Method for improving dynamic response of stroboscopic circuit

Abstract

The invention relates to the technical field of isolated power supplies, and provides a method for improving dynamic response of a stroboflash removing circuit, which is used for improving a conventional stroboflash removing circuit, and is characterized in that a first voltage stabilizing diode and a first diode are arranged between a first input end and a drain electrode of a first MOS (Metal Oxide Semiconductor) tube; the positive electrode of the first voltage stabilizing diode is connected with the positive electrode of the first diode. A second voltage stabilizing diode is arranged among the first diode, the first resistor and the second resistor; the positive electrode of the second voltage stabilizing diode is connected with the positive electrode of the first diode. When the first input end receives a starting signal, the first voltage stabilizing diode and the second voltage stabilizing diode control the voltage of the first input end to flow from the drain electrode and the grid electrode to the source electrode so as to supply power to the LED device. When the first input end receives a jitter signal, the input voltage of the first MOS tube is increased through the first voltage stabilizing diode and the second voltage stabilizing diode, and jitter of the LED equipment is prevented.

Description

Technical Field

[0001] The invention relates to the field of LED lighting, and in particular to a method for improving the dynamic response of a flash-free circuit. Background Art

[0002] At present, in the LED isolation driver power lighting application, due to the single-pole PFC solution, flicker occurs, which brings an uncomfortable experience. The split device circuit is used in the rear pole to solve the flicker problem.

[0003] like Figure 6 However, the traditional circuit has a slow response speed, which may cause uneven dimming and even flickering lights during the dimming process. Figure 7 and Figure 8 It is the jitter phenomenon that occurs in the traditional de-strobing circuit. Summary of the invention

[0004] The present invention proposes a method for improving the dynamic response of a flash removal circuit, which is used to solve the problem that the conventional circuit has a slow response speed, resulting in uneven dimming and even light shaking during the dimming process.

[0005] The present invention proposes a method for improving the dynamic response of a flash-free circuit. The method for improving the dynamic response of a flash-free circuit comprises a first MOS tube and an input end, the input end comprises a first input end and a second input end, the drain of the first MOS tube is electrically connected to the first input end, the positive electrode of the first input end is also electrically connected to the gate of the first MOS tube through a first resistor and a second resistor, the second input end is connected to the first input end through a first capacitor, the second input end is also connected between the first resistor and the second resistor through a second capacitor, and the source of the first MOS tube is connected to an LED output end. The method comprises:

[0006] A second voltage stabilizing diode and a first diode are arranged between the first input terminal and the drain of the first MOS tube; wherein the anode of the second voltage stabilizing diode is connected to the anode of the first diode;

[0007] A first voltage stabilizing diode is arranged between the first diode, the first resistor and the second resistor; wherein the anode of the first voltage stabilizing diode is connected to the anode of the first diode;

[0008] When the first input terminal receives a start signal, the voltage at the first input terminal is controlled to flow from the drain and the gate to the source through the second voltage stabilizing diode and the first voltage stabilizing diode, thereby supplying power to the LED device;

[0009] When the first input terminal receives a jitter signal, the input voltage of the first MOS tube is increased through the second voltage regulator diode and the second voltage regulator diode to prevent the LED device from jittering.

[0010] Further, when the voltages of the first input terminal and the first capacitor become lower, and the voltage of the second capacitor is higher than the voltage of the first capacitor, a jitter signal is generated.

[0011] Furthermore, the LED devices include: LED lighting devices, LED display devices, LED signal indication devices, LED backlight devices, LED decorative devices and LED intelligent control devices.

[0012] Furthermore, when the LED device is an LED display screen;

[0013] A fast loop is established by adding a current source between the first input terminal and the first diode;

[0014] When the LED display screen has a large high-frequency change, the fast loop will discharge the LED display screen before the first output section, and the LED display screen changes the size of its input current to suppress the high-frequency drastic change of the LED display screen.

