CN204836709U

CN204836709U - PWM controls LED lighting device

Info

Publication number: CN204836709U
Application number: CN201520597457.5U
Authority: CN
Inventors: 廖春平; 金友华; 杨宇澄; 吴存宏; 金乃庆; 童怀俊
Original assignee: Whirlpool China Co Ltd
Current assignee: Whirlpool China Co Ltd
Priority date: 2015-08-10
Filing date: 2015-08-10
Publication date: 2015-12-02
Anticipated expiration: 2025-08-10

Abstract

The utility model relates to a PWM controls LED lighting device, include: the door touches switch, photosensitive diode, microprocessor, LED lamp, operational amplifier circuit and PWM control circuit, and photosensitive diode connects operational amplifier's voltage input end, and operational amplifier's output will enlarge AD that voltage signal reached microprocessor and detect the foot, microprocessor's PWM microprocessor 1 output PWM to the base of triode, and the collecting electrode of triode is connected the LED lamp. The utility model discloses a control that the PWM duty cycle gradually changed reduces traditional on -off control to the big current rush of LED lamp, increases the life of LED lamp, whether the too dazzling phenomenon of LED lamp when increasing photosensitive diode and preventing that night from opening the refrigerator detects before the refrigerator someone through installing infrared inductive switch on the refrigerator door, and the maloperation that prevents non - human factor leads to the fact the waste of energy.

Description

A kind of PWM controls LED light device

Technical field

The utility model relates to refrigerator Based Intelligent Control brightness of illumination field, is specifically related to a kind of PWM and controls LED light device.

Background technology

At present, along with the continuous lifting of living standard, the refrigeration plants such as refrigerator have become the necessity in people's daily life, and large refrigerator spreads to huge numbers of families, in the illuminator of cold compartment of refrigerator, usually adopt incandescent lamp or LED to throw light on, but the mode of illumination is all more single.

Lighting device in conventional refrigerator casing is generally made up of mechanical switch and lighting, is namely simply in series by switch and illuminating lamp, and when refrigerator doors is opened, switch closes, circuit turn-on, and illuminating lamp is bright; When refrigerator doors is closed, switch disconnects, and illuminating lamp dead electricity is extinguished, and therefore lacks change, when under midnight or the environment of darkness, open the door of refrigerator, take food or beverage time, can feel that the light of refrigerator inside is special dazzling dazzling, and when refrigerator doors is opened, lighting circuit easily produces instantaneous large-current, thus causes certain impact to lighting, and then reduces the useful life of lighting.

Utility model content

For prior art Problems existing, the utility model provides a kind of PWM and controls LED light device, solves conventional refrigerator illuminating lamp and opens very dazzling night, and the problem that the LED life-span is not grown.

For solving above technical problem, the utility model is achieved by the following technical programs:

A kind of PWM controls LED light device, comprise: door touches switch, photodiode, microprocessor, LED, operational amplification circuit and pwm control circuit, described operational amplification circuit comprises operational amplifier, described pwm control circuit comprises triode, described door touches switch series connection photodiode, the voltage input end of described photodiode concatenation operation amplifier, amplification voltage signal is reached the AD detection pin of microprocessor by the output of operational amplifier, the PWM output pin of described microprocessor exports the base stage of PWM to triode, the collector electrode of triode connects described LED.

Preferred: described photodiode is arranged on outside refrigerator body.

Preferred: described PWM controls LED light device and also comprises infrared sensing switch, and described infrared sensing switch connects described microprocessor.

Preferred: infrared sensing switch is arranged in refrigerator doors relative to the position with human body.

Preferred: described Microprocessor S3C44B0X exports the duty ratio of PWM.

Preferred: described triode model is S8051.

Preferred: described operational amplifier model is LM358.

Beneficial effect:

The utility model provides a kind of PWM and controls LED light device, and the control gradually changed by PWM duty ratio makes LED work, can reduce the heavy current impact of traditional switch control to LED, increase the useful life of LED; Increase the phenomenon that when photodiode prevents from night from opening refrigerator, LED is too dazzling, whether have people before detecting refrigerator by the infrared sensing switch be arranged in refrigerator doors, prevent the misoperation of non-artificial factor from causing the waste of energy.

