Slow-start LED circuit and LED lamp

Abstract

The utility model provides a slow start LED circuit and an LED lamp, the slow start LED circuit comprises a rectification circuit, a transformation output circuit and a detection control circuit, the transformation output circuit comprises a DC input circuit, a DC output circuit, an isolation driver and a transformer, and the detection control circuit comprises a power-on detection circuit and a power supply circuit. The power-on detection circuit comprises a series resistor and a first resistor, the power supply circuit comprises a second resistor, a three-port integrator and a frequency modulator, when the slow start LED circuit is powered on, the output current of the isolation driver can be changed through switching of the switch, and at the moment, the slow start LED circuit memorizes the corresponding output current state; according to the invention, the LED lamp enters a specified current state at the moment when the user electrifies the LED lamp next time, then the output current slowly rises, the light can adapt to the corresponding light state for the human eyes in the time period from dark to bright, and the emitted light is friendly to the human eyes, so that the function of slowly lighting the lamp is realized, and sudden lighting is avoided.

Description

Technical Field

[0001] The present disclosure relates to the technical field of lamp lighting, and in particular to a soft-start LED circuit and an LED lamp. Background Technique

[0002] With the development of lamp technology, especially the development of LED light sources and driving technologies, LED lamps are developing towards intelligence and personalization; due to the fast response speed of LED light sources, the response time is at the microsecond level, and basically as soon as the switch is turned on, it will light up immediately. For example, in the prior arts such as CN202085371U and CN206498559U.

[0003] However, in some specific scenarios, when the human eye has adapted to a lightless or low-light environment, if the lamp is turned on at this time, due to the human eye not adapting to the change of light, the suddenly lit lamp will make people feel very dazzling, so the emitted light is not friendly to the human eye. Utility Model Content

[0004] The purpose of the present disclosure is to overcome the deficiencies in the prior art and provide a soft-start LED circuit and an LED lamp that can control the output current of an isolation driver and can achieve the function of slowly lighting up.

[0005] The purpose of the present disclosure is achieved through the following technical solutions:

[0006] A soft-start LED circuit includes:

[0007] A rectifying circuit for converting alternating current into direct current;

[0008] A voltage transformation output circuit for receiving direct current, transforming the direct current and outputting it to a lamp, including a direct current input circuit, a direct current output circuit, an isolation driver and a transformer. The input end of the direct current input circuit is connected to the output end of the rectifying circuit, the output end of the direct current input circuit is electrically connected to the input end of the direct current output circuit through the transformer, the power generation end of the direct current input circuit is respectively connected to the power connection end of the isolation driver and the input end of the transformer, and the output end of the isolation driver is connected to the input end of the transformer;

[0009] The detection and control circuit includes a power-on detection circuit and a power supply circuit. The power-on detection circuit includes a series-connected resistor and a first resistor. The first end of the series-connected resistor is connected to the input end of the rectification circuit and the power generation two-terminal of the DC input circuit respectively. The second end of the series-connected resistor is connected to the first end of the first resistor, and the second end of the first resistor is grounded. The power supply circuit includes a second resistor, a three-port integrator, and a frequency modulator. The first end of the first resistor is connected to the signal receiving end of the frequency modulator. The signal output end of the frequency modulator is connected to the control end of the isolation driver. The first end of the second resistor is connected to the input end of the transformer. The second end of the second resistor is connected to the input end of the three-port integrator. The grounding end of the three-port integrator is grounded, and the output end of the three-port integrator is connected to the power connection end of the frequency modulator.

[0010] In one embodiment, the series-connected resistor includes a third resistor, a fourth resistor, and a fifth resistor. The first end of the first resistor is connected to the power generation two-terminal of the DC input circuit through the fifth resistor, the fourth resistor, and the third resistor in sequence.

[0011] In one embodiment, at least one of the third resistor, the fourth resistor, and the fifth resistor is a variable resistor.

[0012] In one embodiment, the power-on detection circuit further includes a first capacitor. The upper half end of the first capacitor is connected to the first end of the first resistor, and the lower half end of the first capacitor is connected to the second end of the first resistor.

