CN216122951U

CN216122951U - Multi-input LED constant current driving circuit

Info

Publication number: CN216122951U
Application number: CN202122466806.8U
Authority: CN
Inventors: 成海斌; 谢祖华; 苏宗才
Original assignee: Shenzhen Civil Explosion Photoelectric Co ltd
Current assignee: Shenzhen Civil Explosion Photoelectric Co ltd
Priority date: 2021-10-13
Filing date: 2021-10-13
Publication date: 2022-03-22
Anticipated expiration: 2031-10-13

Abstract

The utility model discloses a multi-path input LED constant current driving circuit which comprises n power supply dimming modules, wherein the output end of each power supply dimming module is connected to a trunk circuit, the trunk circuit is respectively connected with the input end of a primary winding of a transformer and the phase detection end of a flyback control module, the output end of the primary winding is connected with the signal output end of the flyback control module, a secondary winding of the transformer is connected with the input end of a load access channel, the output end of a secondary first winding of the transformer is connected with the power supply input end of the flyback control module, and the output end of each power supply dimming module is connected with the current detection end of the flyback control module through an independent current feedback module. The utility model has the beneficial effects that: different alternating current power supplies are provided with independent power dimming modules, and under the condition of multi-path power supply input, the LED driving circuit can be compatible with various dimming modes by selecting different types of dimming control chips as controllers of the flyback control module 5.

Description

Multi-input LED constant current driving circuit

Technical Field

The utility model relates to the technical field of LED driving, in particular to a multi-input LED constant current driving circuit.

Background

Currently, the mainstream LED driving mainly includes the following power-adjusting and light-adjusting modes: thyristor dimming, linear dimming, PWM dimming, remote dimming, and step dimming. No matter which dimming mode is adopted, the power adjustment operation can only be carried out on a single power supply, and the dimming mode cannot be compatible with multiple dimming modes.

SUMMERY OF THE UTILITY MODEL

Aiming at the problems, the utility model provides a multi-input LED constant current driving circuit, which mainly solves the problem that the existing LED constant current driving circuit cannot be compatible with various dimming modes.

In order to solve the technical problems, the technical scheme of the utility model is as follows:

the utility model provides a multiple entry LED constant current drive circuit, includes n power dimming module, n is greater than or equal to 2, every the output of power dimming module is connected to a main road, the main road is connected with the input of the primary winding of transformer respectively to and the phase detection end of flyback control module, the output of primary winding with flyback control module's signal output part is connected, the secondary second winding of transformer is connected with the input of load access channel, the output of the secondary first winding of transformer with flyback control module's power input end is connected, and every power dimming module's output pass through independent current feedback module with flyback control module's current detection end is connected.

In some embodiments, each of the power dimming modules is matched with an independent ac power source.

In some embodiments, the ac power source is mains power.

In some embodiments, the power dimming module includes a dimmer, a lightning protection unit, an EMI filter unit, and a rectifier unit, which are sequentially connected, an input end of the dimmer is used to be connected to the live wire of the ac power supply, and an output end of the rectifier unit is connected to an input end of the primary winding of the transformer and a phase detection end of the flyback control module.

In some embodiments, the dimmer is a tangential dimmer control.

The utility model has the beneficial effects that: through setting up independent power dimming module for different alternating current power supply, under the circumstances of multichannel power input, can realize that LED drive circuit is compatible multiple mode of adjusting luminance through selecting for use the control chip that adjusts luminance of different grade type as the controller of flyback control module.

Drawings

Fig. 1 is a schematic structural diagram of a multi-input LED constant current driving circuit according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a multi-input LED constant current driving circuit disclosed in the second embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the following detailed description of the present invention is provided with reference to the accompanying drawings and detailed description. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings.

Example one

The embodiment provides a multi-input LED constant current driving circuit, as shown in fig. 1, the multi-input LED constant current driving circuit includes n power dimming modules, n is greater than or equal to 2, an output end of each power dimming module is connected to a main line, the main line is connected to an input end of a primary winding of a transformer 4 and a phase detection end of a flyback control module 5, an output end of the primary winding is connected to a signal output end of the flyback control module 5, a secondary winding of the transformer 4 is connected to an input end of a load access channel 6, an output end of a secondary winding of the transformer 4 is connected to a power input end of the flyback control module 5, and an output end of each power dimming module is connected to a current detection end of the flyback control module 5 through an independent current feedback module 7. Each power supply dimming module is matched with an independent alternating current power supply, and optionally, the alternating current power supply is mains supply. The dimmer described above may be any form of dimming device, for example, the dimmer is a tangential dimmer control.