[0015] Furthermore, the first voltage stabilizing diode is also used to respond to the LED device and obtain a first voltage corresponding to the expected frequency of the LED device;

[0016] The real-time voltage of the first input terminal is converted into a first voltage corresponding to the expected frequency, and the threshold voltage of the first output terminal is adjusted according to the real-time voltage and the first voltage.

[0017] Furthermore, the first input terminal is also used for:

[0018] Detect the peak voltage of the LED device, determine the sampling signal of the peak voltage, and analyze and confirm the reference signal of the LED device;

[0019] Wherein, the voltage sampling signal of the LED device is determined by the real-time voltage of the LED device, the voltage sampling signal is compared with the reference signal at the input end of the LED device, and when the voltage sampling signal reaches the reference signal at the input end of the ED device, a compensation voltage is set at the first input end to adjust the voltage of the LED device;

[0020] When collecting the peak voltage, the weighted average of the previous m peak voltages is used, where m is a natural number.

[0021] Furthermore, the first voltage stabilizing diode and the second voltage stabilizing diode are provided with a voltage stabilizing upper limit value and a voltage stabilizing lower limit value.

[0022] Furthermore, the voltage stabilization upper limit value and the voltage stabilization lower limit value are switching thresholds of the first MOS tube.

[0023] Furthermore, the first MOS tube is a PMOS switch tube, and the driving voltage of the PMOS switch tube is a reference voltage of the LED device.

[0024] The beneficial effects of the present invention are:

[0025] The present invention can effectively eliminate or reduce the LED stroboscopic phenomenon caused by power supply voltage fluctuations by setting a voltage stabilizing diode and a diode in the circuit, thereby improving the stability and comfort of LED lighting. The circuit design allows for a quick response when a start signal is received, and provides a stable power supply to the LED device by controlling the voltage flow direction, thereby improving the dynamic response performance of the circuit; when the circuit receives a jitter signal, by increasing the input voltage of the first MOS tube, the LED brightness jitter caused by voltage fluctuations can be prevented, thereby ensuring the stable operation of the LED. The first voltage stabilizing diode and the second voltage stabilizing diode can limit the voltage within a safe range, protecting the LED device from damage caused by excessive voltage.

[0026] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0027] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 It is a schematic diagram of the newly added circuit of the present invention combined with the traditional anti-flash circuit in the embodiment of the present invention;

[0030] Figure 2 It is a schematic diagram of the charging process of the newly added circuit of the present invention combined with the traditional anti-flash circuit in the embodiment of the present invention;

[0031] Figure 3 It is a schematic diagram of the discharge of the newly added circuit of the present invention combined with the traditional anti-flash circuit in the embodiment of the present invention;

[0032] Figure 4 The first fast dynamic response diagram of the newly added circuit of the present invention combined with the traditional de-flash circuit in the embodiment of the present invention;

[0033] Figure 5 The second fast dynamic response diagram of the newly added circuit of the present invention combined with the traditional de-flash circuit in the embodiment of the present invention;

[0034] Figure 6 A schematic diagram of the structure of a conventional flash removal circuit in an embodiment of the present invention;

[0035] Figure 7 Schematic diagram of dimming in a conventional flash removal circuit in an embodiment of the present invention;

[0036] Figure 8 A diagram showing the jitter phenomenon of a conventional de-strobing circuit in an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0038] like Figure 1 As shown, this embodiment provides a method for improving the dynamic response of a flash-free circuit, wherein the flash-free circuit includes a first MOS tube Q1 and an input end, wherein the input end includes a first input end IN1 and a second input end IN2, wherein the drain of the first MOS tube Q1 is electrically connected to the first input end IN1, wherein the positive electrode of the first input end IN1 is also electrically connected to the gate of the first MOS tube Q1 through a first resistor R1 and a second resistor R2, wherein the second input end IN2 is connected to the first input end IN1 through a first capacitor C2, wherein the second input end IN2 is also connected between the first resistor R1 and the second resistor R2 through a second capacitor C2, wherein the source of the first MOS tube Q1 is connected to the LED output end, wherein the method includes:

[0039] A second voltage stabilizing diode ZD2 and a first diode D1 are arranged between the first input terminal IN1 and the drain of the first MOS transistor Q1; wherein the anode of the second voltage stabilizing diode ZD2 is connected to the anode of the first diode DS1;

[0040] A first voltage zener diode ZD1 is arranged between the first diode DS1, the first resistor R1 and the second resistor R2; wherein the anode of the first voltage zener diode ZD1 is connected to the anode of the first diode DS1;

[0041] When the first input terminal IN1 receives a start signal, the voltage of the first input terminal IN1 is controlled to flow from the drain and the gate to the source through the second voltage zener diode ZD2 and the first voltage zener diode ZD1 to power the LED device;

[0042] When the first input terminal receives a jitter signal, the input voltage of the first MOS tube Q1 is increased by the second voltage stabilizing diode ZD2 and the first voltage stabilizing diode to prevent the LED device from jittering.

[0043] The principle of the above technical solution is:

[0044] In the actual implementation process, Figure 2 and Figure 4As shown, when the power is turned on, the first input terminal IN1IN1 and the second input terminal IN2 rectify and filter the connected AC power to generate DC power. In the actual implementation process, a rectifier diode D1 is also arranged between the first input terminal IN1 and the drain of the first MOS tube Q1, and the DC power is rectified by the rectifier diode D1.

[0045] During the startup process, the input DC power flows to the first Zener diode ZD1 through the first resistor R1, the second Zener diode ZD2 and the first diode DS1, thereby charging the second capacitor C2. The second resistor R2 provides voltage to the first MOS tube Q1, and the first MOS tube Q1 is turned on, and the power flows from the drain to the source, thereby realizing startup.

[0046] In the steady state of operation, the input direct current is transmitted by the first capacitor C1 and the first resistor R1, and then passes through the second voltage stabilizing diode ZD2, the first diode DS1, the first voltage stabilizing diode ZD1, the second capacitor C2, the second resistor R2 to the first MOS tube Q1, and the voltage flows from the drain to the source, and flows to the positive and negative terminals of the LED device through the fifth resistor R5 and the sixth resistor R6, forming a loop;

[0047] In the actual operation of the present invention, if LED+ and LED- are short-circuited, the MOS is not damaged.

[0048] When short-circuited, the peak current is relatively large, and the fifth resistor R5 and the sixth resistor R6 are used for current limiting.

[0049] like Figure 3 and Figure 5 As shown, when flicker removal is required, that is, when the voltages of the first input terminal IN1 and the first capacitor C1 become low, the voltage of the second capacitor C2 is higher than the voltage of the first capacitor C1, and the second capacitor C3 causes the second zener diode ZD2 and the first zener diode ZD1 to be fed back to the drain of the first MOS tube Q1, thereby preventing light jitter.

[0050] The beneficial effects of the above technical solution are:

[0051] The present invention can effectively eliminate or reduce the LED stroboscopic phenomenon caused by power supply voltage fluctuations by setting a voltage stabilizing diode and a diode in the circuit, thereby improving the stability and comfort of LED lighting. The circuit design allows for a quick response when a start signal is received, and provides a stable power supply to the LED device by controlling the voltage flow direction, thereby improving the dynamic response performance of the circuit; when the circuit receives a jitter signal, by increasing the input voltage of the first MOS tube Q1, the LED brightness jitter caused by voltage fluctuations can be prevented, thereby ensuring the stable operation of the LED. The first voltage stabilizing diode ZD1 and the second voltage stabilizing diode ZD2 can limit the voltage within a safe range, protecting the LED device from damage caused by excessive voltage.

[0052] As an embodiment of the present invention: after the first input terminal IN1 receives the start signal, the voltage of the first diode DS1 flows into the first voltage stabilizing diode ZD1 and charges the second capacitor C2.