[0013] In one embodiment, the power supply circuit further includes a sixth resistor. The signal output end of the frequency modulator is connected to the control end of the isolation driver through the sixth resistor.

[0014] In one embodiment, the sixth resistor is a variable resistor.

[0015] In one embodiment, the power supply circuit further includes a second capacitor. The upper half end of the second capacitor is connected to the input end of the three-port integrator, and the lower half end of the second capacitor is grounded.

[0016] In one embodiment, the power supply circuit further includes a third capacitor. The upper half end of the third capacitor is connected to the output end of the three-port integrator, and the lower half end of the third capacitor is grounded.

[0017] In one embodiment, the power supply circuit further includes a general diode. The anode of the general diode is connected to the input end of the transformer, and the cathode of the general diode is connected to the first end of the second resistor.

[0018] An LED lamp includes the soft-start LED circuit according to any one of the above embodiments.

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

[0020] When the soft-start LED circuit is powered on and the LED lamp works, the output current of the isolation driver can be changed to any current state through switch switching. At this time, the soft-start LED circuit memorizes the corresponding output current state, so that when the user powers on the LED lamp next time, it enters the specified current state instantly, and then the output current rises slowly. The period when the light changes from dark to bright can allow the human eye to adapt to the corresponding light state, thus realizing the function of slow lighting and avoiding sudden lighting. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present disclosure, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 is a schematic structural diagram of a soft-start LED circuit in an embodiment;

[0023] Figure 2 is Figure 1 the circuit diagram of the rectifying circuit and the voltage transformation output circuit in the soft-start LED circuit shown;

[0024] Figure 3 is Figure 1 the circuit diagram of the detection and control circuit in the soft-start LED circuit shown;

[0025] Figure 4 is Figure 1 the working principle diagram of the soft-start LED circuit shown.

[0026] Reference numerals: 10, soft-start LED circuit; 100, rectifying circuit; 200, voltage transformation output circuit; 210, DC input circuit; 220, DC output circuit; 300, detection and control circuit; 310, power-on detection circuit; 320, power supply circuit; T1, transformer; U1, isolation driver; U2, frequency modulator; U3, three-port integrator; R25, first resistor; R8, second resistor; R22, third resistor; R23, fourth resistor; R24, fifth resistor; R26, sixth resistor; C9, first capacitor; EC3, second capacitor; C7, third capacitor; D2, general diode. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present disclosure are shown in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present disclosure can be understood more thoroughly and comprehensively.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present disclosure belongs. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0030] To better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure will be further described in detail below with specific embodiments:

[0031] Please refer to Figures 1 to 3 , which is a soft-start LED circuit 10 according to an embodiment of the present utility model, including a rectifying circuit 100, a voltage-transforming output circuit 200 and a detection control circuit 300.

[0032] As Figure 2 shown, the rectifying circuit 100 is used to convert alternating current into direct current; the voltage-transforming output circuit 200 is used to receive direct current and output the transformed direct current to the lamp, including a direct current input circuit 210, a direct current output circuit 220, an isolation driver U1 and a transformer T1. The input end of the direct current input circuit 210 is connected to the output end of the rectifying circuit 100. The output end of the direct current input circuit 210 is electrically connected to the input end of the direct current output circuit 220 through the input end T1A and the output end T1B of the transformer T1. One power generation end of the direct current input circuit 210 is respectively connected to the power connection end of the isolation driver U1 and the input end T1A of the transformer T1. The output end of the isolation driver U1 is connected to the input end T1A of the transformer T1.

[0033] As Figure 3As shown, the detection control circuit 300 includes a power-on detection circuit 310 and a power supply circuit 320. The power-on detection circuit 310 includes a series-connected resistor and a first resistor R25. The first end of the series-connected resistor is respectively connected to the input end of the rectification circuit 100 and the power generation two-terminal of the DC input circuit 210. The second end of the series-connected resistor is connected to the first end of the first resistor R25, and the second end of the first resistor R25 is grounded; the power supply circuit 320 includes a second resistor R8, a three-port integrator U3, and a frequency modulator U2. The first end of the first resistor R25 is connected to the signal receiving end of the frequency modulator U2. The signal output end of the frequency modulator U2 is connected to the control end of the isolation driver U1. The first end of the second resistor R8 is connected to the input end T1A of the transformer T1. The second end of the second resistor R8 is connected to the input end of the three-port integrator U3. The grounded end of the three-port integrator U3 is grounded, and the output end of the three-port integrator U3 is connected to the power connection end of the frequency modulator U2.

