CN217486679U

CN217486679U - LED power supply starting sequential control circuit

Info

Publication number: CN217486679U
Application number: CN202221563243.2U
Authority: CN
Inventors: 陈耿圳
Original assignee: Zhuhai Shengchang Electronics Co ltd
Current assignee: Zhuhai Shengchang Electronics Co ltd
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2022-09-23
Anticipated expiration: 2032-06-20

Abstract

The utility model discloses a LED power starts sequential control circuit, including the PFC circuit, a power supply circuit, the step-down circuit, resistance R1-2, electric capacity C1-2 and switch tube Q1-2, external power source is connected with PFC circuit and step-down circuit's input respectively, the output of PFC circuit is connected with the LED lamp through power supply circuit, the output of step-down circuit inserts the PFC circuit, resistance R1, resistance R2 and switch tube Q2's input, resistance R2's the other end respectively with switch tube Q1's input, electric capacity C2's one end and switch tube Q2's control end are connected, switch tube Q2's output inserts power supply circuit, resistance R1's the other end is connected with switch tube Q1's control end through electric capacity C1, switch tube Q1's the output and electric capacity C2's the other end ground connection; adjusting parameters of a resistor R2 and a capacitor C2 so that the PFC circuit is started first and the power circuit is started again when the system is powered on; when the power is powered on next time, the resistor R1, the capacitor C1 and the switching tube Q1 discharge electricity on the capacitor C2 to the ground, so that the PFC circuit is started first, and the power supply circuit is started again.

Description

LED power supply starting sequential control circuit

Technical Field

The utility model relates to a power supply circuit and controller circuit field, in particular to LED power start-up sequential control circuit.

Background

With the continuous improvement of science and technology, the life quality of people becomes better and better, and the LEDs are installed in each household and outdoor illumination, so that the LED power supply market is developed vigorously, and the requirements on the LED power supply are higher and higher; most of the LED power supplies in the current market require a PFC (power factor correction) function so as to improve the power efficiency; grid voltages in north america are AC120V and AC277V, and are generally calculated by referring to the voltage boosted by PFC when designing an LED power transformer, and when the LED power transformer is used in AC120V, if PFC is not yet available, AC120V supplies power to the LED power, peak current is large when the LED power is started, so that the LED power is not protected; therefore, the PFC boost is ensured to be started firstly, and then the later-stage drive is started; therefore, it is necessary to develop a circuit for controlling the start-up timing of an LED power supply.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a LED power starts sequential control circuit.

The utility model discloses a technical scheme that its technical problem was solved to an embodiment adopted is: an LED power supply starting time sequence control circuit comprises a PFC circuit, a power circuit, a voltage reduction circuit, a resistor R1-2, a capacitor C1-2 and a switch tube Q1-2, wherein an external power supply is respectively connected with input ends of the PFC circuit and the voltage reduction circuit, an output end of the PFC circuit is connected with an LED lamp through the power circuit, an output end of the voltage reduction circuit is connected with input ends of the PFC circuit, the resistor R1, the resistor R2 and a switch tube Q2, the other end of the resistor R2 is respectively connected with an input end of the switch tube Q1, one end of the capacitor C2 and a control end of a switch tube Q2, an output end of the switch tube Q2 is connected with the power circuit, the other end of the resistor R1 is connected with a control end of the switch tube Q1 through the capacitor C1, and the output end of the switch tube Q1 and the other end of the capacitor C2 are grounded; adjusting parameters of a resistor R2 and a capacitor C2 so that the PFC circuit is started first and the power circuit is started again when the system is powered on; when the power is powered on next time, the resistor R1, the capacitor C1 and the switching tube Q1 discharge electricity on the capacitor C2 to the ground, so that the PFC circuit is started first, and the power supply circuit is started again.

Further, the PFC circuit includes a rectifier bridge DB1, a transformer T2, a power chip U2, a switch Q3, resistors R3-5, R10, R12-13, R12, diodes D12, and a capacitor EC 12, an input terminal of the rectifier bridge DB 12 is connected to an external power source, an output terminal of the rectifier bridge DB 12 is connected to an anode of the diode D12, one end of a first winding of the transformer T12, and one end of the resistor R12, another end of the resistor R12 is connected to the power chip U12 and one end of the resistor R12, a cathode of the diode D12 is connected to one end of the capacitor EC 12, a cathode of the diode D12, and the power circuit, an anode of the diode D12 is connected to another end of the first winding of the transformer T12 and an output terminal of the switch Q12, a control terminal of the switch Q12 is connected to the power chip U12, an input terminal of the switch Q12 is connected to one end of the power chip U12 and one end of the resistor R12, the other end of the resistor R12 is connected with one end of a power chip U2 and one end of a resistor R15 respectively, the VCC end of the power chip U2 is connected with the input end of a voltage reduction circuit, the resistor R2 and the switch tube Q2, one end of a second winding of a transformer T2 is connected with the power chip U2 through a resistor R4, and the other end of a second winding of a transformer T2, the other end of a capacitor EC1, the other end of a resistor R5, the other end of a resistor R13 and the other end of a resistor R15 are grounded.