[0053] The principle of the above technical solution is:

[0054] When the first input terminal IN1 receives the start signal, the first diode DS1 converts the received start signal into a corresponding voltage signal and transmits the voltage signal to the first voltage zener diode ZD1. At the same time, since the signal conversion process consumes a certain amount of energy, the first diode DS1 will also pre-charge the second voltage zener diode ZD2 and the second capacitor C2, and then discharge when preventing strobe.

[0055] As an embodiment of the present invention: when the voltages of the first input terminal IN1 and the first capacitor C1 become low, and the voltage of the second capacitor C2 is higher than the voltage of the first capacitor C1, a start signal is generated.

[0056] The principle of the above technical solution is:

[0057] In the anti-strobe circuit, when the voltage of the first input terminal IN1 becomes low, and the voltage of the second capacitor C2 is higher than the voltage of the first capacitor C1, the start signal may be triggered. This is because, in the anti-strobe circuit, there is usually a reference voltage for comparing the voltages of the first input terminal IN1 and the first capacitor C1. If the voltage difference between the two is found to be too large, it will be considered that a fault or abnormality has occurred, thereby generating a jitter signal. At this time, the voltage of the second capacitor C2 will be used to compensate for the voltage difference between the first input terminal IN1 and the first capacitor C1 to keep the voltage balance between the two as much as possible.

[0058] As an embodiment of the present invention: the LED device includes: LED lighting equipment, LED display equipment, LED signal indication equipment, LED backlight equipment, LED decoration equipment and LED intelligent control equipment.

[0059] The principle of the above technical solution is:

[0060] The de-strobing circuit dynamic response method is not only applicable to LED lighting equipment, but also to other types of LED equipment, including but not limited to LED display equipment, LED signal indication equipment, LED backlight equipment, LED decorative equipment and LED intelligent control equipment, etc. When these devices use the de-strobing circuit for dynamic response, the performance and reliability of the equipment can be effectively improved, so that they can work better in different application scenarios.

[0061] As an embodiment of the present invention: when the LED device is an LED display screen;

[0062] A fast loop is established by adding a current source between the first input terminal IN1 and the first diode DS1;

[0063] When the LED display screen has a large high-frequency change, the fast loop will discharge the LED display screen before the first output terminal IN1, and the LED display screen changes the size of its input current to suppress the high-frequency drastic change of the LED display screen.

[0064] The principle of the above technical solution is:

[0065] When the LED device is an LED display screen, a fast loop is established by adding a current source between the first input terminal IN1 and the first diode DS1. The fast loop is used to quickly adjust the current in the circuit, suppress and reduce the frequent switching phenomenon of the LED display screen caused by excessive or insufficient input current, and improve the service life and viewing experience of the LED display screen.

[0066] Specifically, when the LED display screen undergoes large high-frequency changes, due to the introduction of a fast loop between the first input terminal IN1 and the first diode DS1, the voltage and current on the LED display screen can be immediately adjusted accordingly, avoiding the time delay of the traditional first output terminal discharging the LED display screen, and greatly shortening the flickering time of the LED display screen due to high-frequency changes.

[0067] In addition, by adding a current source between the first input terminal IN1 and the first diode DS1, the voltage difference between the first input terminal IN1 and the first diode DS1 can be limited, thereby preventing damage caused by an excessively large voltage difference and improving the reliability of the anti-flash circuit.

[0068] As an embodiment of the present invention: the second voltage stabilizing diode ZD2 is further used to respond to the LED device and obtain a first voltage corresponding to the expected frequency of the LED device;

[0069] The real-time voltage of the first input terminal IN1 is converted into a first voltage corresponding to the expected frequency, and the threshold voltage of the first output terminal is adjusted according to the comparison difference between the real-time voltage and the first voltage.

[0070] The principle of the above technical solution is:

[0071] By using the second voltage stabilizing diode ZD2 to obtain the first voltage corresponding to the expected frequency of the LED device, more accurate voltage control is achieved, thereby improving the dynamic response performance of the anti-strobe circuit, especially in high-precision application scenarios such as LED display screens.

