CN111405705A

CN111405705A - Dimming L ED controller and output short-circuit protection method

Info

Publication number: CN111405705A
Application number: CN202010220053.XA
Authority: CN
Inventors: 俞剑峰; 赵鹏远; 王科
Original assignee: Ningbo Self Electronics Co Ltd
Current assignee: Ningbo Self Electronics Co Ltd
Priority date: 2020-03-25
Filing date: 2020-03-25
Publication date: 2020-07-10
Anticipated expiration: 2040-03-25
Also published as: CN111405705B

Abstract

The invention discloses a dimming L ED controller and an output short-circuit protection method, wherein the controller comprises a power supply positive input end, a power supply negative input end, a power supply module connected with the power supply positive input end, a control module connected with the power supply module, a switch module connected with a signal output end of the control module and used for driving an external load, and a dimming L ED controller further comprises a short-circuit protection module for collecting an electric signal of the external load negative, the control module comprises a signal receiving end connected with the short-circuit protection module, and the control module controls the working state of the switch module according to the electric signal output to the switch module and the electric signal received from the short-circuit protection module.

Description

Dimming L ED controller and output short-circuit protection method

Technical Field

The invention relates to power supply equipment, in particular to a dimming L ED controller and an output short-circuit protection method.

Background

Under the background of energy saving and environmental protection, a L ED lamp is increasingly applied to the field of household and commercial illumination because of high light emitting efficiency and good light condensing performance, the current adjustable L ED lamp controllers on the market mainly comprise two types, one type is a controller without short-circuit protection, although the function is not influenced, a high current caused under the condition of circuit short circuit can burn out a rear-stage power device and the like instantly, and the other type is a controller with a higher rated current, so that the current flowing through a power supply in the short circuit process is smaller than the rated current of the rear-stage power device, but the realization cost is higher and certain local occurrence is realized.

Disclosure of Invention

In view of the above, the present invention provides a dimming L ED controller to solve the above technical problems.

The utility model provides a L ED controller adjusts luminance, includes the anodal input of power, power negative pole input, connects the power module of the anodal input of power connects power module's control module and connection control module's signal output part is used for driving external load's switch module, L ED controller adjusts luminance is still including gathering the short-circuit protection module of the signal of telecommunication of external load negative pole, control module is including connecting short-circuit protection module's signal reception end, control module gives according to the output switch module's the signal of telecommunication and receive come from the signal of telecommunication control that short-circuit protection module gathered switch module's operating condition.

Preferably, the short-circuit protection module includes a first resistor R1, a second resistor R2, and a voltage stabilizing unit, wherein an anode of the voltage stabilizing unit is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to the signal receiving end of the control module, one end of the second resistor R2 is connected to the signal receiving end of the control module, and the other end of the second resistor R2 is connected to the negative input end of the power supply.

Preferably, the switching module adopts a MOS transistor Q1 or a triode.

Preferably, the gate of the MOS transistor Q1 is connected to the signal output terminal of the control module, the drain is connected to the negative electrode of the load, and the source is connected to the negative electrode input terminal of the power supply.

Preferably, the voltage stabilizing unit comprises a voltage stabilizing tube D1.

Preferably, the anode of the voltage regulator tube D1 is connected to the first resistor R1, and the cathode is connected to the negative electrode of the external load.

Preferably, the voltage stabilizing unit comprises a T L431Q 2, a resistor R3 and a resistor R4, wherein an anode of the T L431Q 2 is connected with the first resistor R1, a cathode of the T L Q2 is connected with a negative electrode of the external load, a reference terminal of the T L Q2 is simultaneously connected with one end of the resistor R3 and one end of the resistor R4, the other end of the resistor R3 is connected with an anode of the T L431Q 2, and the other end of the resistor R4 is connected with a cathode of the T L431Q 2.

The invention provides an output short-circuit protection method for a dimming L ED controller, which adopts the dimming L ED controller and comprises the following steps:

001. after the dimming L ED controller is connected with a power supply and a load, the power supply is powered on to work, and the switch module is initialized and closed;

002. the control module controls the switch module to be started, an external load normally works, at the moment, the output of the control module to the switch module is at a high level, and the signal receiving end of the control module is at a low level;

003. when the external load is short-circuited, the voltage of a signal receiving end of the control module is instantly changed into high level, and when the voltage output by the control module to the switch module and the signal receiving end is high level, the control module closes the switch module for a time t;

004. and the control module reopens the switch module, the external load is normal, the step 002 is carried out, and the step 003 is carried out when the external load is short-circuited.