[0034] It can be understood that in combination with Figure 4 As shown, the rectification circuit 100 and the transformer output circuit 200 constitute an AC-DC conversion module, that is, module 1, and the detection control circuit 300 constitutes a slow-light detection control module, that is, module 2, which is used to detect the on / off state and provide a pulse width modulation (PWM) control signal for the AC-DC conversion module.

[0035] In this embodiment, when the slow-start LED circuit 10 is powered on, the output current of the isolation driver U1 can be changed to any current state through switch switching. At this time, the slow-start LED circuit 10 memorizes the corresponding output current state, so that the user can enter the specified current state instantly when the LED lamp is powered on next time. Subsequently, the output current slowly rises, and the time period when the light gradually brightens from dark can allow the human eye to adapt to the corresponding light state, thus realizing the function of slow lighting and avoiding sudden brightening.

[0036] It can be understood that when the slow-start LED circuit 10 is powered on, the AC-DC conversion module, that is, the isolation driver U1 and the transformer T1, work to establish the power supply voltage. At the same time, the power supply powers the slow-light detection control module, that is, the power-on detection circuit 310. When the circuit is powered on, the current passes through the series-connected resistor and enters from the signal receiving end of the frequency modulator U2. During this period, the series-connected resistor and the first resistor R25 divide the voltage. At this time, after the frequency modulator U2 receives the signal, it judges the number of on / off operations and the current state at this time, and outputs a corresponding PWM signal from the signal output end of the frequency modulator U2 to the isolation driver U1 to control the current state of the isolation driver U1. After being in the corresponding state, the signal output end of the frequency modulator U2 outputs a corresponding signal and the signal slowly increases, so that the current output by the isolation driver U1 slowly increases, thus realizing the effect of slow lighting.

[0037] Specifically, whenever the switch is toggled, the current output by the isolation driver U1 is adjusted from large to small, that is, the light intensity is adjusted from bright to dim. If there is no switching action after toggling to a specified mode for a certain period of time, the slow-brightness detection control module records the state at the specified current, and the next time power is applied, it is also the specified state. Then, the output current in the specified state slowly rises to the normal state, so that the light intensity of the LED lamp slowly rises to the light intensity during normal operation in the specified state. When the switch is toggled a certain number of times (assumed to be 6 times), the output current returns to the state during normal operation.

[0038] In this embodiment, the signal receiving end of the frequency modulator U2 is the input / output terminal IO, which is used to receive the power-on signal. The signal output end of the frequency modulator U2 is the PWM terminal, which is used to output a PWM signal according to the number of power-on and power-off times and the power-on current state. The control end of the isolation driver U1 is the brightness control terminal DIM. The DIM terminal is used to receive the PWM signal after filtering through a resistor-capacitor circuit (i.e., resistor R13, capacitor C3, and capacitor C5). Thus, when the PWM signal is transmitted to the DIM terminal, it has the effect of adjusting the light intensity. The output end of the isolation driver U1 is the DRAIN terminal, which is used to output a corresponding output current according to the PWM signal state output by the frequency modulator U2, and is output to the lamp through the transformer T1 after voltage transformation, so that the lamp lights up. Further, the model of the isolation driver U1 is BP3176BF; and / or, the model of the three-port integrator U3 is HC7533.

