CN110996432A

CN110996432A - Dimming method, readable storage medium and LED lamp

Info

Publication number: CN110996432A
Application number: CN201911404513.8A
Authority: CN
Inventors: 付昌进
Original assignee: Shenzhen C&D Electronics Co Ltd
Current assignee: Shenzhen C&D Electronics Co Ltd
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-04-10
Anticipated expiration: 2039-12-31
Also published as: CN110996432B

Abstract

The invention discloses a dimming method, a readable storage medium and an LED lamp, and relates to the field of LED dimming. The dimming method comprises the following steps: calculating dimming discrete data by utilizing a mutual conversion relation between a dimming linear function and another exponential function output by the singlechip; and outputting a PWM signal according to the dimming discrete data to realize dimming. According to the voltage and current characteristics of the LED, the dimming discrete data which can be called by the single chip microcomputer is calculated, so that the PWM duty ratio is controlled to be output in an exponential function mode according to the light characteristics, and the light change seen by human eyes is soft and gentle.

Description

Dimming method, readable storage medium and LED lamp

Technical Field

The invention relates to the field of LED dimming, in particular to a dimming method, a readable storage medium and an LED lamp.

Background

At present, most of LED dimming technologies adopt PWM (pulse-width modulation) signal regulation, and meanwhile, a plurality of single-chip microcomputers on the market support PWM signal generation. The electronic components for adjusting the light output by the PWM signal are mostly a single chip microcomputer, a PWM signal dimming drive IC, an LED lamp bead string and other electronic components such as an inductor, a capacitor, a resistor and the like. In the process of outputting the PWM signals by the single chip microcomputer, the frequency of PWM output can be controlled to control the LED lamp to adapt to eyes of people, meanwhile, the duty ratio of the PWM output is controlled to adjust different brightness levels of the lamp light, the duty ratios of three paths of PWM signals can be controlled to control RGB color change or color temperature mixing of the LED lamp, and the gradual change effect of the lamp light can be controlled by outputting different PWM duty ratios at different time. PWM control techniques are therefore a central part of the light control.

Due to the light emitting characteristics of LED lamps, the LED current is substantially constant or small when the LED dimming voltage is small, whereas when the LED voltage is in a critical range, the LED current varies greatly as long as there is little voltage variation. When writing the PWM dimming software code, the characteristics of the LED lamp are followed, so that the change of the LED lamp light looks soft and comfortable to human eyes. Conventional PWM control of LED lamps does not follow such lamp characteristics well. The traditional LED lamp PWM control method can only linearly adjust the duty ratio change of PWM according to the one-grid-by-one of a single chip microcomputer register, the linear change is not suitable for the characteristics of LED lamp light, the control method causes that the LED lamp has sudden change feeling of the lamp light at the time of pause when the dimming changes, and people look very steep and uncomfortable.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a dimming method which can control the PWM signal to be output in an exponential function according to the light characteristic, so that the light change seen by human eyes is soft and gentle.

The invention also provides a computer readable storage medium.

The invention further provides the LED lamp.

In a first aspect, an embodiment of the present invention provides a dimming method, including:

calculating dimming discrete data by utilizing a mutual conversion relation between a dimming linear function output by the single chip microcomputer and another exponential function, wherein the exponential function is determined according to the voltage and current characteristics of the LED;

and outputting a PWM signal according to the dimming discrete data to realize dimming.

The dimming method provided by the embodiment of the invention at least has the following beneficial effects: the PWM signal can be controlled to be output in an exponential function according to the light characteristics, so that the light change seen by human eyes is soft and gentle.

According to the dimming method of another embodiment of the present invention, the step of obtaining the discrete data by using a mutual conversion relationship between the dimming linear function and another exponential function output by the single chip microcomputer specifically includes:

calculating first discrete data according to a dimming linear function output by the single chip microcomputer;

calculating second discrete data according to the other exponential function;

and calculating the dimming discrete data by using the interconversion relationship of the first discrete data and the second discrete data.

According to the dimming method of the other embodiments of the present invention, the dimming linear function output by the single chip microcomputer is: and y is (x/11059) × 100%, x is the PWM duty cycle, and y is the output power.

According to further embodiments of the dimming method of the present invention, the exponential function is: y is 0.1e^0.0138xX is the PWM duty cycle and y is the output power.

In a second aspect, an embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the dimming method described above.

In a third aspect, an embodiment of the present invention provides an LED lamp, and the dimming method is adopted to adjust the light of the LED lamp.

Drawings

Fig. 1 is a schematic flow chart illustrating a dimming method according to an embodiment of the present invention;

FIG. 2 is a graph of a dimming line function according to the present invention;

FIG. 3 is a voltage current characteristic of an LED according to the present invention;

fig. 4 is a graph of an exponential function of the present invention.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

In the description of the present invention, if an orientation description is referred to, for example, the orientations or positional relationships indicated by "upper", "lower", "front", "rear", "left", "right", etc. are based on the orientations or positional relationships shown in the drawings, only for convenience of describing the present invention and simplifying the description, but not for indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. If a feature is referred to as being "disposed," "secured," "connected," or "mounted" to another feature, it can be directly disposed, secured, or connected to the other feature or indirectly disposed, secured, connected, or mounted to the other feature.