Further, the LED power supply starting sequence control circuit further comprises a resistor R14 and a capacitor C4, wherein one end of the resistor R14 is connected with the power supply chip U2, and the other end of the resistor R3526 is grounded through the capacitor C4.

Further, the power supply circuit comprises a transformer T1, a power chip U1, resistors R7-9, R11 and a switching tube Q4, one end of a first winding of the transformer T1 is connected with the PFC circuit, the other end of the first winding of the transformer T1 is connected with one end of the switching tube Q4, one end of a second winding of the transformer T1 is connected with one end of the resistor R9 and the power chip U1 through a resistor R8, a control end of the switching tube Q4 is connected with the power chip U1 through a resistor R7, the other end of the switching tube Q4 is connected with one end of the resistor R11 and the power chip U1, the LED lamp is connected to a third winding of the transformer T1, and the other end of the resistor R9, the other end of the resistor R11 and the other end of the second winding of the transformer T1 are grounded.

Further, the LED power supply start timing control circuit further includes a resistor R6, a capacitor C5, and a diode D2, one end of the resistor R6 is connected to one end of the PFC circuit, one end of the capacitor C5, and one end of the first winding of the transformer T1, the other end of the resistor R6 is connected to the other end of the capacitor C5 and the cathode of the diode D2, and an anode of the diode D2 is connected to one end of the switching tube Q4 and the other end of the first winding of the transformer T1.

Further, the LED power supply starting sequence control circuit further comprises a resistor R16 and a capacitor C3, one end of the resistor R16 is connected with the power chip U1, and the other end of the resistor R16 is grounded through the capacitor C3.

Further, the LED power supply starting sequence control circuit further comprises a diode D3 and a capacitor EC3, wherein the anode of the diode D3 is connected with one end of the third winding of the transformer T1, the cathode of the diode D3 is respectively connected with one end of the LED lamp and one end of the capacitor EC3, and the other end of the capacitor EC3 is respectively connected with the other end of the third winding of the transformer T3 and the other end of the LED lamp.

The utility model has the advantages that: an LED power supply starting time sequence control circuit comprises a PFC circuit, a power circuit, a voltage reduction circuit, a resistor R1-2, a capacitor C1-2 and a switch tube Q1-2, wherein an external power supply is respectively connected with input ends of the PFC circuit and the voltage reduction circuit, an output end of the PFC circuit is connected with an LED lamp through the power circuit, an output end of the voltage reduction circuit is connected with input ends of the PFC circuit, the resistor R1, the resistor R2 and a switch tube Q2, the other end of the resistor R2 is respectively connected with an input end of the switch tube Q1, one end of the capacitor C2 and a control end of a switch tube Q2, an output end of the switch tube Q2 is connected with the power circuit, the other end of the resistor R1 is connected with a control end of the switch tube Q1 through the capacitor C1, and the output end of the switch tube Q1 and the other end of the capacitor C2 are grounded; adjusting parameters of a resistor R2 and a capacitor C2 so that the PFC circuit is started first and the power circuit is started again when the system is powered on; when the power supply is powered on next time, the resistor R1, the capacitor C1 and the switch tube Q1 discharge electricity on the capacitor C2 to the ground, so that the PFC circuit is started first, and the power supply circuit is started again.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic block diagram of an LED power supply start-up sequence control circuit;

fig. 2 is a circuit diagram of an LED power supply start timing control circuit.

Detailed Description

This section will describe in detail the embodiments of the present invention, preferred embodiments of the present invention are shown in the attached drawings, which are used to supplement the description of the text part of the specification with figures, so that one can intuitively and vividly understand each technical feature and the whole technical solution of the present invention, but they cannot be understood as the limitation of the protection scope of the present invention.

In the description of the present invention, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as excluding the number, and the terms greater than, less than, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise explicitly defined, the terms "set," "mounted," "connected," and the like are to be understood in a broad sense, and may be directly connected or indirectly connected through an intermediate medium, for example; can be fixedly connected, can also be detachably connected and can also be integrally formed; may be a mechanical connection; either as communication within the two elements or as an interactive relationship of the two elements. The technical skill in the art can reasonably determine the specific meaning of the above words in the present invention by combining the specific contents of the technical solution.