In this embodiment, the number of the power dimming modules is n, each power dimming module comprises a dimmer, a lightning protection unit, an EMI filter unit and a rectifier unit which are connected in sequence, an input end of the dimmer is connected to a live wire of an ac power supply, and an output end of the rectifier unit is connected to an input end of a primary winding of a transformer and a phase detection end of a flyback control module. Taking the driving circuit shown in fig. 1 as an example, the power dimming module 1 includes a dimmer 101, a lightning protection unit 102, an EMI filter unit 103, and a rectifying unit 104, and the power dimming module 2 includes a dimmer 201, a lightning protection unit 202, an EMI filter unit 203, and a rectifying unit 204, until the power dimming module n includes a dimmer n01, a lightning protection unit n02, an EMI filter unit n03, and a rectifying unit n 04. The power dimming module 1, the power dimming module 2, and the power dimming module n are provided with an ac power supply L1, an ac power supply L2, and an ac power supply Ln, which are independent of each other. For ease of representation, the main line is not represented by a single line in fig. 1, and the representation of the main line also does not represent that the output ends of each of the power dimming modules are all connected to the same physical main line, and is only used for expressing that the primary winding of the transformer 4 is affected by the output end of each of the power dimming modules, and those skilled in the art should know the working principle thereof, and details thereof are not repeated herein.

Taking the power dimming module 1 as an example: the lightning protection unit 102 is used for absorbing surge lightning strike signals generated at a commercial power end, reducing the surge lightning strike signals to be output within a range which can be borne by a rear-stage circuit, ensuring that the rear-stage circuit is not damaged, and improving the stability of the system. And the EMI filtering unit 103 is used for receiving the signal output by the lightning protection unit, filtering and outputting the signal to meet the requirement of electromagnetic compatibility, so that the index of the electromagnetic compatibility is within a qualified level. And the rectifying unit 104 receives the alternating current signal output by the EMI filtering unit, rectifies the alternating current signal into a direct current signal and outputs the direct current signal.

In the embodiment, the independent power dimming modules are arranged for different alternating current power supplies, and under the condition of multi-path power supply input, the dimming control chips of different types can be selected as the controller of the flyback control module 5, so that the LED driving circuit is compatible with various dimming modes.

Example two

In this embodiment, the first embodiment is taken as a basis, and the tangential dimming control main chip is taken as a controller of the flyback control module 5 to perform the explanation of the present invention.

As shown in fig. 1 and 2, the AC + terminal of the rectifying unit of the power dimming module 1 is connected to the input terminal of the primary winding of the transformer 4, the output terminal of the primary winding is connected to the signal output terminal of the flyback control module 5, the high-voltage terminal HV + is connected to the AC + terminal of the rectifying unit of the power dimming module 1, on the line, the AC + terminal of the rectifying unit of the power dimming module 1 is grounded through the capacitor Cbuck, and the AC-terminal of the rectifying unit of the power dimming module 1 is grounded. Two ends of a primary winding of the transformer 4 are connected with a resistor R0 and a diode D0 which are connected in series, two ends of the resistor R0 are connected with a capacitor C0 in parallel, and the anode of the diode D0 is connected with the signal output end of the flyback control module 5. An AC + end of a rectifying unit of the power dimming module 2 is connected with an anode of a diode D1, a cathode of a diode D1 is connected with a primary winding of the transformer 4, an AC-end of the rectifying unit of the power dimming module 2 is grounded, an AC + end of the rectifying unit of the power dimming module 2 is connected to a current feedback module 7, the current feedback module 7 comprises a resistor RH1, the other end of the resistor RH1 is connected with a G electrode of a Mos transistor QS1, the D electrode of the Mos transistor QS1 is connected with an Rs1 and finally connected to a current detection end of the flyback control module 5, the G electrode of the Mos transistor QS1 is also connected with a resistor Rz1 and a voltage regulator Zp1 in parallel, and an anode of the voltage regulator Zp1 is connected with the S electrode of the Mos transistor QS 1. The AC + end of a rectifying unit of the power supply dimming module n is connected with the anode of a diode Dn, the cathode of a diode D1 is connected with a primary winding of a transformer 4, the AC-end of the rectifying unit of the power supply dimming module n is grounded, the AC + end of the rectifying unit of the power supply dimming module n is connected with a further independent current feedback module 7, the current feedback module 7 comprises a resistor RHn, the other end of the resistor RHn is connected with the G electrode of a Mos transistor QSn, the D electrode and Rsn of the Mos transistor QSn are connected with a current detection end which is finally connected into a flyback control module 5, the G electrode of the Mos transistor QSn is also connected with a resistor Rzn and a voltage regulator tube Zpn in parallel, and the anode of the voltage regulator tube Zpn is connected with the S electrode of the Mos transistor QSn. Finally, the current detection end of the flyback control module 5 is further connected with a resistor Rs, and the other end of the resistor Rs is grounded.

The flyback control module 5 outputs PWM signals according to a preset rule after receiving pulse signals, in each PWM period, a high level period drives a main circuit transistor to be switched on and stores energy through a coil of the transformer 4, a low level period transistor is switched off, the energy of a primary coil of the transformer is rectified through a Ds diode according to the principle of electromagnetic induction, the energy is output after CE filtering, and the requirement of linear change of output current is met by changing the on-off duty ratio of the transistor.

