Driving circuit, driving controller and lamp

Abstract

The invention provides a driving circuit, a driving controller and a lamp, the driving circuit comprises a load module, an energy storage module, a constant current control module and a sampling signal module, and the load module comprises a first load and a second load which are connected with a power supply module; the energy storage module is connected with a first load, the power supply module charges the energy storage module, and the energy storage module can supply power to the load module; the constant current control module comprises a first control unit and a fourth control unit which are connected in parallel with a second load, and a second control unit and a third control unit which are connected in series with the second load. The sampling signal module comprises a diode D1 and a sampling module which are arranged between the power supply module and the energy storage module, and the sampling module samples the output voltage of the power supply module and controls connection or disconnection of the first control unit, the second control unit, the third control unit and the fourth control unit. According to the invention, the energy storage module and the constant current control module are arranged, so that the load can realize constant current output when the voltage fluctuation is relatively large, and the stroboflash of the lamp bead during the voltage fluctuation is avoided.

Description

Technical Field

[0001] The invention relates to a driving circuit, a driving controller and a lamp, and belongs to the technical field of driving circuits. Background Art

[0002] With the continuous development of the LED lighting industry, constant current control chips are required to have the characteristics of high integration, good circuit performance, and small size. At the same time, LED lighting performance indicators are also gradually improving, making the relevant certification requirements of linear constant current drive systems increasingly high. At present, high power factor linear constant current drive control systems have appeared on the market, which are mainly used to achieve constant current output of LEDs in AC power above 220V. However, for AC power below 220V, or AC power with a large fluctuation range, LEDs are still unable to achieve constant current output, causing LEDs to produce perceptible low-frequency ripple flicker in AC power below 220V. Long-term low-frequency ripple flicker can cause damage to human eyes. Figure 1 As shown, the traditional high PF flicker-free solution achieves LED constant current output by controlling the charge and discharge of the input capacitor E1. When the mains fluctuation decreases, the LED cannot achieve constant current output.

[0003] In view of this, it is indeed necessary to propose a driving circuit, a driving controller and a lamp to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a driving circuit, a driving controller and a lamp to solve the problem in the prior art that LEDs cannot achieve constant current output when the fluctuation of the mains power decreases.

[0005] To achieve the above object, the present invention provides a driving circuit connected to a power supply module, comprising:

[0006] A load module, comprising a first load and a second load connected in series, wherein the first load is connected to the power supply module;

[0007] an energy storage module connected to the input end of the first load, and charging the energy storage module when the power supply module outputs a high voltage, and supplying power to the load module from the energy storage module when the power supply module outputs a low voltage;

[0008] A constant current control module, comprising a first control unit and a fourth control unit connected in parallel with the second load, and a second control unit and a third control unit connected in series with the second load, to control the start or stop of the second load;

[0009] The sampling signal module includes a diode D1 and a sampling module. The diode D1 is arranged between the power supply module and the energy storage module. The sampling module is connected to the output end of the power supply module to sample the output voltage of the power supply module and control the connection or disconnection of the first control unit, the second control unit, the third control unit and the fourth control unit.

[0010] As a further improvement of the present invention, the energy storage module includes an energy storage capacitor C1, the constant current control module includes a resistor R3, one end of the resistor R3 is connected to the first control unit and the second control unit, and the other end is connected to the energy storage capacitor C1, and the other end of the energy storage capacitor C1 is connected to the first load to form a discharge circuit.

[0011] As a further improvement of the present invention, the energy storage module includes a diode D2, one end of the diode D2 is connected to the energy storage capacitor C1, and the other end is grounded to form a charging circuit for the energy storage capacitor C1.

[0012] As a further improvement of the present invention, the constant current control module includes a resistor R4, one end of the resistor R4 is connected to the third control unit and the fourth control unit, and the other end is grounded.

[0013] As a further improvement of the present invention, the sampling module includes a comparator, which samples the voltage of the power supply module and inputs the sampling result into the comparator to compare it with a fixed reference of the comparator. If the sampled voltage is not less than the fixed reference, the comparator outputs a first control signal to control the third control unit and the fourth control unit to be connected or disconnected.

