LED drive circuit and lamp

Abstract

The utility model provides an LED drive circuit and a lamp. The LED driving circuit comprises a main power module, a control module and a voltage detection module, the input end of the main power module is connected with the power supply, the output end is connected with the LED, and the control end is connected with the output end of the control module; the input end of the voltage detection module detects the output voltage of the main power module, and the output end of the voltage detection module is connected with the enabling end of the control module and used for sending the detected output voltage of the main power module to the control module; wherein when the voltage of the enabling end of the control module is smaller than the preset voltage, the output end of the control module enables to output a high level; when the voltage of the enabling end of the control module is not smaller than the preset voltage, the output end of the control module normally outputs a PWM signal. The voltage detection module is arranged, when the output voltage of the LED is low, the control module outputs a high level all the time, large-current charging is conducted on the capacitor, the starting time of the LED is shortened, and overcharging is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of lamps, and in particular to an LED drive circuit and a lamp. Background Art

[0002] With the increasing shortage of energy and environmental problems, LED lamps have been widely used in the lighting field due to their energy saving and environmental protection. The dimming methods of LED lamps usually include analog dimming, thyristor dimming and pulse width (PWM) modulation. Among these three dimming methods, the most commonly used dimming technology is PWM dimming, which uses pulse width modulation signals to repeatedly switch LED lamps, adjust the average current of LEDs, and then adjust the brightness of LED lamps.

[0003] In the prior art, the output end of the LED driving circuit is usually provided with a large-capacity electrolytic capacitor. The electrolytic capacitor needs to be charged during startup, and the charging time is long, which results in a long startup time and affects the user experience. Utility Model Content

[0004] The embodiment of the utility model provides an LED driving circuit and a lamp to solve the problem of long startup time of LED lamps in the prior art.

[0005] In a first aspect, an embodiment of the utility model provides an LED driving circuit, comprising: a main power module, a control module and a voltage detection module; wherein a first capacitor is provided at the output end of the main power module;

[0006] The input end of the main power module is used to connect to the power supply, the output end of the main power module is used to connect to the LED, and the control end of the main power module is connected to the output end of the control module;

[0007] The input end of the voltage detection module detects the output voltage of the main power module, and the output end of the voltage detection module is connected to the enable end of the control module, so as to send the detected output voltage of the main power module to the control module;

[0008] Among them, when the voltage of the enable end of the control module is less than the preset voltage, the output end of the control module is enabled to output a high level; when the voltage of the enable end of the control module is not less than the preset voltage, the output end of the control module normally outputs a PWM signal.

[0009] Optionally, the main power module includes: an input rectifier filter unit, a power unit, an isolation transformer, an output rectifier filter unit and an auxiliary output rectifier filter unit; the isolation transformer includes: a primary winding, a secondary winding and an auxiliary winding, and the auxiliary winding is coupled with the secondary winding; wherein the first capacitor is arranged at the output end of the output rectifier filter unit; and the output end of the auxiliary output rectifier filter unit is provided with a second capacitor;

[0010] The input end of the input rectifying and filtering unit is connected to the input end of the main power module, and the output end of the input rectifying and filtering unit is connected to the input end of the power unit;

[0011] The control end of the power unit is connected to the control end of the main power module, and the output end of the power unit is connected to the primary winding;

[0012] The input end of the output rectifying and filtering unit is connected to the secondary winding, and the output end of the output rectifying and filtering unit is connected to the output end of the main power module;

[0013] The input end of the auxiliary output rectifying and filtering unit is connected to the auxiliary winding, and the output end of the auxiliary output rectifying and filtering unit is connected to the input end of the voltage detection module.

[0014] Optionally, the output rectification and filtering unit further includes: a first diode and a third capacitor;

[0015] The anode of the first diode is connected to the first end of the secondary winding, and the cathode of the first diode is connected to the first end of the first capacitor and the output end of the output rectifying and filtering unit respectively;

[0016] The second end of the first capacitor is respectively connected to the second end of the secondary winding, the first end of the third capacitor and the first grounding end;

[0017] The second end of the third capacitor is connected to the second ground end;

[0018] Wherein, the first ground terminal is connected to the cathode of the LED.

