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The drive control LED solution base on power management chip

Design solution:
LED is an excellent display, it has advantage such as: long service life, save energy , high brightness, various light colors, fast response , drive low power. Can be service energy through adjust LED luminous intensity. according to the RGB tricolor light mixing principle of regulating a variety of colors, and then control to achieve a variety of display results by MCU intelligent. Now a lot of applications in the field of city lighting, architectural landscape lighting, stage lighting design. The design solution by NXP semiconductors (NXP) power management chip, micro controller, I2C devices, LED driver, to provide a full design solution for the design of LED lighting system.
Mainly application:
1,point source:
base on LED color screen display principle,the pixel amplification, reducing the overall cost, echo module is a color pixel.application environment: bar, KTV, stage, exhibition hall, as the music melody display, background wall decoration,wall advertising etc.
2,LED rainbow tube:
echo lamp is composed of a plurality of color pixels(RGB) , each monochromatic pixel can produce 256 gray level changes. Application environment: decorative lighting overpass guardrail, river, building walls and other different places.  system hardware design:LED color control system mainly include: drive module, control module , LED power。
1,drive module design:
How to achieve to show difference colors, which rely on intermittent inertia principle of human vision, using the R, G, B duty ratio of RGB LED color mixing. LED color display of this design mainly relies on NXP’s I2C interface LED blinks/mixed light driver IC PCA9633 (PCA9633-4-bit PWM output, PCA9634-8-bit PWM output, PCA9635-16-bit PWM outputs) output 256 grayscale colors for color display.LED controllers just need to transfer the gray value of the RGB color of the module can be implemented a color display.
PCA9633 is I2C bus control programmable PWM outputs of the 4 bit LED drive units,main application: LEDRGB/RGBA(Red/Green/Blue/Amber)mixed light, main performance indicators are as follows:
1、 the 4-channel LED driver, each drive can be programmed to 4 kind of States, namely: on, off, blinking programmable PWM control output, programmable per channel grayscale level, while supporting the overall dimming PWM mixed light output.
2、 dimmer control, PWM output frequency 97kHz, each channel with 256 levels of gray.
3、Flash control, PWM programmable frequency range as 24Hz~10.73s, duty cycle range of programmable as 0%~99.6%.
4、 available through the 190Hz PWM output to adjust 256 grade four PWM output overall brightness.
5、 4bit output programmable settings as push-pull output (5V, sink current 25mA, pull the current as 10mA).
6、 set PIN 7 hardware address, with a maximum I2C bus can be connected with 126 tablets.
7、each PCA9633 has four programmable software address: a full response to the address and three sub address.
8、 built-in 25MHz oscillator and a power on reset circuit, can realize the software reset by I2C bus.
9、 SDA/SCL built-in noise filter, supports 1MHz I2C fast-mode.
10、supports hot insertion and low standby current, voltage range:
2.3~5.5V.

3. power supply
Power supply according to the specific quantity of LED, and connections way to determine the specific parameters。 below adopt the NXP STARplug series chip LED power solution, the design is simple, small size, wide range voltage input, low-cost, advantages of low loss, was widely used in LED field.

Application of LED downlight lamp

Refer to the downlight lamp,in order achieve greater development in the field of indoor lighting。We should consider the following principles and directions:
1,To put the use the LED dwonlight faster starting,convenient to adjust lighting advantages,priority of application : requirement for sound,light in self-control and require  adjust light or frequently switch lights and other places。
2,Should be select the spot, expanded step by step, escalate,sum up experience,avoid to not the analysis conditions,large area promotion。base on downlight advantage as entry to find suitably work spot。
3,utilize the advantage of LED color lighting,used in the indoor decoration for higher requirements,or as the ceiling decoration, background lighting etc…
4,LED downligh lamp shall accordance with the 《architectural lighting design standards》requirement, including illumination, uniformity, glare, color rendering index requirements and affordable color temperature to achieve good visual conditions and limits specified LPD.
5,Using LED downlight lamp directional emission light characteristics, applications that require directional lighting parts, such as supermarkets, jewelry counters, and so on.
6,We consider that LED downlight should highlight the energy-saving effect: in currently ,to replace the inefficient incandescent lamp is first goal。The second goal is replace the halogen; third is to try to gradually replace the compact fluorescent lamps. Special Note: Not all of LED is energy-saving lamp,should be reaching the same level of illumination, to compare the quality of lighting conditions.
With the development of the LED industry is mature, The LED downlight lamp industry and market will be to gradually opening , LED Lighting projects  has chance acceleration of replace the traditional incandescent lamp, energy saving lamp lighting products.