[0014] As a further improvement of the present invention, the third control unit includes a third controller and a third transistor M3, one end of the third transistor M3 is connected to the third controller, the other end is connected to the output end of the second load, and the other end is grounded, the third controller receives the first control signal and compares it with the third reference of the third controller, if the first control signal is equal to the third reference, the third controller controls the third transistor M3 to be connected;

[0015] The fourth control unit includes a fourth controller and a fourth transistor M4, one end of the fourth transistor M4 is connected to the fourth controller, the other end is connected to the input end of the second load, and the other end is grounded. The fourth controller receives a first control signal and compares it with a fourth reference of the fourth controller. If the first control signal is equal to the fourth reference, the fourth controller controls the fourth transistor M4 to be connected.

[0016] As a further improvement of the present invention, the sampling module also includes a converter connected to the comparator. If the sampling voltage is less than a fixed reference, the comparator controls the converter to output a second control signal to control the first control unit and the second control unit to be connected or disconnected.

[0017] As a further improvement of the present invention, the second control unit includes a second controller and a second transistor M2, one end of the second transistor M2 is connected to the second controller, the other end is connected to the output end of the second load, and the other end is connected to the energy storage module, the second controller receives a second control signal and compares it with a second reference of the second controller, if the second control signal is equal to the second reference, the second controller controls the second transistor M2 to be connected;

[0018] The first control unit includes a first controller and a first transistor M1, one end of the first transistor M1 is connected to the first controller, the other end is connected to the input end of the second load, and the other end is connected to the energy storage module. The first controller receives a second control signal and compares it with a first reference of the first controller. If the second control signal is equal to the first reference, the first controller controls the first transistor M1 to be connected.

[0019] To achieve the above-mentioned purpose, the present invention provides a drive controller, including a power supply module and the aforementioned drive circuit, the power supply module converts the alternating current of the power grid into direct current to power the drive circuit, part of the drive circuit is arranged in a chip, the constant current control module is provided with a first control module including a first control unit and a second control unit, and a second control module including a third control unit and a fourth control unit, an isolation device is provided in the chip, the isolation device separates the first control module and the second control module, so that a discharge circuit is formed between the first control module and the energy storage module.

[0020] To achieve the above object, the present invention provides a lamp, comprising the above driving circuit.

[0021] The beneficial effects of the present invention are as follows: the driving circuit of the present invention, by setting an energy storage module and a constant current control module, enables the load to achieve constant current output when the voltage fluctuates greatly. It also has the characteristics of high input power factor, wide voltage, no flicker, and strong surge resistance, further avoiding the flicker of the lamp beads when the voltage fluctuates, thereby improving the protection of human eyes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a circuit diagram of a constant current driving solution in the prior art.

[0023] Figure 2is a circuit diagram of a driving circuit according to a preferred embodiment of the present invention.

[0024] Figure 3 4 is a circuit diagram of a drive controller according to a preferred embodiment of the present invention.

[0025] Figure 4 It is the waveform corresponding to the input voltage after the rectifier bridge and the positive electrode voltage of the energy storage capacitor in the present invention.

[0026] Figure 5 It is a current waveform diagram of the output current after the rectifier bridge, the charging and discharging current of the energy storage capacitor and the current of the LED light string in the present invention.

[0027] Figure 6 It is the corresponding waveform of the input voltage after the rectifier bridge, the positive electrode voltage of the energy storage capacitor and the current of the first light-emitting unit in the present invention.

[0028] Explanation of the accompanying drawings: drive controller 100, drive circuit 200, power supply module 1, chip 2, load module 7, first load 71, second load 72, energy storage module 3, energy storage capacitor C1, diode D2, constant current control module 4, first control module 41, first control unit 411, first controller 412, first transistor M1, second control unit 413, second controller 414, second transistor M2, resistor R3, second control module 42, third control unit 421, third controller 422, third transistor M3, fourth control unit 423, fourth controller 424, fourth transistor M4, resistor R4, sampling signal module 5, diode D1, sampling module 6, comparator 61, converter 62, resistor R1, resistor R2. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] See also Figure 2 As shown, the present invention discloses a driving circuit 200 for regulating and driving a load, so that the load can work stably when the voltage fluctuates greatly, and at the same time, it also has a high input power factor and a wide voltage input function.