Preferably, 0.5 s.ltoreq.t.ltoreq.3 s.

The invention has the technical effects that:

the dimming L ED controller and the output short-circuit protection method thereof can accurately and effectively protect the controller when the load is in short circuit, and have the advantages of simple structure, low cost and small energy loss.

Drawings

Embodiments of the invention are described below with reference to the accompanying drawings, in which:

fig. 1 is a block diagram of the structure of a dimming L ED controller according to the present invention.

Fig. 2 is a circuit schematic diagram of a dimming L ED controller according to an embodiment.

Fig. 3 is a circuit schematic diagram of a dimming L ED controller according to another embodiment.

Fig. 4 is a block flow diagram of an output short-circuit protection method of the dimming L ED controller of fig. 1.

Detailed Description

Specific embodiments of the present invention will be described in further detail below based on the drawings. It should be understood that the description herein of embodiments of the invention is not intended to limit the scope of the invention.

As shown in fig. 1 and 2, the dimming L ED controller of the present embodiment includes a positive power input terminal 100, a negative power input terminal 200, a power supply module 300 connected to the positive power input terminal 100, a control module 400 connected to the power supply module 300, and a switch module 500 connected to a signal output terminal of the control module 400 and used for driving an external load 700.

The power supply positive input terminal 100 and the power supply negative input terminal 200 are used for connecting a power supply, the power supply module 300 and the control module 400 may adopt an existing circuit, and the control module 400 generally adopts a Micro Controller Unit (MCU).

The switch module 500 is used for driving an external load 700, the external load 700 is mainly an L ED lamp, in the embodiment, the switch module 500 adopts an MOS tube Q1, the grid electrode of the MOS tube Q1 is connected with the signal output end of the control module 400, the drain electrode is connected with the negative electrode of the load, the source electrode is connected with the negative electrode input end 200 of the power supply, and under the conduction voltage drop of the MOS tube (field effect tube), the conduction resistance is small, the grid electrode does not need current for driving, the loss is small, the driving circuit is simple, a self-contained protection diode is provided, the thermal resistance is good, and in another embodiment, the switch module 500 adopts a triode.

The dimming L ED controller of this embodiment further includes a short-circuit protection module 600 for collecting an electrical signal of the negative electrode of the external load 700, the control module 400 includes a signal receiving terminal connected to the short-circuit protection module 600, and the control module 400 controls the operating state of the switch module 500 according to the electrical signal output to the switch module 500 and the electrical signal received from the short-circuit protection module 600, so that when the external load 700 is short-circuited, the voltage signal of the signal receiving terminal of the control module 400 changes, and the control module 400 generates a signal for turning off the switch module 500, thereby achieving the purpose of protecting the switch module 500, specifically, obtains a control signal according to a comparison between the electrical signal output to the switch module 500 and the electrical signal received from the short-circuit protection module 600.

The short-circuit protection module 600 of this embodiment includes a first resistor R1, a second resistor R2, and a voltage stabilizing unit 601, wherein an anode of the voltage stabilizing unit 601 is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to the signal receiving terminal of the control module 400, one end of the second resistor R2 is connected to the signal receiving terminal of the control module 400, and the other end is connected to the negative power input terminal 200. The combined structure is simple, the stability is good, the data acquisition precision is high, and the switch module 500 can be effectively protected.

In this embodiment, the voltage regulator unit 601 includes a voltage regulator tube D1, an anode of the voltage regulator tube D1 is connected to the first resistor R1, and a cathode of the voltage regulator tube D1 is connected to a negative electrode of the external load 700. The voltage-stabilizing tube is convenient to purchase, has multiple models, can meet the requirements and is low in cost.

As shown in fig. 3, in another embodiment, the voltage stabilizing unit 601 includes a T L431Q 2, a resistor R3, and a resistor R4, an anode of the T L431Q 2 is connected to the first resistor R1, a cathode is connected to a negative electrode of the external load 700, a reference terminal is simultaneously connected to one end of the resistor R3 and one end of the resistor R4, the other end of the resistor R3 is connected to an anode of the T L431Q 2, and the other end of the resistor R4 is connected to a cathode of the T L Q2.