[0019] Optionally, the auxiliary output rectifying and filtering unit further includes: a second diode and a fourth capacitor;

[0020] The anode of the second diode is connected to the first end of the auxiliary winding, and the cathode of the second diode is connected to the first end of the second capacitor and the output end of the auxiliary output rectifying and filtering unit respectively;

[0021] The second end of the second capacitor is respectively connected to the second end of the auxiliary winding, the first end of the fourth capacitor and the third grounding end;

[0022] The second terminal of the fourth capacitor is connected to the second ground terminal.

[0023] Optionally, the voltage detection module includes: a first resistor and a second resistor;

[0024] The first end of the first resistor is connected to the input end of the voltage detection module, and the second end of the first resistor is connected to the first end of the second resistor and the output end of the voltage detection module respectively;

[0025] The second end of the second resistor is connected to the third ground end.

[0026] Optionally, the control module includes: a control unit and an isolation output unit;

[0027] The enable terminal of the control unit is connected to the enable terminal of the control module, and the output terminal of the control unit is connected to the input terminal of the isolation output unit;

[0028] The output end of the isolation output unit is connected to the output end of the control module;

[0029] Wherein, the output end of the isolation output unit is grounded and isolated from the input end of the isolation output unit;

[0030] The input rectifier filter unit and the power unit are both connected to the second ground terminal;

[0031] The input end of the isolation output unit, the control unit and the voltage detection module are all connected to the third grounding end.

[0032] Optionally, the isolation output unit includes: an optical coupler, a third resistor and a fourth resistor;

[0033] The positive input terminal of the optical coupler is connected to the input terminal of the isolation output unit through the third resistor, and the negative input terminal of the optical coupler is connected to the third ground terminal;

[0034] The positive output terminal of the optical coupler is connected to the DC power supply through the fourth resistor, and the negative output terminal of the optical coupler is connected to the output terminal of the isolation output unit.

[0035] Optionally, the main power module further includes: a DCDC unit;

[0036] The input end of the DCDC unit is respectively connected to the output end of the auxiliary output rectifying and filtering unit and the input end of the voltage detection module, and the output end of the DCDC unit is connected to the power supply end of the control module.

[0037] Optionally, the LED driving circuit further includes: a dimming module;

[0038] The input end of the dimming module is used to receive the dimming signal sent by the user, and the output end of the dimming module is connected to the dimming control end of the control module to send the dimming signal to the control module.

[0039] In a second aspect, an embodiment of the utility model provides a lamp, comprising: an LED and an LED driving circuit provided by any one of the above embodiments;

[0040] The LED driving circuit is used to drive the LED.

[0041] The embodiment of the utility model provides an LED driving circuit and a lamp, wherein the LED driving circuit comprises: a main power module, a control module and a voltage detection module; wherein the output end of the main power module is provided with a first capacitor; the input end of the main power module is used to connect to a power source, the output end of the main power module is used to connect to an LED, and the control end of the main power module is connected to the output end of the control module; the input end of the voltage detection module detects the output voltage of the main power module, and the output end of the voltage detection module is connected to the enable end of the control module, and is used to send the detected output voltage of the main power module to the control module; wherein, when the voltage of the enable end of the control module is less than a preset voltage, the output end of the control module is enabled to output a high level; when the voltage of the enable end of the control module is not less than a preset voltage, the output end of the control module normally outputs a PWM signal. When the lamp is started, the voltage at the output end of the main power module will gradually rise, and when the preset voltage is reached, it indicates that the capacitor is fully charged. Based on this, in the implementation of the utility model, the LED driving circuit is provided with a voltage detection module to detect the voltage at the output end of the main power module. When the voltage is small, it indicates that the capacitor is being charged. The control module enables continuous output of a high level, and the main power module quickly charges the capacitor at maximum power output, thereby shortening the charging time. When the voltage at the output end of the main power module reaches a certain voltage value, it indicates that the capacitor is fully charged, and the control module resumes normal operation and outputs a PWM signal normally, thereby controlling the main power module to work normally and drive the LED to emit light, thereby greatly improving the charging speed of the capacitor without causing overcharging, reducing the startup time of the lamp, and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0043] Figure 1 This is a circuit structure diagram of an LED driving circuit provided by an embodiment of the utility model;

[0044] Figure 2 This is a schematic diagram of the circuit structure of a main power module provided by an embodiment of the utility model;

[0045] Figure 3 This is a schematic diagram of a partial circuit principle of an LED driving circuit provided by an embodiment of the utility model;

[0046] Figure 4 It is a schematic diagram of the circuit principle of an output rectifying and filtering unit and an auxiliary output rectifying and filtering unit provided by an embodiment of the utility model;