[0031] The drive circuit 200 is connected to the power supply module 1, and the power supply module 1 supplies power to the drive circuit 200 to ensure the normal operation of the drive circuit 200. The drive circuit 200 includes a load module 7, an energy storage module 3, a constant current control module 4 and a sampling signal module 5. The load module 7 includes a first load 71 and a second load 72 connected in series, and the first load 71 is connected to the power supply module 1, so that the power supply module 1 can supply power to the first load 71 and the second load 72, so that the first load 71 and the second load 72 can work normally; one end of the energy storage module 3 is connected to the input end of the first load 71 and the output end of the power supply module 1, and the other end is grounded, so that the energy storage module 3 can be charged when the power supply module 1 outputs a high voltage. When the power supply module 1 outputs a low voltage, the energy storage module 3 supplies power to the load module 7 to avoid large changes in the voltage of the power supply module 1. , the load module 7 cannot work normally; the constant current control module 4 includes a first control unit 411 and a fourth control unit 423 connected in parallel with the second load 72, and a second control unit 413 and a third control unit 421 connected in series with the second load 72 to control the start or stop of the second load 72; the sampling signal module 5 includes a diode D1 and a sampling module 6, the diode D1 is arranged between the power supply module 1 and the energy storage module 3, so that the power supply module 1 can supply power to the energy storage module 3 and the load module 7, and the voltage output by the energy storage module 3 cannot pass through the diode D1 to flow to the power supply module 1, and the sampling module 6 is connected to the output end of the power supply module 1 to sample the output voltage of the power supply module 1, and control the connection or disconnection of the first control unit 411, the second control unit 413, the third control unit 421 and the fourth control unit 423.

[0032] Specifically, the sampling module 6 is connected to the output end of the power supply module 1 , and the connection point is located between the power supply module 1 and the diode D1 , so that the sampling module 6 can directly sample the output voltage of the power supply module 1 , thereby improving the accuracy of the voltage collected by the sampling module 6 .

[0033] The energy storage module 3 includes an energy storage capacitor C1, and the constant current control module 4 includes a resistor R3. One end of the resistor R3 is connected to the first control unit 411 and the second control unit 413, and the other end is connected to the energy storage capacitor C1. The other end of the energy storage capacitor C1 is connected to the first load 71 to form a discharge circuit. Specifically, when the output voltage of the power supply module 1 is reduced to a certain value, one of the first control unit 411 and the second control unit 413 is connected and the other is turned off, so that the load module 7, the resistor R3 and the energy storage module 3 form a closed loop, so that the energy storage capacitor C1 supplies power to the load module 7.

[0034] Specifically, the energy storage module 3 includes a diode D2, one end of the diode D2 is connected to the energy storage capacitor C1, and the other end is grounded to form a charging circuit for the energy storage capacitor C1. Specifically, by setting the energy storage module 3 and grounding the energy storage module 3, when the drive circuit 200 is working, the capacitor can absorb the surge current generated by the outside world, thereby reducing the anti-surge device set in the circuit and reducing the cost of the drive circuit 200; by setting the diode D2, the external current except the power supply module 1 cannot flow into the capacitor module, and then the positive and negative poles of the energy storage module 3 are kept consistent with the power supply module 1, avoiding the change of the positive and negative poles of the energy storage module 3 due to the external voltage input.

[0035] The constant current control module 4 includes a resistor R4, one end of which is connected to the third control unit 421 and the fourth control unit 423, and the other end is grounded. Specifically, when the voltage output by the power supply module 1 is large, one of the third control unit 421 and the fourth control unit 423 is connected and the other is turned off, so that the power supply module 1 can supply power to the load module 7 and form a loop through the grounded end of the resistor R4 to ensure that the load module 7 can work normally.

[0036] The sampling module 6 includes a comparator 61 and a converter 62 connected to the comparator 61, wherein the sampling module 6 samples the output voltage of the power supply module 1, and inputs the sampling result into the comparator 61 for comparison with the fixed reference of the comparator 61. If the sampled voltage is not less than the fixed reference, the comparator 61 outputs a first control signal to control the third control unit 421 and the fourth control unit 423 to be connected or disconnected; if the sampled voltage is less than the fixed reference of the comparator 61, the comparator 61 controls the converter 62 to output a second control signal to control the connection and disconnection of the first control unit 411 and the second control unit 413.