[0039] Further, as Figure 3 shown, the series-connected resistors include the third resistor R22, the fourth resistor R23, and the fifth resistor R24. The first end of the first resistor R25 is connected to the power generation two-terminal of the DC input circuit 210 through the fifth resistor R24, the fourth resistor R23, and the third resistor R22 in sequence. When the circuit is powered on, the first resistor R25, the third resistor R22, the fourth resistor R23, and the fifth resistor R24 divide the voltage, so that the signal receiving end of the frequency modulator U2 receives a corresponding signal according to the current voltage, avoiding the situation that the voltage is too large and affecting the frequency modulator U2 from receiving the power-on signal. Further, at least one of the third resistor R22, the fourth resistor R23, and the fifth resistor R24 is a variable resistor. When one, two, or three of the third resistor R22, the fourth resistor R23, and the fifth resistor R24 are variable resistors, by adjusting the resistance value of one, two, or three of the third resistor R22, the fourth resistor R23, and the fifth resistor R24, the resistance ratio of the third resistor R22, the fourth resistor R23, and the fifth resistor R24 is adjusted, so as to adjust the voltage of the signal receiving end when the frequency modulator U2 receives the power-on signal, and ensure the state of the signal output by the frequency modulator U2 to the isolation driver U1.

[0040] As Figure 3As shown, in one embodiment, the power-on detection circuit 310 further includes a first capacitor C9. The upper half of the first capacitor C9 is connected to the first end of the first resistor R25, and the lower half of the first capacitor C9 is connected to the second end of the first resistor R25. It can be understood that the first capacitor C9 is in parallel with the first resistor R25 to form a capacitor-resistor circuit. When the circuit is powered on, the first capacitor C9 can filter the power-on signal to avoid interference from redundant signals and ensure that the frequency modulator U2 can receive the power-on signal normally.

[0041] As Figure 3 shown, in one embodiment, the power supply circuit 320 further includes a sixth resistor R26. The signal output end of the frequency modulator U2 is connected to the control end of the isolation driver U1 through the sixth resistor R26. It can be understood that when the frequency modulator U2 outputs a signal according to the switch switching times status, a sixth resistor R26 can be set between the signal output end of the frequency modulator U2 and the control end of the isolation driver U1 to limit the current of the output PWM control signal, thereby protecting the signal output end of the frequency modulator U2 and the control end of the isolation driver U1 and avoiding the situation that the frequency modulator U2 and the isolation driver U1 are damaged. Further, the sixth resistor R26 is a variable resistor. When the sixth resistor R26 is a variable resistor, the resistance value of the sixth resistor R26 can be adjusted to correspondingly adjust the current when the isolation driver U1 receives the signal, ensuring that the isolation driver U1 outputs a corresponding output current according to the received PWM signal status.

[0042] As Figure 3 shown, in one embodiment, the power supply circuit 320 further includes a second capacitor EC3. The upper half of the second capacitor EC3 is connected to the input end of the three-port integrator U3, and the lower half of the second capacitor EC3 is grounded. It can be understood that when the current flows from the input end of the transformer T1 through the second resistor R8 to the input end of the three-port integrator U3, the second capacitor EC3 stabilizes the voltage at the input end of the three-port integrator U3 to avoid the situation that the three-port integrator U3 is damaged due to a voltage mutation. Further, the capacitance of the second capacitor EC3 is 10 μF, which can be used to filter low-frequency signals.

[0043] As Figure 3 shown, in one embodiment, the power supply circuit 320 further includes a third capacitor C7. The upper half of the third capacitor C7 is connected to the output end of the three-port integrator U3, and the lower half of the third capacitor C7 is grounded. It can be understood that when the current is output from the output end of the three-port integrator U3, the third capacitor C7 stabilizes the voltage at the output end of the three-port integrator U3 to avoid the situation that the three-port integrator U3 is damaged due to a voltage mutation, and at the same time enables the frequency modulator U2 to be normally powered on to ensure that the frequency modulator U2 works again. Further, the capacitance of the third capacitor C7 is 2.2 μF, which can be used to filter high-frequency signals.

[0044] As shown Figure 3 In one embodiment, the power supply circuit 320 further includes a general diode D2. The anode of the general diode D2 is connected to the input end of the transformer T1, and the cathode of the general diode D2 is connected to the first end of the second resistor R8. It can be understood that the setting of the general diode D2 can ensure that the current at the input end of the transformer T1 flows unidirectionally to the three-port integrator U3, avoiding the situation of circuit element damage caused by current backflow.

