a period of delay timing, restart a delay timing based on the received detection result which indicates that the preset voltage warning condition is satisfied. 
     
     
         12 . The protection circuit of  claim 8 , wherein, the switch circuit control module comprises any of the following:
 a voltage regulator, connected with the control terminal of the switch circuit, and configured to regulate a voltage on the control terminal of the switch circuit based on the first control signal and the second control signal; and   a driver, connected with an input terminal of the switch circuit, and configured to control a drive unit of the switch circuit not to output a drive signal to the switch circuit when the first control signal is received, until the second control signal is received.   
     
     
         13 . The protection circuit of  claim 1 , wherein, an output terminal of the protection circuit is connected with a control terminal of a switch unit in the switch circuit, or the output terminal of the protection circuit is connected with an input terminal of a drive unit in the switch circuit, or the output terminal of the protection circuit is connected with a control terminal of the drive unit in the switch circuit. 
     
     
         14 . The protection circuit of  claim 1 , wherein, the circuit system is an LED drive system, and the load is LED load. 
     
     
         15 . A chip, comprising an output terminal which is connected with a switch circuit arranged on a power supply bus; and
 the protection circuit of  claim 1 , wherein, the protection circuit is configured to control the switch circuit to maintain a forcible non-conductive state within a protection period.   
     
     
         16 . A drive system, comprising:
 a rectifying circuit, configured to rectify an external AC voltage and output the rectified external AC voltage to a power supply bus on which a load is located;   a switch circuit, arranged on the power supply bus, and configured to control the power supply bus to be in a conductive state or non-conductive state;   a linear compensation circuit, configured to output a linear compensation signal to the switch circuit based on an acquired electric signal reflecting a power supply bus voltage, such that the switch circuit drives the load based on the linear compensation signal during a period in which the switch circuit is not in a forcible non-conductive state; and   the protection circuit of  claim 1 , connected with the switch circuit, and configured to control the switch circuit to maintain the forcible non-conductive state within a protection period.   
     
     
         17 . A method for protecting a circuit, used in a circuit system, and comprising the following steps:
 acquiring a voltage signal reflecting a voltage of a power supply bus to which the load is connected, and generating a detection signal based on the voltage signal reflecting the voltage of a power supply bus;   detecting the detection signal and obtaining corresponding detection result based on a preset voltage warning condition;   controlling the switch circuit to maintain a forcible non-conductive state within a protection period when the detection result indicates that the preset voltage warning condition is satisfied; and   not controlling the switch circuit to turn to the forcible non-conductive state when the detection result indicates that the preset voltage warning condition is not satisfied.   
     
     
         18 . The method for protecting a circuit of  claim 17 , wherein, the manner of acquiring a voltage signal reflecting a voltage of a power supply bus to which the load is connected, and generating a detection signal based on the voltage signal reflecting the voltage of a power supply bus comprises:
 acquiring an instantaneous voltage signal of the power supply bus and generating a detection signal corresponding to the instantaneous voltage signal.   
     
     
         19 . The method for protecting a circuit of  claim 17 , wherein, the manner of acquiring a voltage signal reflecting a voltage of a power supply bus to which the load is connected, and generating a detection signal based on the voltage signal reflecting the voltage of a power supply bus comprises:
 acquiring a detection signal reflecting a change of the power supply bus voltage from the switch circuit.   
     
     
         20 . The method for protecting a circuit of  claim 17 , wherein, the manner of detecting the detection signal and obtaining corresponding detection result based on a preset voltage warning condition comprises: comparing the voltage of the detection signal with the preset warning voltage threshold and outputting corresponding detection result. 
     
     
         21 . The method for protecting a circuit of  claim 17 , wherein, the manner of controlling the switch circuit to maintain a forcible non-conductive state within a protection period when the detection result indicates that a preset voltage warning condition is satisfied comprises:
 controlling the switch circuit to turn to and maintain the forcible non-conductive state when the detection result indicates that the preset voltage warning condition is satisfied; and   starting a delay timing, and releasing the switch circuit from the forcible non-conductive state after the delay timing exceeds the protection period.   
     
     
         22 . The method for protecting a circuit of  claim 19 , wherein, the step of starting a delay timing, and releasing the switch circuit from the forcible non-conductive state after the delay timing exceeds the protection period comprises: starting the delay timing when the received detection result indicates that the preset voltage warning condition is satisfied, and releasing the maintained forcible non-conductive state after the delay timing exceeds the protection period. 
     
     
         23 . The method for protecting a circuit of  claim 19 , wherein, the step of starting a delay timing and releasing the switch circuit from the forcible non-conductive state after the delay timing exceeds the protection period comprises: releasing the maintained forcible non-conductive state when the received detection result indicates that the preset voltage warning condition is not satisfied and the delay timing exceeds the protection period. 
     
     
         24 . The method for protecting a circuit of  claim 19 , wherein, the step of starting a delay timing and releasing the switch circuit from the forcible non-conductive state after the delay timing exceeds the protection period comprises: restarting a timing based on the received detection result which indicates that the preset voltage warning condition is satisfied, and releasing the maintained forcible non-conductive state after the restarted timing exceeds the protection period. 
     
     
         25 . A drive method, comprising:
 rectifying an received AC voltage;   outputting a linear compensation signal to a switch circuit which is arranged on a power supply bus based on an acquired electric signal reflecting a power supply bus voltage, such that the switch circuit is configured to drive a load based on the linear compensation signal during a period in which the switch circuit is not in a forcible non-conductive state; and   each step in the method for protecting a circuit of  claim 17 .