[0037] That is to say, when the voltage of the power supply module 1 is high, one of the third control unit 421 and the fourth control unit 423 is connected and the other is turned off, so that the power supply module 1 supplies power to the load module 7 and also charges the energy storage module 3; when the voltage of the power supply module 1 is low, one of the first control unit 411 and the second control unit 413 is connected and the other is turned off, so that the energy storage module 3 supplies power to the load module 7, thereby preventing the load module 7 from reducing the output power due to the voltage reduction.

[0038] Specifically, the constant current control module 4 is provided with a first control module 41 including a first control unit 411 and a second control unit 413, and a second control module 42 including a third control unit 421 and a fourth control unit 423. When one of the first control unit 411 and the second control unit 413 in the first control module 41 is connected, the third control unit 421 and the fourth control unit 423 in the second control module 42 are both turned off, so that at the same time, only one of the first control unit 411, the second control unit 413, the third control unit 421 and the fourth control unit 423 is connected, and the other three are turned off to achieve the normal operation of the first load 71, and at the same time, the start or stop of the second load 72 can be accurately controlled.

[0039] In other words, the comparator 61 makes a preliminary judgment on the sampled voltage. If the sampled voltage is higher than the rated voltage of the first load 71 , a first control signal is sent to control the operation of the first control module 41 . If the sampled voltage is lower than the rated voltage of the first load 71 , a second control signal is sent to control the operation of the second control module 42 .

[0040] In this embodiment, the load module 7 includes a first load 71 and a second load 72, and the constant current control module 4 includes a first control module 41 and a second control module 42. Of course, in other embodiments, there may be multiple load modules 7 and multiple constant current control modules 4. As long as the first load 71 can maintain normal operation and the second load 72 and more loads can operate at a higher voltage, there is no limitation here.

[0041] The third control unit 421 includes a third controller 422 and a third transistor M3. One end of the third transistor M3 is connected to the third controller 422, the other end is connected to the output end of the second load 72, and another end is grounded. The third controller 422 receives the first control signal and compares it with the third reference of the third controller 422. If the first control signal is equal to the third reference, the third controller 422 controls the third transistor M3 to be connected.

[0042] The fourth control unit 423 includes a fourth controller 424 and a fourth transistor M4. One end of the fourth transistor M4 is connected to the fourth controller 424, the other end is connected to the input end of the second load 72, and the other end is grounded. The fourth controller 424 receives the first control signal and compares it with the fourth reference of the fourth controller 424. If the first control signal is equal to the fourth reference, the fourth controller 424 controls the fourth transistor M4 to be connected.

[0043] Specifically, one end of the third transistor M3 and the grounded end of the fourth transistor M4 are connected, and both are grounded through the resistor R4. The comparator 61 outputs a first control signal according to the range of the sampling voltage. According to the different voltage ranges, the first control signal includes two different values, and the two values ​​correspond to the third reference and the fourth reference respectively. The value of the third reference is greater than the value of the fourth reference. When the third transistor M3 is connected, it means that the output voltage of the power supply module 1 is large, and the first load 71 and the second load 72 are connected in series to share the voltage, so as to avoid damage to the first load 71 due to excessive voltage; when the third transistor M3 is disconnected and the fourth transistor M4 is connected, it means that the output voltage of the power supply module 1 is normal, and the first load 71 can operate normally, that is, the second load 72 is not operating at this time.

[0044] In this embodiment, the comparator 61 outputs a first control signal of different values ​​to control the connection and disconnection of the third transistor M3 and the fourth transistor M4, and the value of the third reference is greater than the value of the fourth reference. Of course, in other embodiments, the value of the third reference may be less than the value of the fourth reference. The comparator 61 may also make a preliminary judgment on the sampled voltage, and then send the sampled voltage to the third controller 422 and the fourth controller 424. After the third controller 422 and the fourth controller 424 make a judgment on the sampled voltage, the connection or disconnection of the third transistor M3 and the fourth transistor M4 is controlled. There is no limitation here.