[0072] When the second voltage stabilizing diode ZD2 detects the expected frequency of the LED device, it will feed back the voltage corresponding to this frequency to the first input terminal. Then, based on this feedback voltage and the real-time voltage of the first input terminal, an optimal threshold voltage is calculated. This threshold voltage will be used to adjust the voltage of the first output terminal so that it always remains at the precise voltage level corresponding to the expected frequency.

[0073] As an embodiment of the present invention: the first input terminal is also used for:

[0074] Detect the peak voltage of the LED device, determine the sampling signal of the peak voltage, and analyze and confirm the reference signal of the LED device;

[0075] Wherein, the voltage sampling signal of the LED device is determined by the real-time voltage of the LED device, the voltage sampling signal is compared with the reference signal at the input end of the LED device, and when the voltage sampling signal reaches the reference signal at the input end of the ED device, a compensation voltage is set at the first input end to adjust the voltage of the LED device;

[0076] When collecting the peak voltage, the weighted average of the previous m peak voltages is used, where m is a natural number.

[0077] The principle of the above technical solution is:

[0078] By monitoring the real-time voltage of the LED device, we can obtain information about its peak voltage. Then, we compare it with the reference signal of the LED device. If the voltage sampling signal reaches the reference signal, we set the corresponding compensation voltage at the first input terminal to adjust the voltage of the LED device. This processing method allows our anti-strobe circuit to better adapt to the voltage changes of the LED device and further improve the dynamic response performance.

[0079] In addition, when collecting peak voltage, we use the weighted average of the previous m peak voltages. This method can make our voltage sampling results more stable and accurate by taking a weighted average of multiple groups of peak voltages.

[0080] As an embodiment of the present invention: the first voltage stabilizing diode ZD1 and the second voltage stabilizing diode ZD2 are provided with a voltage stabilizing upper limit value and a voltage stabilizing lower limit value.

[0081] The principle of the above technical solution is that the voltage upper limit of the first voltage regulator diode can be set to a certain maximum threshold value. When the voltage at the first input terminal exceeds this threshold value, the first voltage regulator diode will start to adjust and guide the voltage to a suitable range. Similarly, the voltage upper limit of the second voltage regulator diode is set to a smaller threshold value. When the voltage at the first input terminal is close to this threshold value, the second voltage regulator diode will also start to adjust to ensure that the input voltage of the first MOS tube is always within a suitable range.

[0082] It not only improves the dynamic response performance of the anti-flash circuit, but also can avoid, to a certain extent, the unstable operation of the first MOS tube caused by over-regulation of the voltage regulator diode.

[0083] As an embodiment of the present invention: the voltage stabilization upper limit value and the voltage stabilization lower limit value are switch thresholds of the first MOS tube.

[0084] In a specific implementation, the voltage regulation upper limit value of the first voltage regulator diode is set to the switching threshold value of the first MOS tube. This means that when the voltage at the first input terminal exceeds this threshold value, the first voltage regulator diode will start to adjust and guide the voltage to a suitable range. In this way, it can be ensured that in most cases, the first MOS tube can work stably, and the dynamic response performance of the circuit is improved. The voltage regulation lower limit value of the second voltage regulator diode is also set to the switching threshold value of the first MOS tube. This means that when the voltage at the first input terminal is lower than this threshold value, the second voltage regulator diode will start to adjust and increase the voltage to a suitable range. In this way, it can be ensured that in most cases, the first MOS tube can work stably, and the dynamic response performance of the circuit is improved.

[0085] As an embodiment of the present invention: the first MOS tube Q1 is a PMOS switch tube, and the driving voltage of the PMOS switch tube is the reference voltage of the LED device.

[0086] The principle of the above technical solution is:

[0087] When the microcontroller outputs a high level, the gate voltage of the PMOS switch tube is higher than the source voltage, the PMOS switch tube is turned on, and the current can flow from the positive pole of the power supply to the LED, through the current limiting resistor, and then to the negative pole of the power supply, and the LED lights up. When the microcontroller outputs a low level, the gate voltage of the PMOS switch tube is lower than the source voltage, the PMOS switch tube is cut off, the current cannot flow through the LED, and the LED goes out.