LED bulb power supply

  1. The LED bulb requirement
    Because of the need to replace the incandescent,so must have at least the following requirements:
    The wattage is reference standard without lumens for the LED incandescent。the led luminous is Continuous to progress。The power of led does not representation of LED luminous 。the incandescent most commonly to using type has 15 watts, 30 watts, 45 watts, 60 watts, 75 WATTS and 100 watts etc。if only to discuss the led luminous,then can be calculated with the luminous efficiency of LED。The LED light efficiency of incandescent as 7.5-12lm/W。the high watts give birth to greater the LED light efficiency。correspondence of parameters between the led watts and led light efficiency, can be list as follows。

Wattage W  15   30    45    60   75   100
Incandescent Efficiency 7.5   8   8.5   9.5   10.5   12
LM         112.5 240   382.5 570   787.5 1200
LED1         Wattage W   1.56  3.3 5.3 7.9   10.9   16.6
LED2         Wattage W   1.2  2.6  4.1   6.1   8.4   12.8

led replacement lights

NOTE:Filament lamp= electric incandescent lamp
led replacement lights

If using led replacement lights, can also draw the correspondence wattage。But the LED efficiency is continuous progress, so it is difficult to give a exact figures。Assume now commonly used LED1, the light effect is 100lm/W, if the highest light effect of the LED2, the light effect is 130lm/W (warm white light effect will be less than this value). We can draw on the two kinds of light effect LED。But because LED needs constant current source, and the constant current source has a certain efficiency, assumed to be 85%, and because LED cannot use the transparent bubble shell, but only the use of creamy white foam shell. Its light transmittance of about 85%。Multiplied by two equals 0.72。After considering the factors above. We can draw the correspondence of incandescent lamps wattage。 As shown in the table, the power LED2 can save 10 times in about the same brightness。 Have a bit need special explanation. Is from the current LED bulb lamp light efficiency and heat dissipation, it is impossible to do more than 10 watt, in other words,there is only 60-75W can replace incandescent lamp LED bulb. Of course, the PAR lamp is another matter (which will be discussed below) 。
The following basic index of LED bulb power supply:
1,Basic types of power: Mainly consists of isolated and non isolated, refers to the load part is isolated from the Firewire(AC part)。in general,no isolated not has transformer,so the cost is low, but the requirements of high pressure aluminum plate,otherwise there may be charged on the radiator。So it is not easy through the safety inspection。Isolation mode is more safe,more easily through the safety inspection, but the cost is high。
2,Power supply output power: The size must be same between LED bulb and incandescent lamp。So limited the size of radiator,at present, no more the 9W。
3, Power efficiency: In general isolated mode in about 80-85%, non isolated in about 90%。
4,Power factor(PF): about 0.5-0.6 without PF correction,Has PF correction at around 0.9-0.99
5 Size: because the bulb to the power of the space is very small, so the volume restrictions are very strict。

DALI vs DMX512(DALI and DMX512 application difference)

According to Various of bus protocol system,in addition to DMX512 and DALI deeply into the internal of lighting products。Other protocol just only to the wall of the connector and socket,not In deeply to internal of lighting products。In other words hadn’t unified standard according to the characteristics of various lighting and lighting terminal products, it is impossibility of open the function of lighting products。So,on one hand,they are only general simply on-off control and phase chopper。So ,has the very big limitation in the intelligent application of ordinary to office and family。and limited them to enter the general lighting market。On the other hand,because there hadn’t unified standard according to the characteristics of various lighting and lighting terminal products。And not have to in deeply to internal of lighting products。For various of lights products input supply to general simply adjustments to achieve the dimming purposes。Is easy to appear the lights flashing。Damaged the ballast controller or tubes,etc., and even produce a security problems.Although the DMX512 into the internal of lights product。but the system is mainly for large stage lighting lamp design, many functions of the main consideration is the motor mechanical control, and no more consideration for the electric control by program cord。It’s not suitable for the ordinary office building lighting and household lighting in intelligent application。But some lights products with DALI digital addressable lighting interface。So as international unification standard into the intelligent ordinary office light and ordinary family light。The DALI digital addressable lighting interface is most promising, high quality and intelligent lighting control system。 The rapid development of DALI digital addressable lighting interface technology and DMX512 lighting technology application to update play a tremendous role in promoting。

Questions of DMX512.