[0045] The second control unit 413 includes a second controller 414 and a second transistor M2, one end of the second transistor M2 is connected to the second controller 414, the other end is connected to the output end of the second load 72, and another end is connected to the energy storage module 3. The second controller 414 receives a second control signal and compares it with a second reference of the second controller 414. If the second control signal is equal to the second reference, the second controller 414 controls the second transistor M2 to be connected;

[0046] The first control unit 411 includes a first controller 412 and a first transistor M1. One end of the first transistor M1 is connected to the first controller 412, the other end is connected to the input end of the second load 72, and another end is connected to the energy storage module 3. The first controller 412 receives a second control signal and compares it with the first reference of the first controller 412. If the second control signal is equal to the first reference, the first controller 412 controls the first transistor M1 to be connected.

[0047] Specifically, one end of the first transistor M1 and the second transistor M2 is connected to the ground, and both are grounded through the resistor R3. The comparator 61 controls the converter 62 to output the second control signal according to the range of the sampling voltage. According to the different voltage ranges, the second control signal includes two different values, and the two values ​​correspond to the first reference and the second reference respectively. The value of the second reference is greater than the value of the first reference. When the second transistor M2 is connected, it means that the voltage at both ends of the load module 7 is large, and the first load 71 and the second load 72 are connected in series to share the voltage, so as to avoid damage to the first load 71 due to excessive voltage; when the second transistor M2 is disconnected and the first transistor M1 is connected, it means that the voltage at both ends of the load module 7 is normal, and the first load 71 can operate normally, that is, the second load 72 is not operating at this time.

[0048] Specifically, the sampling module 6 also includes a resistor R1 and a resistor R2, wherein the resistor R1 is arranged between the comparator 61 and the power supply module 1, one end of the resistor R2 is connected to the input end of the comparator 61, and the other end is grounded, so that the sampling module 6 forms a sampling loop to sample the voltage of the power supply module 1.

[0049] See also Figure 3 As shown, the present invention also provides a drive controller 100, including a power supply module 1 and a drive circuit 200. The power supply module 1 converts the alternating current of the power grid into direct current to power the drive circuit 200. The drive circuit 200 is partially arranged in the chip 2. The chip 2 is provided with an isolation device, which separates the first control module 41 and the second control module 42, so that a discharge circuit is formed between the first control module 41 and the energy storage module 3.

[0050] Specifically, the power supply module 1 is composed of a rectifier bridge or four diodes, which connects the grid voltage alternating current, converts the current into direct current, and then inputs it into the driving circuit 200.

[0051] Specifically, the input end of the resistor R3 is connected to the output end of the power supply module 1, the output end of the resistor R3 is respectively connected to the pin 1 of the chip 2 and the input end of the resistor R4, and the output end of the resistor R4 is grounded. That is to say, the comparator 61 and the converter 62 are arranged in the chip 2 and connected to the resistor R3 and the resistor R4 through the pin 1 to sample the output voltage of the power supply module 1. Furthermore, the comparator 61 and the converter 62 complete the comparison of the sampled voltage in the chip 2 and send the first control signal or the second control signal to the constant current control module 4.

[0052] The input end of the diode D1 is connected to the output end of the power supply module 1 , and the output end of the diode D1 is respectively connected to the energy storage capacitor C1 , the pin 8 of the chip 2 and the input end of the first load 71 , so that the power supply module 1 can supply power to the energy storage capacitor C1 and the first load 71 .

[0053] The output end of the energy storage capacitor C1 is connected to the diode D2 and then grounded, so that the energy storage capacitor C1 and the power supply module 1 can form a charging circuit; the output end of the energy storage capacitor C1 is connected to the pin 2 of the chip 2, and the output end of the energy storage capacitor C1 is also connected to the resistor R3, and the other end of the resistor R3 is connected to the pin 3 of the chip 2.

[0054] The output end of the first load 71 is connected to pin 6 of chip 2 and the input end of the second load 72 respectively, and the output end of the second load 72 is connected to pin 5 of chip 2. That is to say, the constant current control module 4 is integrated into the chip 2, reducing the components in the drive controller 100, thereby improving the integration of the drive control circuit.