[0088] The beneficial effects of the above technical solution are:

[0089] Since the driving voltage of the PMOS switch tube matches the reference voltage of the LED device, it can ensure that the LED device works at the optimal operating voltage, improving the brightness and stability of the LED. The use of PMOS switch tubes can directly drive the LED, reducing additional voltage conversion circuits, simplifying the overall circuit design, and reducing costs.

[0090] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for improving the dynamic response of a flash-free circuit, wherein the flash-free circuit comprises a first MOS tube and an input end, wherein the input end comprises a first input end and a second input end, wherein the drain of the first MOS tube is electrically connected to the first input end, wherein the positive electrode of the first input end is also electrically connected to the gate of the first MOS tube through a first resistor and a second resistor, wherein the second input end is connected to the first input end through a first capacitor, wherein the second input end is also connected between the first resistor and the second resistor through a second capacitor, wherein the source of the first MOS tube is connected to the LED output end, wherein: The method comprises: A second voltage stabilizing diode and a first diode are arranged between the first input terminal and the drain of the first MOS tube; wherein the anode of the second voltage stabilizing diode is connected to the anode of the first diode; A first voltage stabilizing diode is arranged between the first diode, the first resistor and the second resistor; wherein the anode of the first voltage stabilizing diode is connected to the anode of the first diode; When the first input terminal receives a start signal, the voltage at the first input terminal is controlled to flow from the drain and the gate to the source through the second voltage stabilizing diode and the first voltage stabilizing diode, thereby supplying power to the LED device; When the first input terminal receives a jitter signal, the input voltage of the first MOS tube is increased through the second voltage regulator diode and the second voltage regulator diode to prevent the LED device from jittering.

2. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: After the first input terminal receives the start signal, the voltage of the first diode flows to the second voltage regulator diode and charges the second capacitor.

3. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: When the voltages of the first input terminal and the first capacitor become low, and the voltage of the second capacitor is higher than the voltage of the first capacitor, a jitter signal is generated.

4. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The LED devices include: LED lighting devices, LED display devices, LED signal indicating devices, LED backlight devices, LED decorative devices and LED intelligent control devices.

5. A method for improving the dynamic response of a flash-free circuit as claimed in claim 4, characterized in that: When the LED device is an LED display screen; A fast loop is established by adding a current source between the first input terminal and the first diode; When the LED display screen has a large high-frequency change, the fast loop will discharge the LED display screen before the first output section, and the LED display screen changes the size of its input current to suppress the high-frequency drastic change of the LED display screen.

6. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The first voltage stabilizing diode is further used to respond to the LED device and obtain a first voltage corresponding to the expected frequency of the LED device; The real-time voltage of the first input terminal is converted into a first voltage corresponding to the expected frequency, and the threshold voltage of the first output terminal is adjusted according to the real-time voltage and the first voltage.

7. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The first input terminal is also used for: Detect the peak voltage of the LED device, determine the sampling signal of the peak voltage, and analyze and confirm the reference signal of the LED device; Wherein, the voltage sampling signal of the LED device is determined by the real-time voltage of the LED device, the voltage sampling signal is compared with the reference signal at the input end of the LED device, and when the voltage sampling signal reaches the reference signal at the input end of the ED device, a compensation voltage is set at the first input end to adjust the voltage of the LED device; When collecting the peak voltage, the weighted average of the previous m peak voltages is used, where m is a natural number.

8. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The first voltage stabilizing diode and the second voltage stabilizing diode are provided with a voltage stabilizing upper limit value and a voltage stabilizing lower limit value.

9. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The upper voltage stabilization line value and the lower voltage stabilization line value are the switching thresholds of the first MOS tube.

10. A method for improving the dynamic response of a flash-free circuit as claimed in claim 1, characterized in that: The first MOS tube is a PMOS switch tube, and the driving voltage of the PMOS switch tube is the reference voltage of the LED device.

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