Below will answer the questions of DMX512.

I has question of DMX512 for you,this is roughly thought as follows:
I will be do a system that is simply control the lights products with MCU to process a signal of DMX512。so that there are several lamps can be terminal. A very simple system, a controller, a few lamp terminal。The controller sends a 512 signal to control each lamp state。Now 512 protocol is based on RS485, is half duplex, how to identify the data packets belong to the lamp terminal。

Answer:
Some things do not understand ah, please told me a simple control structure, can realize the dimming function that will do, thank you!! In simply words for you,The 512 protocol data packets does not to send address signal ah, how to let the equipment identification? It is a field(data packets) with a corresponding equipment(your device channel N corresponding data packets N )

Flexible LED lamp belt assembly skills

Flexible LED lamp(LED strip) belt adopted a flexible circuit board
Flexible LED lamp belt is used in flexible circuit boards, which is we usually refer to the FPC. FPC itself as soft。Thin (generally having a thickness of 0.15 ~ 0.2mm), so the great difficulty when assembling.

1, difficulty of the circuit board print
Because FPC is too soft, too thin, so positioning became a problem. Previously, many people are using double-sided tape to fix, but the shortcomings that the printing job is finished after the double – sided tape is difficult to take down, affecting production efficiency and quality. Later someone with a jig, using in the fixture to achieve a fixed position, so although using fixture to progress than some, but because of the use of edge location is not very accurate (FPC is too soft, it will moves), will also affect the quality. Later on the use of self-stick silicone to make the jig, efficiency and quality are guaranteed.

2, the patch of difficulty
Because the LED lamp belt are relatively long ,most is 50CM long, the shortest has 30CM, SMT machine stroke are not enough,if the pasted half back again with the other half of the words, it will affect the efficiency, and because mobile positioning, so stick Precision sheet is also not guaranteed.

3, the difficulty of reflux
Because FPC lights with long, with thin, and reflux temperature lead-free solder paste is also very high, which will result in overheating and warping FPC, the impact of LED placement position thus affecting the quality of products, and if the reflux temperature down and reach the melting point of solder affect welding results.
The general practice is to use a jig, there have place of fixture hole in the LED below, so that the reflux temperature of the heating for the needs of the welding place, and its places due to fixture barrier and lower the temperature, no warping effects of welding accuracy.

4, the difficulty of repair
Because the FPC is thinner,so the perseverance of high temperature relatively short time. LED lamp belt if adverse goods need to rework the words, then you need to pay attention to the temperature of the soldering iron (not more than 300 degrees) and welding time (not more than 5 seconds), otherwise it will cause FPC blistering, soak the entire product is scrapped. So when maintenance is critical to control these two aspects, maintenance personnel Skill to master is also critical. These are some tips and considerations LED lights with the chip assembly process。

Stage of lights

1, overview
The function positioning stage is: to held various meetings, and can also be To give a performance or shows.
stage lightsstage lights1

2, the scope of design:
According to architectural design plan of center stage light system designed of center stage divided into as follows:
1)Stage light

2)The top stage light

3)Electric hanger stage lighting, stage along the screen, lintel curtain, vertical curtain, two curtain, screen frame, empty spare rod up and down for maintenance for the scene, need be designed.