[0055] Among them, the connection method and control method of the sampling module 6 and the constant current control module 4 in the chip 2 are as described above and will not be repeated here in detail. It should be noted that an isolation device is provided in the chip 2 to separate the first control module 41 and the second control module 42, so that there is no current interaction between the first control module 41 and the second control module 42, and the first control module 41 and the energy storage module 3 are connected to form a discharge circuit of the energy storage module 3.

[0056] Pin 4 of chip 2 is connected to resistor R4, and the output end of resistor R4 is grounded. Chip 2 is grounded to prevent static electricity from being generated in chip 2 and causing damage.

[0057] The present invention also provides a lamp, including the aforementioned drive controller 100, a shell, a base and a mask, etc., wherein the structure and connection relationship of the base, the shell and the mask can be set according to the existing technology and are not described in detail here. The first load 71 and the second load 72 are the first light-emitting unit and the second light-emitting unit of the lamp, specifically an LED lamp. By setting the drive circuit 200, the LED lamp will not flicker, thereby improving the protection of human eyes. At the same time, by setting the constant current control module 4 and the energy storage module 3, the LED lamp has a high power factor and a wide voltage input function, thereby improving the practicality of the LED lamp.

[0058] In order to facilitate understanding of the technical solution of the present invention, the following content will specifically illustrate the coordination relationship between the sampling signal module 5, the energy storage module 3, the load module 7 and the constant current control module 4.

[0059] The first light-emitting unit and the second light-emitting unit are connected in series to form an LED light string, the diode D2 and the energy storage capacitor C1 form a charging circuit, and the energy storage capacitor C1, the LED light string, and the constant current control module 4 form a discharge circuit. The diode D1 is arranged between the sampling signal module 5 and the energy storage module 3 to isolate the energy storage capacitor C1 and sample the voltage after the rectifier bridge. The function of the diode D2 is to provide a charging circuit for the energy storage capacitor C1 and isolate the current of the second control module 42.

[0060] See also Figure 4 As shown, the rectified line voltage charges the energy storage capacitor C1. The process from 0 to point B is the initial power-on charging process of the energy storage capacitor C1. This process is not controlled by the IC and the charging is completed quickly.

[0061] See also Figure 5 As shown, within one grid cycle, the phase angle of the grid AC input current from no current to peak current is <65°, and the phase angle when the grid AC input current drops to 5% of the input current peak is ≥90°.

[0062] See also Figure 2 and Figure 6 As shown, under the 220Vac working condition, assuming that the voltage of the first light-emitting unit is 200V, the voltage of the second light-emitting unit is 50V, the minimum starting voltages of the first transistor M1, the second transistor M2, the third transistor M3 and the fourth transistor M4 are all set to 10V, assuming that the feedback voltage point is 210V, the fourth reference vref4=0.6V, the third reference vref3=0.7V, the first reference vref1=0.6V, and the second reference vref2=0.7V. Of course, in other embodiments, the above data can be designed according to actual conditions and are not limited here.

[0063] When the line network voltage is higher than 210V, that is, point A in the figure, the third transistor M3 is turned off and the fourth transistor M4 is turned on, so that the first light-emitting unit works normally. When the line network voltage is higher than 260V, that is, point B in the figure, the third transistor M3 is turned on and the fourth transistor M4 is turned off, so that both the first light-emitting unit and the second light-emitting unit work normally. Among them, the third reference is greater than the fourth reference, so that when the third transistor M3 is turned on, the fourth transistor M4 is turned off.