[0045] The present disclosure also provides an LED lamp, including the soft-start LED circuit 10 according to any one of the above embodiments. In this embodiment, when the LED lamp adopts the soft-start LED circuit 10, the brightness of the LED lamp can be controlled by a switch and the current brightness can be memorized (the current brightness is lower than the brightness in the normal working state), so that the LED lamp can slowly increase from the current brightness when powered on next time until the brightness reaches the normal working state.

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

[0047] When the soft-start LED circuit 10 is powered on and the LED lamp is working, the output current of the isolation driver U1 can be switched to any current state through a switch. At this time, the soft-start LED circuit 10 memorizes the corresponding output current state, so that the user can enter the specified current state instantly when the LED lamp is powered on next time, and then the output current slowly rises. The period when the light changes from dark to bright can allow the human eye to adapt to the corresponding light state, thus realizing the function of slow lighting and avoiding sudden lighting.

[0048] The above embodiments only represent several implementation manners of the present disclosure, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the disclosed patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several deformations and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A slow-start LED circuit, characterized in that: include: Rectifier circuit, used to convert AC power into DC power; A transformer output circuit, used for receiving direct current and transforming the direct current and then outputting it to the lamp, comprising a direct current input circuit, a direct current output circuit, an isolation driver and a transformer, wherein the input end of the direct current input circuit is connected to the output end of the rectifier circuit, the output end of the direct current input circuit is electrically connected to the input end of the direct current output circuit through the transformer, the power generation end of the direct current input circuit is respectively connected to the power connection end of the isolation driver and the input end of the transformer, and the output end of the isolation driver is connected to the input end of the transformer; The detection control circuit comprises a power-on detection circuit and a power supply circuit, wherein the power-on detection circuit comprises a series resistor and a first resistor, wherein the first end of the series resistor is respectively connected to the input end of the rectifier circuit and the two power generation ends of the DC input circuit, the second end of the series resistor is connected to the first end of the first resistor, and the second end of the first resistor is grounded; the power supply circuit comprises a second resistor, a three-port integrator and a frequency modulator, wherein the first end of the first resistor is connected to the signal receiving end of the frequency modulator, the signal output end of the frequency modulator is connected to the control end of the isolation driver, the first end of the second resistor is connected to the input end of the transformer, the second end of the second resistor is connected to the input end of the three-port integrator, the ground end of the three-port integrator is grounded, and the output end of the three-port integrator is connected to the power supply end of the frequency modulator.

2. The slow-start LED circuit according to claim 1, characterized in that: The series resistor includes a third resistor, a fourth resistor and a fifth resistor. The first end of the first resistor is connected to two power generation ends of the DC input circuit through the fifth resistor, the fourth resistor and the third resistor in sequence.

3. The slow-start LED circuit according to claim 2, characterized in that: At least one of the third resistor, the fourth resistor, and the fifth resistor is a variable resistor.

4. The slow-start LED circuit according to claim 1, characterized in that: The power-on detection circuit further includes a first capacitor, wherein an upper half of the first capacitor is connected to a first end of the first resistor, and a lower half of the first capacitor is connected to a second end of the first resistor.

5. The slow-start LED circuit according to claim 1, characterized in that: The power supply circuit further includes a sixth resistor, and the signal output end of the frequency modulator is connected to the control end of the isolation driver through the sixth resistor.

6. The slow-start LED circuit according to claim 5, characterized in that: The sixth resistor is a variable resistor.

7. The slow-start LED circuit according to claim 1, characterized in that: The power supply circuit further includes a second capacitor, an upper end of the second capacitor is connected to the input end of the three-port integrator, and a lower end of the second capacitor is grounded.

8. The slow-start LED circuit according to claim 1, characterized in that: The power supply circuit further includes a third capacitor, an upper end of the third capacitor is connected to the output end of the three-port integrator, and a lower end of the third capacitor is grounded.

9. The slow-start LED circuit according to claim 1, characterized in that: The power supply circuit further includes a universal diode, an anode of the universal diode is connected to the input end of the transformer, and a cathode of the universal diode is connected to the first end of the second resistor.

10. An LED lamp, characterized in that: The invention comprises the slow-start LED circuit as described in any one of claims 1 to 9.

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