Accompanying drawing explanation

In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only embodiments more of the present utility model, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is that PWM controls LED light device module diagram;

Fig. 2 is the operational amplification circuit that PWM controls LED light device;

Fig. 3 is the pwm control circuit that PWM controls LED light device.

Embodiment

For making the object of the utility model embodiment, technical scheme and advantage clearly, below the technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.

Embodiment 1:

As Fig. 1, Fig. 2, a kind of PWM shown in Fig. 3 controls LED light device, comprise: door touches switch, photodiode, microprocessor, LED, operational amplification circuit and pwm control circuit, operational amplification circuit comprises operational amplifier, pwm control circuit comprises triode, door tactile switch series connection photodiode, the voltage input end of photodiode concatenation operation amplifier, amplification voltage signal is reached the AD detection pin of microprocessor by the output of operational amplifier, the PWM output pin of microprocessor exports the base stage of PWM to triode, the collector electrode of triode connects described LED, photodiode is arranged on outside refrigerator body, PWM controls LED light device and also comprises infrared sensing switch, infrared sensing switch connects microprocessor, infrared sensing switch is arranged in refrigerator doors relative to the position with human body, Microprocessor S3C44B0X exports the duty ratio of PWM, triode model is S8051, operational amplifier model is LM358.

In Fig. 2, door touches switch sense switch gate signal, extraneous brightness is detected by photodiode, because of the difference of illumination, photodiode resistance value can change, thus make to change through operation amplifier circuit input terminal voltage, through the amplification voltage of operational amplifier output terminal, the AD sending into microprocessor detects pin.

Fig. 3, when ambient light is larger, require that the LED illuminance exported is also relatively higher, but ambient light height to a certain extent, then illumination can be closed.When ambient light is lower, the mode then driven by PWM is slowly progressive highlights LED, and when requiring to export high-high brightness, duty ratio is permanent High level, and when the external world is very bright, opens refrigerator compartment door, does not open illumination, and it exports is constant low level.

It should be noted that, in this article, the such as relational terms of first and second grades and so on is only used for an entity or operation to separate with another entity or operating space, and not necessarily requires or imply the relation that there is any this reality between these entities or operation or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thus make to comprise the process of a series of key element, method, article or equipment and not only comprise those key elements, but also comprise other key elements clearly do not listed, or also comprise by the intrinsic key element of this process, method, article or equipment.When not more restrictions, the key element limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment comprising described key element and also there is other identical element.

Above embodiment only in order to the technical solution of the utility model to be described, is not intended to limit; Although be described in detail the utility model with reference to previous embodiment, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein portion of techniques feature; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the spirit and scope of each embodiment technical scheme of the utility model.

Claims

1. a PWM controls LED light device, it is characterized in that, comprise: door touches switch, photodiode, microprocessor, LED, operational amplification circuit and pwm control circuit, described operational amplification circuit comprises operational amplifier, described pwm control circuit comprises triode, described door touches switch series connection photodiode, the voltage input end of described photodiode concatenation operation amplifier, amplification voltage signal is reached the AD detection pin of microprocessor by the output of operational amplifier, the PWM output pin of described microprocessor exports the base stage of PWM to triode, the collector electrode of triode connects described LED.

2. PWM according to claim 1 controls LED light device, it is characterized in that: described photodiode is arranged on outside refrigerator body.

3. PWM according to claim 1 controls LED light device, it is characterized in that: described PWM controls LED light device and also comprises infrared sensing switch, and described infrared sensing switch connects described microprocessor.

4. PWM according to claim 3 controls LED light device, it is characterized in that: described infrared sensing switch is arranged in refrigerator doors relative to the position with human body.

5. PWM according to claim 1 controls LED light device, it is characterized in that: described Microprocessor S3C44B0X exports the duty ratio of PWM.

6. PWM according to claim 1 controls LED light device, it is characterized in that: described triode model is S8051.

7. PWM according to claim 1 controls LED light device, it is characterized in that: described operational amplifier model is LM358.