[0064] When the line network voltage is reduced to 260V, that is, point D in the figure, the third transistor M3 is turned off, and the fourth transistor M4 begins to turn on. At this time, the first light-emitting unit is turned on, and the second light-emitting unit is not turned on. When the line network voltage is reduced to 210V, that is, point E in the figure, the first control signal turns off the third transistor M3 and the fourth transistor M4, and the second control signal turns on the first transistor M1 and the second transistor M2. The energy storage capacitor C1 supplies power to the first light-emitting unit and the second light-emitting unit. At this time, the voltage across the energy storage capacitor C1 is about 310V, the second transistor M2 is turned on, and the first transistor M1 is turned off, so that the first light-emitting unit and the second light-emitting unit both work normally, wherein the second reference is greater than the first reference, so that when the second transistor M2 is turned on, the first transistor M1 is turned off. When the voltage across the energy storage capacitor C1 is reduced to 260V, that is, point F in the figure, the second transistor M2 is turned off, the first transistor M1 is turned on, the first light-emitting unit is turned on, and the energy storage capacitor C1 continues to discharge to 210V, that is, point G in the figure, and the line network voltage also rises to 210V. Then, the above steps are repeated to realize that the first light-emitting unit is always on, and the stroboscopic effect of the lamp is reduced, thereby improving the protection of the lamp to human eyes.

[0065] Among them, G-I is the process of charging the energy storage capacitor C1 by the line voltage, E-G is the process of discharging the energy storage capacitor C1 to the LED light string, and C-E is the process of maintaining the voltage across the energy storage capacitor C1 unchanged.

[0066] t1-t2 and t4-t5 are the times when the line network voltage supplies power to the first light-emitting unit and the first transistor M1, and t2-t3-t4 is the time when the line network voltage supplies power to the first light-emitting unit, the second light-emitting unit and the third transistor M3; t5-t6 is the time when the energy storage capacitor C1 supplies power to the first light-emitting unit, the second light-emitting unit and the second transistor M2, and t6-t7 is the time when the energy storage capacitor C1 supplies power to the first light-emitting unit and the first transistor M1.

[0067] The sampling signal module 5 samples the output voltage of the power supply module 1 and inputs it into the internal comparator 61. The comparator 61 outputs the first control signal EN2 to control the switch of the third transistor M3 and the fourth transistor M4. At the same time, the output port of the comparator 61 can also output the second control signal EN1 through the converter to control the switch of the first transistor M1 and the second transistor M2. When the input voltage is higher than the voltage at point A, the third transistor M3 and the fourth transistor M4 are turned on, and the first transistor M1 and the second transistor M2 are turned off at the same time; when the input voltage is lower than the voltage at point E, the first transistor M1 and the second transistor M2 are turned on, and the third transistor M3 and the fourth transistor M4 are turned off at the same time. By controlling the switches of the first transistor M1, the second transistor M2, the third transistor M3 and the fourth transistor M4, the LED light string can achieve constant current output in the entire line network cycle.

[0068] When the input line voltage is greater than the voltage across the energy storage capacitor C1, that is, in the stage from point A to point B, the current charges the energy storage capacitor C1C1 through the energy storage capacitor C1, the diode D1, and the diode D2, and the charging of the energy storage capacitor C1 is not controlled by the chip 2.

[0069] When the rectified line voltage is less than or equal to the voltage across the energy storage capacitor C1, the input current stops charging the energy storage capacitor C1. When the line voltage is lower than the voltage at point E, the energy storage capacitor C1 discharges the LED light string circuit to maintain the current of the LED light string.

[0070] To sum up, the driving circuit 200 of the present invention is equipped with an energy storage module 3 and a constant current control module 4, so that the load module 7 can achieve constant current output when the voltage fluctuates greatly. It also has the characteristics of high input power factor, wide voltage, no flicker, and strong surge resistance, which further avoids the flicker of the LED light string when the voltage fluctuates, thereby improving the protection of human eyes.

[0071] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A drive circuit connected to a power supply module (1), characterized in that: include: A load module (7) comprising a first load (71) and a second load (72) connected in series, wherein the first load (71) is connected to the power supply module (1); an energy storage module (3) connected to an input end of the first load (71), and charging the energy storage module (3) when the power supply module (1) outputs a high voltage, and supplying power to the load module (7) from the energy storage module (3) when the power supply module (1) outputs a low voltage; A constant current control module (4), comprising a first control unit (411) and a fourth control unit (423) connected in parallel with the second load (72), and a second control unit (413) and a third control unit (421) connected in series with the second load (72), so as to control the start or stop of the second load (72); The sampling signal module (5) comprises a diode D1 and a sampling module (6), wherein the diode D1 is arranged between the power supply module (1) and the energy storage module (3), and the sampling module (6) is connected to the output end of the power supply module (1) to sample the output voltage of the power supply module (1) and control the connection or disconnection of the first control unit (411), the second control unit (413), the third control unit (421) and the fourth control unit (423).