[0047] Figure 5 This is a partial circuit principle diagram of another LED driving circuit provided by an embodiment of the utility model;

[0048] Figure 6 This is a partial circuit principle diagram of another LED driving circuit provided by an embodiment of the utility model;

[0049] Figure 7 This is a circuit structure diagram of another LED driving circuit provided by an embodiment of the utility model;

[0050] Figure 8 This is a circuit structure diagram of another LED driving circuit provided by an embodiment of the utility model;

[0051] Fig. 9 This is a circuit schematic diagram of a dimming module provided by an embodiment of the utility model;

[0052] Fig.10 It is a comparison diagram of the effects of the drive circuit after adopting the embodiment of the utility model and the prior art. DETAILED DESCRIPTION

[0053] In order to enable people in the technical field to better understand the present solution, the technical solution in the embodiment of the present solution will be clearly described below in conjunction with the drawings in the embodiment of the present solution. Obviously, the described embodiment is an embodiment of a part of the present solution, not all of the embodiments. Based on the embodiments in the present solution, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present solution.

[0054] The term "including" and any other variations in the specification and claims of this solution and the above drawings mean "including but not limited to", and is intended to cover non-exclusive inclusions and is not limited to the examples listed in the text. In addition, the terms "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0055] The following is a detailed description of the implementation of the present invention in conjunction with the specific drawings:

[0056] Figure 1 This is a schematic diagram of the structure of an LED driving circuit provided by an embodiment of the utility model. Figure 1 The LED driving circuit includes: a main power module 11, a control module 12 and a voltage detection module 13; wherein a first capacitor C1 is provided at the output end of the main power module 11;

[0057] The input end of the main power module 11 is used to connect to the power supply, the output end of the main power module 11 is used to connect to the LED, and the control end of the main power module 11 is connected to the output end of the control module 12;

[0058] The input end of the voltage detection module 13 detects the output voltage of the main power module 11, and the output end of the voltage detection module 13 is connected to the enable end of the control module 12, so as to send the detected output voltage of the main power module 11 to the control module 12;

[0059] Among them, when the voltage of the enable end of the control module 12 is less than the preset voltage, the output end of the control module 12 is enabled to output a high level; when the voltage of the enable end of the control module 12 is not less than the preset voltage, the output end of the control module 12 normally outputs a PWM signal.

[0060] The main power module 11 drives the LED to emit light under the control of the control module 12; under normal conditions, the control module 12 sends a PWM signal with a preset duty cycle to the main power module 11, and uses pulse width modulation to adjust the output current, thereby adjusting the brightness of the LED. When the LED is started, the main power module 11 charges the first capacitor C1 with a preset current (related to the PWM duty cycle). Based on the characteristics of the capacitor, the voltage of the first capacitor C1 (that is, the output voltage of the main power module 11) gradually increases, and reaching the threshold voltage indicates that the charging is completed, and the LED starts to work normally. Since the capacity of the first capacitor C1 is large, the charging time is long, and the startup time is long.

[0061] Based on the above, the output voltage of the main power module 11 reflects the charging status of the first capacitor C1. Based on this, in the embodiment of the utility model, the output voltage of the main power module 11 is detected, and the control module 12 is enabled. When the output voltage of the main power module 11 is small, the control module 12 continuously outputs a high level, which is equivalent to a 100% duty cycle of the PWM model. The main power module 11 charges the first capacitor C1 with the maximum current to increase the startup speed of the lamp. When the voltage reaches the threshold voltage, the control module 12 normally outputs the PWM signal and resumes normal operation.

[0062] In the embodiment of the utility model, high current charging is performed when the voltage is low, which greatly reduces the startup time of the lamp; at the same time, normal PWM control is restored when the threshold voltage is reached, which can avoid overcharging caused by high current operation when the voltage of the first capacitor C1 is high, thereby improving the safety of the circuit and providing a good user experience.

[0063] It should be noted that the preset voltage corresponds to the threshold voltage across the first capacitor C1.