The output end of the secondary side first winding of the transformer 4 is connected with the anode of the diode Dv, the cathode of the diode Dv is connected with the power input end of the flyback control module 5, the cathode of the diode Dv is also connected with the power supply VDD, and the cathode of the diode Dv is grounded through the capacitor Cv.

One end of a secondary side second winding of the transformer 4 is connected with the anode of a diode Ds, the cathode of the diode Ds is connected with the LED + end of the load access channel 6, the other end of the secondary side second winding is connected with the LED-end of the cathode access channel 6, and a filter CE is arranged between the LED + end and the LED-end of the load access channel 6.

The principle of the multiple input is as follows:

the mains supply is connected to the line through L1 and N1, and is rectified into direct-current voltage through the lightning protection unit 102, the EMI filter unit 103 and the rectifier unit 104 to supply power to the VDD terminal of the flyback control module 5. At this time, due to the one-way conduction principle of the diode D1, the RH1 resistor has no voltage, the G electrode of the Mos transistor QS1 has no level, the Mos transistor QS1 is turned off, and the current detection end of the flyback control module 5 is supplied with a potential through the resistor Rs to generate the fixed constant current 1.

The mains supply is connected to a line through L2 and N1 (or a dimmer), and is rectified into a direct-current voltage through the lightning protection unit 202, the EMI filter unit 203 and the rectifier unit 204, and then the direct-current voltage is supplied to the VDD of the flyback control module 5 through the diode D1. At this time, because of the resistor RH1 and the resistor Rz1, the voltage regulator tube Zp1 generates a continuous high level, so that the Mos transistor QS1 is in saturated conduction, at this time, the resistance value of the resistor RS1 and the resistor RS in parallel connection becomes small, the potential of the current detection end of the flyback control module 5 becomes low, and a new fixed current 2 is generated.

Similarly, the commercial power is connected to the line through different inputs Ln and Nn, and is rectified into direct-current voltage through the lightning protection unit n02, the EMI filter unit n03 and the rectifier unit n04, and the direct-current voltage is supplied to the VDD of the flyback control module 5 through Dn. At this time, because of the resistor RHn and the resistor Rzn, the voltage regulator tube Zpn generates a continuous high level, so that the Mos transistor QSn is in saturated conduction, at this time, the parallel resistance of RSn and RS becomes small, the potential of the current detection end of the flyback control unit becomes low, and a new fixed current n is generated.

Because the flyback control module 5 for tangential dimming control is adopted in the embodiment, a tangential dimming controller (namely a dimmer) is connected in front of any group of commercial power L connected to the driving circuit, so that the tangential deep dimming of the current group can be further realized, and the stepless control of power can be further realized.

Optionally, a plurality of wall switches are introduced to the plurality of L1, L2.. Ln, so that the requirement of multi-power fixed dimming of the lamp can be met.

Optionally, the inductive control of the current group can be realized by connecting an inductive switch before any group of L is accessed.

Optionally, the main control chip is changed into linear dimming, PWM dimming and the main control IC with multi-section dimming power can also realize 0-10V of multi-power input gears, PWM dimming, switch dimming and DALI wired intelligent control, 2.4G, wifi and other wireless control requirements, and the effective combination of fixed illumination and intelligent illumination is realized.

The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention accordingly, and not to limit the protection scope of the present invention accordingly. All equivalent changes or modifications made in accordance with the spirit of the present disclosure are intended to be covered by the scope of the present disclosure.

Claims

1. The multi-input LED constant-current driving circuit is characterized by comprising n power supply dimming modules, wherein n is more than or equal to 2, the output end of each power supply dimming module is connected to a main line, the main line is respectively connected with the input end of a primary winding of a transformer and the phase detection end of a flyback control module, the output end of the primary winding is connected with the signal output end of the flyback control module, a secondary winding of the transformer is connected with the input end of a load access channel, the output end of a secondary winding of the transformer is connected with the power supply input end of the flyback control module, and the output end of each power supply dimming module is connected with the current detection end of the flyback control module through an independent current feedback module.

2. The multi-input LED constant current driving circuit as claimed in claim 1, wherein each power dimming module is matched with an independent AC power supply.

3. The multi-input LED constant current driving circuit as claimed in claim 2, wherein the AC power supply is mains power.

4. The multi-input LED constant current driving circuit as claimed in claim 3, wherein the power dimming module comprises a dimmer, a lightning protection unit, an EMI filtering unit and a rectifying unit connected in sequence, an input end of the dimmer is used for being connected with a live wire of the AC power supply, and an output end of the rectifying unit is connected with an input end of a primary winding of the transformer and a phase detection end of the flyback control module.

5. The multi-input LED constant current driving circuit according to claim 4, wherein the dimmer is a tangential dimming controller.