In the description of the embodiments of the present invention, if "a number" is referred to, it means one or more, if "a plurality" is referred to, it means two or more, if "greater than", "less than" or "more than" is referred to, it is understood that the number is not included, and if "greater than", "lower" or "inner" is referred to, it is understood that the number is included. If reference is made to "first" or "second", this should be understood to distinguish between features and not to indicate or imply relative importance or to implicitly indicate the number of indicated features or to implicitly indicate the precedence of the indicated features.

Example one

Referring to fig. 1, a flowchart of the dimming method in the present embodiment is shown. The method comprises the following steps:

s100, calculating dimming discrete data by utilizing a mutual conversion relation between a dimming linear function and another exponential function output by the single chip microcomputer;

and S200, outputting a PWM signal according to the dimming discrete data to realize dimming.

Firstly, the LED light can output the brightness intensity change from 0% to 100% by using the PWM signal output by the singlechip, and a table of PWM pulse width modulation is listed firstly as shown in Table 1. The table is presented as 14-bit binary data, which represents that the PWM pulse width duty ratio can be modulated up to 16384 (14 th power of 2) levels, and only discrete data of the PWM pulse width duty ratio and the output power of 11059 levels are listed in table 1 as the first discrete data. The data formula of the table follows a dimming straight line function y of (x/11059) × 100%, x representing the PWM duty cycle and y representing the output power.

TABLE 1 relationship of PWM duty cycle to output Power

The curve was plotted for y ═ 100% (x/11059), as shown in fig. 2.

Next, as shown in fig. 3, a voltage-current characteristic curve, i.e., a current-voltage characteristic curve, of the LED is shown. It can be seen from fig. 3 that the voltage and current of the LED lamp change in an exponential manner, so that the duty ratio of the PWM signal output by the single chip microcomputer changes in an exponential manner when the lamp light is adjusted by the PWM signal, and the lamp light adjustment is softer and gentler.

Taking an exponential function y similar to the LED light characteristic curve function as 0.1e^0.0138xX is the PWM duty cycle and y is the output power. A graph of this exponential function is shown in fig. 4.

List index function y 0.1e^0.0138xAs shown in table 2, the second discrete data is the discrete data of (2). In Table 2, x is an integer of 0 to 500.

TABLE 2 relationship of PWM duty cycle to output Power

In conjunction with tables 1 and 2, the values of both functions output power y are 0 to 100, so the equation can be established:

(x1/11059)*100％＝0.1e^0.0138x2

x1 is the PWM duty ratio of (x1/11059) × 100% for the dimming linear function y1, and x2 is the exponential function y2 ═ 0.1e^0.0138x2PWM duty cycle of (d).

Since the output power y2 of the exponential function has been listed by table 2, a table of PWM duty ratio x1 versus output power y2 can be found from the above equation and the discrete data y2 in table 2, as shown in table 3. It should be noted here that, since the PWM duty ratio x1 output by the single chip microcomputer cannot be a decimal, the repeated x1 and the corresponding y2 values are discarded by rounding, and only 1 is left.

TABLE 3 relationship of PWM duty cycle to output Power

The data in table 3 is dimming discrete data. The dimming discrete data are stored in the single chip microcomputer, the single chip microcomputer can call the discrete data to perform dimming, and due to the data conversion, dimming is changed according to an exponential function, a voltage and current characteristic curve of the LED is well followed, so that light change seen by human eyes is soft and smooth.

It is understood that the exponential function selected in this embodiment may also be other exponential functions, and only a curve function similar to the voltage-current characteristic of the LED is required. Through the data conversion, the control process of the light gradual change can be completed.

Example two

The present embodiments provide a computer-readable storage medium storing computer-executable instructions for causing a computer to perform a dimming method as described in embodiment one.

EXAMPLE III

The embodiment provides an LED lamp, and the dimming method as described in the first embodiment is adopted to adjust the light of the LED lamp.

For the dimming process, please refer to the description in the first embodiment, which is not repeated herein.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

Claims

1. A method of dimming, the method comprising the steps of:

2. A dimming method according to claim 1, wherein the step of obtaining discrete data by using a mutual conversion relationship between a dimming linear function and another exponential function output by the single chip microcomputer specifically comprises:

calculating second discrete data according to the other exponential function;

3. A dimming method according to claim 2, wherein the dimming linear function output by the single chip microcomputer is: and y is (x/11059) × 100%, x is the PWM duty cycle, and y is the output power.

4. A dimming method as claimed in claim 3, wherein the exponential function is: y is 0.1e^0.0138xX is the PWM duty cycle and y is the output power.

5. A computer-readable storage medium storing computer-executable instructions for causing a computer to perform the dimming method according to any one of claims 1 to 4.

6. An LED lamp, characterized in that the dimming method of any one of claims 1 to 4 is adopted to adjust the light of the LED lamp.