[0064] In one possible implementation, reference Figure 2The main power module 11 may include: an input rectifying and filtering unit 111, a power unit 112, an isolation transformer T, an output rectifying and filtering unit 113 and an auxiliary output rectifying and filtering unit 114; the isolation transformer T includes: a primary winding, a secondary winding and an auxiliary winding, and the auxiliary winding is coupled with the secondary winding; wherein the first capacitor C1 is arranged at the output end of the output rectifying and filtering unit 113; the output end of the auxiliary output rectifying and filtering unit 114 is provided with a second capacitor C2;

[0065] The input end of the input rectifying and filtering unit 111 is connected to the input end of the main power module 11, and the output end of the input rectifying and filtering unit 111 is connected to the input end of the power unit 112;

[0066] The control end of the power unit 112 is connected to the control end of the main power module 11, and the output end of the power unit 112 is connected to the primary winding;

[0067] The input end of the output rectifying and filtering unit 113 is connected to the secondary winding, and the output end of the output rectifying and filtering unit 113 is connected to the output end of the main power module 11;

[0068] An input end of the auxiliary output rectifying and filtering unit 114 is connected to the auxiliary winding, and an output end of the auxiliary output rectifying and filtering unit 114 is connected to an input end of the voltage detection module 13 .

[0069] In the embodiment of the utility model, in order to improve the safety of the lamp, an isolation transformer T is provided for isolation. At the same time, the isolation transformer T leads to an auxiliary winding, the auxiliary winding is coupled with the secondary winding, the voltage across the second capacitor C2 is linearly related to the voltage across the first capacitor C1, the voltage across the second capacitor C2 can directly reflect the voltage across the first capacitor C1, the voltage detection module 13 does not directly sample the voltage across the first capacitor C1, and indirectly detects the voltage across the first capacitor C1 by detecting the auxiliary winding, thereby further improving the safety of the lamp.

[0070] Specifically, the circuit structure of the input rectifier filter unit 111 and the power unit 112 can refer to Figure 3 The details will not be described in detail here, as they are all conventional technical means in this field.

[0071] In one possible implementation, reference Figure 4 , the output rectifying and filtering unit 113 may further include: a first diode D1 and a third capacitor C3;

[0072] The anode of the first diode D1 is connected to the first end of the secondary winding, and the cathode of the first diode D1 is connected to the first end of the first capacitor C1 and the output end of the output rectifying and filtering unit 113 respectively;

[0073] The second end of the first capacitor C1 is respectively connected to the second end of the secondary winding, the first end of the third capacitor C3 and the first ground end;

[0074] A second terminal of the third capacitor C3 is connected to the second ground terminal;

[0075] Wherein, the first ground terminal is connected to the cathode of the LED.

[0076] The first diode D1 is used to prevent backflow, and the second capacitor C2 is used for ground isolation.

[0077] In one possible implementation, reference Figure 4 , the auxiliary output rectifying and filtering unit 114 may further include: a second diode D2 and a fourth capacitor C4;

[0078] The anode of the second diode D2 is connected to the first end of the auxiliary winding, and the cathode of the second diode D2 is connected to the first end of the second capacitor C2 and the output end of the auxiliary output rectifying and filtering unit 114 respectively;

[0079] The second end of the second capacitor C2 is respectively connected to the second end of the auxiliary winding, the first end of the fourth capacitor C4 and the third ground end;

[0080] A second terminal of the fourth capacitor C4 is connected to the second ground terminal.

[0081] As above, the second diode D2 is used to prevent backflow, and the fourth capacitor C4 is used for ground isolation; the output rectification and filtering unit 113 and the auxiliary output rectification and filtering unit 114 have the same circuit structure, so that the voltage across the second capacitor C2 can more accurately reflect the voltage across the first capacitor C1.

[0082] Furthermore, the number of turns of the secondary winding and the number of turns of the auxiliary winding may be the same.

[0083] For further reference, Figure 5 The first diode D1 can also be connected in parallel with a discharge circuit, and the second diode D2 can also be connected in series with a current-limiting resistor, which is not limited to Figure 4 The circuit structure can be adjusted according to the actual application requirements. For details, refer to Figure 5 , I will not go into details here.

[0084] In one possible implementation, reference Figure 6 , the voltage detection module 13 includes: a first resistor R1 and a second resistor R2;

[0085] The first end of the first resistor R1 is connected to the input end of the voltage detection module 13, and the second end of the first resistor R1 is connected to the first end of the second resistor R2 and the output end of the voltage detection module 13 respectively;

[0086] The second end of the second resistor R2 is connected to the third ground end.

[0087] In the embodiment of the present invention, resistor voltage division is adopted to meet the voltage requirement of the enable terminal of the control module 12 .