Referring to fig. 1 to 2, an LED power supply start timing control circuit includes a PFC circuit, a power supply circuit, a voltage dropping circuit, a resistor R1-2, a capacitor C1-2 and a switch tube Q1-2, an external power supply is connected to input terminals of the PFC circuit and the voltage dropping circuit, an output terminal of the PFC circuit is connected to an LED lamp through the power supply circuit, an output terminal of the voltage dropping circuit is connected to input terminals of the PFC circuit, the resistor R1, the resistor R2 and the switch tube Q2, the other terminal of the resistor R2 is connected to an input terminal of the switch tube Q1, one terminal of the capacitor C2 and a control terminal of the switch tube Q2, an output terminal of the switch tube Q2 is connected to the power supply circuit, the other terminal of the resistor R1 is connected to a control terminal of the switch tube Q1 through the capacitor C1, and the output terminal of the switch tube Q1 and the other terminal of the capacitor C2 are grounded; adjusting parameters of a resistor R2 and a capacitor C2 so that the PFC circuit is started first and the power circuit is started again when the system is powered on; when the power is powered on next time, the resistor R1, the capacitor C1 and the switching tube Q1 discharge electricity on the capacitor C2 to the ground, so that the PFC circuit is started first, and the power supply circuit is started again.

The PFC circuit comprises a rectifier bridge DB1, a transformer T2, a power chip U2, a switch tube Q3, resistors R3-5, R10, R12-13, R12, diodes D12, D12 and a capacitor EC 12, wherein the input end of the rectifier bridge DB 12 is connected with an external power supply, the output end of the rectifier bridge DB 12 is respectively connected with the anode of the diode D12, one end of a first winding of the transformer T12 and one end of the resistor R12, the other end of the resistor R12 is respectively connected with the power chip U12 and one end of the resistor R12, the cathode of the diode D12 is respectively connected with one end of the capacitor EC 12, the cathode of the diode D12 and the power circuit, the anode of the diode D12 is respectively connected with the other end of the first winding of the transformer T12 and the output end of the switch tube Q12, the control end of the switch tube Q12 is connected with the power chip U12, the input end of the switch tube Q12 is respectively connected with the power chip 12 and one end of the resistor R12, the other end of the resistor R12 is connected with one end of a power chip U2 and one end of a resistor R15 respectively, the VCC end of the power chip U2 is connected with the input ends of the step-down circuit, the resistor R2 and the switch tube Q2, one end of the second winding of the transformer T2 is connected with the power chip U2 through the resistor R4, and the other end of the second winding of the transformer T2, the other end of the capacitor EC1, the other end of the resistor R5, the other end of the resistor R13 and the other end of the resistor R15 are grounded.

The LED power supply starting sequence control circuit further comprises a resistor R14 and a capacitor C4, wherein one end of the resistor R14 is connected with a power supply chip U2, and the other end of the resistor R2 is grounded through the capacitor C4.

The power supply circuit comprises a transformer T1, a power chip U1, a resistor R7-9, a resistor R11 and a switch tube Q4, one end of a first winding of the transformer T1 is connected with the PFC circuit, the other end of the first winding of the transformer T1 is connected with one end of the switch tube Q4, one end of a second winding of the transformer T1 is connected with one end of the resistor R9 and the power chip U1 through a resistor R8, a control end of the switch tube Q4 is connected with the power chip U1 through a resistor R7, the other end of the switch tube Q4 is respectively connected with one end of a resistor R11 and the power chip U1, the LED lamp is connected to a third winding of the transformer T1, and the other end of the resistor R9, the other end of the resistor R11 and the other end of the second winding of the transformer T1 are grounded.

The LED power supply starting sequence control circuit further comprises a resistor R6, a capacitor C5 and a diode D2, one end of the resistor R6 is connected with the PFC circuit, one end of the capacitor C5 and one end of a first winding of a transformer T1, the other end of the resistor R6 is connected with the other end of the capacitor C5 and the cathode of the diode D2, and the anode of the diode D2 is connected with one end of a switching tube Q4 and the other end of the first winding of the transformer T1.

The LED power supply starting sequence control circuit further comprises a resistor R16 and a capacitor C3, one end of the resistor R16 is connected with a power supply chip U1, and the other end of the resistor R16 is grounded through a capacitor C3.