2. The driving circuit according to claim 1, characterized in that: The energy storage module (3) comprises an energy storage capacitor C1, and the constant current control module (4) comprises a resistor R3, one end of the resistor R3 is connected to the first control unit (411) and the second control unit (413), and the other end is connected to the energy storage capacitor C1, and the other end of the energy storage capacitor C1 is connected to the first load (71) to form a discharge circuit.

3. The driving circuit according to claim 2, characterized in that: The energy storage module (3) comprises a diode D2, one end of which is connected to the energy storage capacitor C1, and the other end of which is grounded, so as to form a charging circuit for the energy storage capacitor C1.

4. The driving circuit according to claim 1, characterized in that: The constant current control module (4) comprises a resistor R4, one end of which is connected to the third control unit (421) and the fourth control unit (423), and the other end of which is grounded.

5. The driving circuit according to claim 1, characterized in that: The sampling module (6) comprises a comparator (61), and the sampling module (6) samples the voltage of the power supply module (1), and inputs the sampling result into the comparator (61), and compares it with a fixed reference of the comparator (61); if the sampled voltage is not less than the fixed reference, the comparator (61) outputs a first control signal to control the third control unit (421) and the fourth control unit (423) to be connected or disconnected.

6. The driving circuit according to claim 5, characterized in that: The third control unit (421) comprises a third controller (422) and a third transistor M3, one end of the third transistor M3 is connected to the third controller (422), the other end is connected to the output end of the second load (72), and the other end is grounded, the third controller (422) receives a first control signal and compares it with a third reference of the third controller (422), and if the first control signal is equal to the third reference, the third controller (422) controls the third transistor M3 to be connected; The fourth control unit (423) comprises a fourth controller (424) and a fourth transistor M4, one end of the fourth transistor M4 is connected to the fourth controller (424), the other end is connected to the input end of the second load (72), and the other end is grounded. The fourth controller (424) receives a first control signal and compares it with a fourth reference of the fourth controller (424). If the first control signal is equal to the fourth reference, the fourth controller (424) controls the fourth transistor M4 to be connected.

7. The driving circuit according to claim 5, characterized in that: The sampling module (6) further comprises a converter (62) connected to the comparator (61); if the sampling voltage is less than a fixed reference, the comparator (61) controls the converter (62) to output a second control signal to control the first control unit (411) and the second control unit (413) to be connected or disconnected.

8. The driving circuit according to claim 7, characterized in that: The second control unit (413) comprises a second controller (414) and a second transistor M2, one end of the second transistor M2 is connected to the second controller (414), the other end is connected to the output end of the second load (72), and the other end is connected to the energy storage module (3), the second controller (414) receives a second control signal and compares it with a second reference of the second controller (414), and if the second control signal is equal to the second reference, the second controller (414) controls the second transistor M2 to be connected; The first control unit (411) comprises a first controller (412) and a first transistor M1, one end of the first transistor M1 is connected to the first controller (412), the other end is connected to the input end of the second load (72), and the other end is connected to the energy storage module (3), the first controller (412) receives a second control signal and compares it with a first reference of the first controller (412), and if the second control signal is equal to the first reference, the first controller (412) controls the first transistor M1 to be connected.

9. A drive controller, characterized in that: The invention comprises a power supply module (1) and a driving circuit (200) according to any one of claims 1 to 8, wherein the power supply module (1) converts alternating current (AC) of a power grid into direct current (DC) to supply power to the driving circuit (200), a portion of the driving circuit (200) is arranged in a chip (2), a constant current control module (4) is provided with a first control module (41) comprising a first control unit (411) and a second control unit (413), and a second control module (42) comprising a third control unit (421) and a fourth control unit (423), and an isolation device is arranged in the chip (2), wherein the isolation device separates the first control module (41) and the second control module (42), so that a discharge circuit is formed between the first control module (41) and the energy storage module (3).

10. A lamp, characterized in that: The invention comprises a driving circuit (200) as claimed in any one of claims 1 to 8.

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