[0088] In one possible implementation, reference Figure 7 , the control module 12 may include: a control unit 121 and an isolation output unit 122;

[0089] The enable terminal of the control unit 121 is connected to the enable terminal of the control module 12, and the output terminal of the control unit 121 is connected to the input terminal of the isolation output unit 111;

[0090] The output end of the isolation output unit 122 is connected to the output end of the control module 12;

[0091] The output end of the isolation output unit 122 is grounded and isolated from the input end of the isolation output unit 122;

[0092] The input rectifying and filtering unit 111 and the power unit 112 are both connected to the second ground terminal;

[0093] The input end of the isolation output unit 122 , the control unit 121 , and the voltage detection module 13 are all connected to the third ground end.

[0094] To further improve the isolation of the circuit, the PWM signal generated by the control unit 121 is output to the power unit 112 via the isolation output unit 122, which further improves the safety of the circuit and enables the circuit to better meet safety regulations.

[0095] The circuit schematic diagram of the control unit 121 is shown in FIG. Figure 6 , which can be realized by using a single-chip microcomputer or other control chip that can output PWM signals, and the details will not be repeated here.

[0096] In one possible implementation, reference Figure 3 , the isolation output unit 132 may include: an optical coupler U1, a third resistor R3 and a fourth resistor R4;

[0097] The positive input terminal of the optical coupler U1 is connected to the input terminal of the isolation output unit 132 through the third resistor R3, and the negative input terminal of the optical coupler U1 is connected to the third ground terminal;

[0098] The positive output terminal of the optical coupler U1 is connected to the DC power supply through the fourth resistor R4 , and the negative output terminal of the optical coupler U1 is connected to the output terminal of the isolation output unit 132 .

[0099] Specifically, the isolation output unit 132 can be isolated by using an optical coupler U1, which has a simple circuit structure, low device cost, and good isolation effect. The front and rear ends of the optical coupler U1 are connected to different ground terminals for ground isolation.

[0100] In one possible implementation, reference Figure 8 , the main power module 11 may further include: a DCDC unit 115;

[0101] The input end of the DCDC unit 115 is respectively connected to the output end of the auxiliary output rectifying and filtering unit 114 and the input end of the voltage detection module 13 , and the output end of the DCDC unit 115 is connected to the power supply end of the control module 12 .

[0102] In the embodiment of the utility model, a DCDC unit 115 is provided to power the control module 12. The DCDC unit 115 is powered by an auxiliary winding and is isolated from the secondary winding, thereby isolating the control module 12 from the main power output end (secondary winding part) to improve safety.

[0103] Specifically, the circuit schematic diagram of the DCDC unit 115 is shown in FIG. Figure 5 , the details will not be repeated here.

[0104] In a possible implementation, the LED driving circuit may further include: a dimming module;

[0105] The input end of the dimming module is used to receive a dimming signal sent by a user, and the output end of the dimming module is connected to the dimming control end of the control module 12 for sending the dimming signal to the control module 12 .

[0106] The embodiment of the utility model is further provided with a dimming module for receiving a dimming signal sent by a user. The control module 12 adjusts the duty cycle of the PWM signal based on the dimming signal, thereby achieving adjustment of the LED brightness.

[0107] For details, please refer to the circuit of dimming module. Fig. 9 The dimming module can be powered by the DCDC unit 115, for details, refer to Fig. 9 and Figure 5 , I will not go into details here.

[0108] refer to Fig.10 , which shows a comparison diagram of the effects of the LED driving circuit provided by the embodiment of the utility model and the LED driving circuit in the prior art. It can be clearly seen that the startup time is significantly shortened.

[0109] Corresponding to the above embodiments, the utility model embodiment further provides a lamp, comprising: an LED and an LED driving circuit provided by any one of the above embodiments; the LED driving circuit is used to drive the LED. The lamp has the advantages of the above LED driving circuit, and the details are not repeated here.

[0110] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An LED driving circuit, characterized in that: include: A main power module, a control module and a voltage detection module; wherein a first capacitor is provided at the output end of the main power module; The input end of the main power module is used to connect to a power source, the output end of the main power module is used to connect to an LED, and the control end of the main power module is connected to the output end of the control module; The input end of the voltage detection module detects the output voltage of the main power module, and the output end of the voltage detection module is connected to the enable end of the control module, so as to send the detected output voltage of the main power module to the control module; Among them, when the voltage of the enable end of the control module is less than the preset voltage, the output end of the control module is enabled to output a high level; when the voltage of the enable end of the control module is not less than the preset voltage, the output end of the control module normally outputs a PWM signal.