The LED power supply starting time sequence control circuit further comprises a diode D3 and a capacitor EC3, wherein the anode of the diode D3 is connected with one end of a third winding of a transformer T1, the cathode of the diode D3 is respectively connected with one end of an LED lamp and one end of a capacitor EC3, and the other end of the capacitor EC3 is respectively connected with the other end of the third winding of the transformer T3 and the other end of the LED lamp.

The working principle of the utility model is as follows:

when the system is powered on, L, N is connected to a voltage reducing circuit through terminals, the voltage reducing circuit outputs a voltage terminal VDD and a ground terminal GND to supply power to a power chip U1 and a power chip U2, then L, N is connected to two ends of an AC input of a rectifier bridge DB1, the AC input is rectified by the rectifier bridge DB1 and then connected to an anode of a diode D1, a capacitor EC1 is precharged, the AC input is connected to a first winding of a transformer T2 and a pin 2 of a power chip U2, after an input voltage is detected by a resistor R10 and a resistor R13, a pin 7 of the power chip U2 outputs a driving signal to conduct a switch tube Q3 through a resistor R3 to chop the voltage on the transformer T2, the chopped voltage charges the capacitor EC1 through a diode D4, the voltage on the capacitor EC1 is fed back to a pin 5 of the power chip U2 through a resistor R12 and a resistor R15, and the resistor R5 converts the current flowing through a switch tube Q3 into a voltage signal to be fed back to a pin 6 of the power chip U2, the proportional output signal of the second winding of the transformer T2 is connected to pin 1 of the power chip U2 through a resistor R4 for detection, and the resistor R14 and a capacitor C4 compensate the power chip U2.

The switching transistor Q2 is preferably an NPN transistor, the voltage terminal VDD is connected to the collector of the NPN transistor Q2 and the resistor R2, the capacitor C2 is charged through the resistor R2, the capacitor C2 is connected to the base of the NPN transistor Q2, the emitter of the NPN transistor Q2 outputs a voltage VCC to the 6 th leg of the power chip U1, when the capacitor C2 is charged to the start threshold voltage of the power chip U1, the 5 th leg of the power chip U1 outputs a driving signal to drive the NMOS transistor Q7 through the resistor R7, the NMOS transistor Q7 chops the first winding of the transformer T7, the resistor R7 converts the current flowing through the NMOS transistor Q7 into a voltage signal and feeds the voltage signal back to the 4 th leg of the power chip U7, the second winding of the transformer T7 outputs a feedback signal which is connected to the 2 nd leg of the power chip U7 through the resistor R7 and the resistor R7, the resistor R7 and the capacitor C7 compensate the winding of the power chip U7, and the second winding of the transformer T7 outputs a rectified voltage through the rectifying diode 7 and the rectifying diode EC 7 for rectifying diode 7. Connecting voltage to a voltage terminal V + and a ground terminal V-, wherein two ends of the voltage terminal V + and the ground terminal V-can be connected with an LED lamp, and the LED lamp is lighted at the moment; the diode D2, the resistor R6 and the capacitor C5 clamp the voltage on the drain of the NMOS transistor Q4 within a safe voltage range; the resistor R2 and the capacitor C2 are set to appropriate parameters, so that the power chip U1 can be restarted after the power chip U2 is started, and when the LED power supply is powered off and is powered on again immediately, the voltage terminal VDD is conducted to the NPN triode Q1 through the resistor R1 and the capacitor C1, the power on the capacitor C2 is discharged to the ground through the NPN triode Q1, and the latter circuit is prevented from being started when the boost of the PFC circuit is not yet up.

The embodiment of the utility model provides an advantage lies in: by setting the parameters of the resistor R2 and the capacitor C2, when the system is powered on, the power chip U2 is started first, and then the power chip U1 is started again, so that the LED power supply is prevented from being protected when being powered on; and when the power is powered on next time, the resistor R1, the capacitor C1 and the NPN triode Q1 discharge the electricity on the capacitor C2 to the ground, so that the latter circuit is prevented from being started when the boost of the PFC circuit is not up.

The present invention is not limited to the above embodiments, and equivalent modifications and substitutions may be made by those skilled in the art without departing from the spirit of the present invention, and the equivalents and substitutions are intended to be included within the scope of the present invention as defined by the appended claims.