As shown in fig. 4, the output short-circuit protection method of the dimming L ED controller of the present embodiment adopts the dimming L ED controller shown in fig. 1, and includes the following steps:

001. after the dimming L ED controller is connected to a power supply and a load, the controller is powered on to operate, initialize and close the switch module 500, and set a signal receiving end of the control module 400, and when the control module 400 adopts a micro control unit, the signal receiving end needs to be set to be in an ascending and descending interruption state.

002. The control module 400 controls the switch module 500 to be turned on, and the external load 700 normally works, at this time, the output of the control module 400 to the switch module 500 is at a high level, and the signal receiving end of the control module 400 is at a low level;

003. when the external load 700 is short-circuited, the voltage at the signal receiving end of the control module 400 is instantly changed to a high level, and when the voltage output by the control module 400 to the switch module 500 and the signal receiving end are both high levels, the control module 400 turns off the switch module 500 for a time t;

004. the control module 400 turns on the switch module 500 again, and the external load 700 enters step 002 if normal, and enters step 003 if the external load 700 is short-circuited.

In this embodiment, t is greater than or equal to 0.5s and less than or equal to 3s, the time t can be set manually, after a load short circuit is caused by too short time, the switch module 500 is damaged by too frequent switching, and longer time is required for recovering the normal load.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, and any modifications, equivalents or improvements that are within the spirit of the present invention are intended to be covered by the following claims.

Claims

1. A L ED controller adjusts luminance, includes the anodal input end of power (100), power negative pole input end (200), connects power module (300) of the anodal input end of power (100), connects control module (400) of power module (300) and the switch module (500) that is used for driving external load (700) of the signal output part of connection control module (400), characterized in that, adjust luminance L ED controller still including gather short-circuit protection module (600) of the signal of telecommunication of external load (700) negative pole, control module (400) is including connecting the signal receiving terminal of short-circuit protection module (600), control module (400) according to export for the signal of telecommunication of switch module (500) and receive come from the signal control of signal that short-circuit protection module (600) gathered the operating condition of switch module (500).

2. The dimming L ED controller of claim 1, wherein the short-circuit protection module (600) comprises a first resistor R1, a second resistor R2 and a voltage stabilizing unit (601), the positive pole of the voltage stabilizing unit (601) is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to the signal receiving end of the control module (400), one end of the second resistor R2 is connected to the signal receiving end of the control module (400), and the other end is connected to the negative power input end (200).

3. Dimming L ED controller according to claim 1, characterized in that the switching module (500) employs MOS transistor Q1 or a triode.

4. A dimming L ED controller according to claim 3, wherein the MOS transistor Q1 has a gate connected to the signal output terminal of the control module (400), a drain connected to the negative terminal of the load, and a source connected to the negative input terminal (200).

5. The dimming L ED controller of claim 1, wherein the voltage regulator unit (601) includes a voltage regulator tube D1.

6. The dimming L ED controller of claim 5, wherein the anode of the voltage regulator tube D1 is connected to the first resistor R1, and the cathode is connected to the negative terminal of the external load (700).

7. The dimming L ED controller of claim 1, wherein the voltage regulator unit (601) comprises a T L431Q 2, a resistor R3 and a resistor R4, an anode of the T L431Q 2 is connected to the first resistor R1, a cathode is connected to the negative electrode of the external load (700), a reference terminal is simultaneously connected to one end of the resistor R3 and one end of the resistor R4, the other end of the resistor R3 is connected to the anode of the T L431Q 2, and the other end of the resistor R4 is connected to the cathode of the T L431Q 2.

8. A method for protecting the output short circuit of a dimming L ED controller, wherein the dimming L ED controller as claimed in any one of claims 1-7 is adopted, comprising the following steps:

001. after the dimming L ED controller is connected with a power supply and a load, the power-on operation is carried out, and the switch module (500) is initialized and closed;

002. the control module (400) controls the switch module (500) to be started, an external load (700) works normally, at the moment, the output of the control module (400) to the switch module (500) is at a high level, and the signal receiving end of the control module (400) is at a low level;

003. when an external load (700) is in short circuit, the voltage of a signal receiving end of the control module (400) is instantly changed into high level, and when the control module (400) outputs the high level to the switch module (500) and the signal receiving end, the control module (400) closes the switch module (500) for a time t; 004. the control module (400) turns on the switch module (500) again, the external load (700) enters step 002 if normal, and enters step 003 if the external load (700) is short-circuited.

9. The dimming L ED controller output short circuit protection method of claim 8, wherein t is 0.5s ≦ t ≦ 3 s.