2. The LED driving circuit according to claim 1, characterized in that: The main power module includes: an input rectifier filter unit, a power unit, an isolation transformer, an output rectifier filter unit and an auxiliary output rectifier filter unit; the isolation transformer includes: a primary winding, a secondary winding and an auxiliary winding, and the auxiliary winding is coupled with the secondary winding; wherein the first capacitor is arranged at the output end of the output rectifier filter unit; the output end of the auxiliary output rectifier filter unit is provided with a second capacitor; The input end of the input rectifying and filtering unit is connected to the input end of the main power module, and the output end of the input rectifying and filtering unit is connected to the input end of the power unit; The control end of the power unit is connected to the control end of the main power module, and the output end of the power unit is connected to the primary winding; The input end of the output rectifying and filtering unit is connected to the secondary winding, and the output end of the output rectifying and filtering unit is connected to the output end of the main power module; The input end of the auxiliary output rectifying and filtering unit is connected to the auxiliary winding, and the output end of the auxiliary output rectifying and filtering unit is connected to the input end of the voltage detection module.

3. The LED driving circuit according to claim 2, characterized in that: The output rectifying and filtering unit further includes: a first diode and a third capacitor; The anode of the first diode is connected to the first end of the secondary winding, and the cathode of the first diode is connected to the first end of the first capacitor and the output end of the output rectifying and filtering unit respectively; The second end of the first capacitor is respectively connected to the second end of the secondary winding, the first end of the third capacitor and the first ground end; The second end of the third capacitor is connected to the second ground end; Wherein, the first ground terminal is connected to the cathode of the LED.

4. The LED driving circuit according to claim 3, characterized in that: The auxiliary output rectifying and filtering unit further includes: a second diode and a fourth capacitor; The anode of the second diode is connected to the first end of the auxiliary winding, and the cathode of the second diode is connected to the first end of the second capacitor and the output end of the auxiliary output rectifying and filtering unit respectively; The second end of the second capacitor is respectively connected to the second end of the auxiliary winding, the first end of the fourth capacitor and the third ground end; The second end of the fourth capacitor is connected to the second ground end.

5. The LED driving circuit according to claim 4, characterized in that: The voltage detection module includes: a first resistor and a second resistor; The first end of the first resistor is connected to the input end of the voltage detection module, and the second end of the first resistor is connected to the first end of the second resistor and the output end of the voltage detection module respectively; The second end of the second resistor is connected to the third ground end.

6. The LED driving circuit according to claim 5, characterized in that: The control module includes: a control unit and an isolation output unit; The enable terminal of the control unit is connected to the enable terminal of the control module, and the output terminal of the control unit is connected to the input terminal of the isolation output unit; The output end of the isolation output unit is connected to the output end of the control module; Wherein, the output end of the isolation output unit is grounded and isolated from the input end of the isolation output unit; The input rectifier and filter unit and the power unit are both connected to the second ground terminal; The input end of the isolation output unit, the control unit and the voltage detection module are all connected to the third ground end.

7. The LED driving circuit according to claim 6, characterized in that: The isolation output unit includes: an optical coupler, a third resistor and a fourth resistor; The positive input terminal of the optical coupler is connected to the input terminal of the isolation output unit through the third resistor, and the negative input terminal of the optical coupler is connected to the third ground terminal; The positive output terminal of the optical coupler is connected to a DC power supply through the fourth resistor, and the negative output terminal of the optical coupler is connected to an output terminal of the isolation output unit.

8. The LED driving circuit according to any one of claims 2 to 7, characterized in that: The main power module also includes: a DCDC unit; The input end of the DCDC unit is respectively connected to the output end of the auxiliary output rectifying and filtering unit and the input end of the voltage detection module, and the output end of the DCDC unit is connected to the power supply end of the control module.

9. The LED driving circuit according to any one of claims 1 to 7, characterized in that: Also includes: Dimming module; The input end of the dimming module is used to receive a dimming signal sent by a user, and the output end of the dimming module is connected to the dimming control end of the control module to send the dimming signal to the control module.

10. A lamp, characterized in that: include: An LED and an LED driving circuit as claimed in any one of claims 1 to 9; The LED driving circuit is used to drive the LED.

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