Claims

1. The utility model provides a LED power start-up sequential control circuit which characterized in that: the LED lamp comprises a PFC circuit, a power supply circuit, a voltage reduction circuit, a resistor R1-2, a capacitor C1-2 and a switch tube Q1-2, wherein an external power supply is respectively connected with input ends of the PFC circuit and the voltage reduction circuit, the output end of the PFC circuit is connected with an LED lamp through the power supply circuit, the output end of the voltage reduction circuit is connected with input ends of the PFC circuit, the resistor R1, the resistor R2 and the switch tube Q2, the other end of the resistor R2 is respectively connected with the input end of the switch tube Q1, one end of the capacitor C2 and the control end of the switch tube Q2, the output end of the switch tube Q2 is connected with the power supply circuit, the other end of the resistor R1 is connected with the control end of the switch tube Q1 through the capacitor C1, and the output end of the switch tube Q1 and the other end of the capacitor C2 are grounded; adjusting parameters of a resistor R2 and a capacitor C2 so that the PFC circuit is started first and the power circuit is started again when the system is powered on; when the power is powered on next time, the resistor R1, the capacitor C1 and the switching tube Q1 discharge electricity on the capacitor C2 to the ground, so that the PFC circuit is started first, and the power supply circuit is started again.

2. The LED power supply start-up timing control circuit of claim 1, wherein: the PFC circuit comprises a rectifier bridge DB1, a transformer T2, a power chip U2, a switching tube Q3, resistors R3-5, R10, R12-13, R12, diodes D12, D12 and a capacitor EC 12, wherein the input end of the rectifier bridge DB 12 is connected with an external power supply, the output end of the rectifier bridge DB 12 is respectively connected with the anode of the diode D12, one end of a first winding of the transformer T12 and one end of the resistor R12, the other end of the resistor R12 is respectively connected with the power chip U12 and one end of the resistor R12, the cathode of the diode D12 is respectively connected with one end of the capacitor EC 12, the cathode of the diode D12 and the power circuit, the anode of the diode D12 is respectively connected with the other end of the first winding of the transformer T12 and the output end of the switching tube Q12, the control end of the switching tube Q12 is connected with the power chip U12, the input end of the switching tube Q12 is respectively connected with one end of the power supply U12 and one end of the resistor R12, the other end of the resistor R12 is connected with one end of a power chip U2 and one end of a resistor R15 respectively, the VCC end of the power chip U2 is connected with the input ends of the step-down circuit, the resistor R2 and the switch tube Q2, one end of the second winding of the transformer T2 is connected with the power chip U2 through the resistor R4, and the other end of the second winding of the transformer T2, the other end of the capacitor EC1, the other end of the resistor R5, the other end of the resistor R13 and the other end of the resistor R15 are grounded.

3. The LED power supply start-up timing control circuit of claim 2, wherein: the power supply further comprises a resistor R14 and a capacitor C4, wherein one end of the resistor R14 is connected with the power supply chip U2, and the other end of the resistor R14 is grounded through the capacitor C4.

4. The LED power supply start-up timing control circuit of claim 1, wherein: the power supply circuit comprises a transformer T1, a power supply chip U1, resistors R7-9, a resistor R11 and a switch tube Q4, one end of a first winding of the transformer T1 is connected with the PFC circuit, the other end of the first winding of the transformer T1 is connected with one end of the switch tube Q4, one end of a second winding of the transformer T1 is connected with one end of the resistor R9 and the power supply chip U1 through a resistor R8, a control end of the switch tube Q4 is connected with the power supply chip U1 through a resistor R7, the other end of the switch tube Q4 is respectively connected with one end of the resistor R11 and the power supply chip U1, an LED lamp is connected to a third winding of the transformer T1, and the other end of the resistor R9, the other end of the resistor R11 and the other end of the second winding of the transformer T1 are grounded.

5. The LED power supply start-up timing control circuit according to claim 4, wherein: the high-voltage switch further comprises a resistor R6, a capacitor C5 and a diode D2, wherein one end of the resistor R6 is connected with one end of the PFC circuit, one end of the capacitor C5 and one end of a first winding of a transformer T1, the other end of the resistor R6 is connected with the other end of the capacitor C5 and a cathode of the diode D2, and an anode of the diode D2 is connected with one end of the switching tube Q4 and the other end of the first winding of the transformer T1.

6. The LED power supply start-up timing control circuit according to claim 4, wherein: the power supply further comprises a resistor R16 and a capacitor C3, one end of the resistor R16 is connected with the power supply chip U1, and the other end of the resistor R16 is grounded through the capacitor C3.

7. The LED power supply start-up timing control circuit according to claim 4, wherein: the LED lamp further comprises a diode D3 and a capacitor EC3, wherein the anode of the diode D3 is connected with one end of the third winding of the transformer T1, the cathode of the diode D3 is respectively connected with one end of the LED lamp and one end of the capacitor EC3, and the other end of the capacitor EC3 is respectively connected with the other end of the third winding of the transformer T3 and the other end of the LED lamp.