3)design principle:
Light system project, in whole process of the implementation scheme and design schem. Light configuration, pay attention to actual effect, to achieve the best price performance ratio。which is one of the design principles. Combining the function orientation, the input of funds, to ensure the effect and leave room for expansion, is the design principle of the two.
4, Description of stage lighting plan
1) stage light:
The stage surface light by 6 PCS(2*36w) stage soft light component. Surface light main function is light to the front of the stage, is the basic lighting figures and table scenery. According to the need for all kinds of stage. with light volume through simple control timely(by LED controllers), the lamp is 2 PCS 36W/U lamp tube.average illumination lamp for 3600K, soft light, color temperature lamp eye open quasi, almost no harsh feeling, is the essential source of photography. Is the first choice of lamps and stage and studio.
2) The top light of stage,
Over the traditional stage is almost always a curtain lamp and PAR to compose. Even the lamps in the large stage venue with a inconceivability。such lamps in use not only the low illumination; and more of a risk to the safety!If used for a long time, but also make the stage suspension brought into light heat, A new three color cold light lamp will be completely resolved in the past can not solve the problem.
Three color cold light lamphas 5 major characteristics:

1, long service life: 10000 hours service life of the lamp, isten times than thermal light bulb, if use 10 hours per day calculated, does not need to replacement lamp for three years.

2, low temperature: tube surface temperature is low, the irradiated object almost no warming phenomenon, is the real meaning of “cold” light, so completely solves the stage due to high temperature phenomenon.

3, small power: the average power of each lamp in between 72~330W, power-saving 70% above than the heat light source lamp, a small stage or power consumption does not exceed 2KW.

4, color temperature quasi: lamp color temperature to 3200K, the upper and lower error only less than 1.5%, can fully meet the requirements of light source technology . The color index is 95, with good color reduction. Completely solved due to temperature is not stable and cause the announcer facial partial color phenomena caused by the past with the heat lamp light source.

5, soft light: light uniform, soft, stager thinks generally, eyes feel comfortable, no glare phenomenon.

The layout design of the lamp according to the construction plan are provided, namely placed 8 pcs three primary color lamps on the stage at the top

Music to control light beat of night show with the MCU

In automatic control system, MCU to realized a music control of automatic and intelligent。In automation technology control system, the use of MCU realization of the music lighting control automation, intelligent, and without the need of human intervention then automatically adjust a better feeling with light musical transformation, to achieve the integration of sound and light.
This system is only a simple design idea, it’s just a model, hasn’t directly put into use.But the success of this system shows that the design can be realized, and as long as the appropriate hardware and software modifications may be applied to many fields. For example, you can design LED display, LED lighting decoration series products etc..LED display series can be: LED variable message signs, LED variable speed limit signs, LED lane controller, traffic lights, countdown display for licensing fees, card, canopy lights, and various series of indoor and outdoor LED display. Making LED decorative lighting series are: used in bars, dance halls, nightclubs, clubs, leisure centers and other places of entertainment LED color curtain, LED color, LED color ground smallpox, the external walls of buildings (or profile) night lighting and decorative wall display etc.. Here’s to the bar display screen as an example to analyze how to improve the system will be applied to reality. Prospects for the development of a system application and development 1.1 system。First, the display part with full-color LED instead of uncolored LED, with a MCU to control full-color LED display screen will become DISCO upscale bars, night show, the most advanced lighting products market. Due to the application of the MCU technology and digital signal processing technology, , so different from the ordinary decorative lighting, is also different from traditional laser stage lights. It appears on the traditional decorative lighting night show presented a great challenge, but also make decorative lighting night show entered a completely new era.
Music to control light beat of  night show
By appropriate control, it can produce a variety of dynamic screen effect according to the melody, rhythm and shade and color changes and, express a kind of secret dream away, dazzling mysterious, gorgeous colorful background lighting. DISCO thus caters to upscale bars, night show  arena has requirements for lighting background, will become the latest highlights of the current night show  decoration.

MCU control of full color LED display screen has the advantages:

1, a great variety of colors, 256 gray levels, more than 1670 million colors let you choice;

2, To make realistic— realized a music control, can be controlled through a MCU according to DJ playing disc and live music control LED display and wall led changes, to realized the music and light seamless connection, let the light and sound volume capacity in one;

3, well-designed control software, a friendly user interface, and with multi-window multi-page display, shortcut keys, make DJ easy deployment of sound and light show wonderful, fantastic changes; development of such applications to adapt to the times , keep synchronous development with the advanced technology in future, there will be more development prospect.

Explosion proof lamp of knowledge summary

1. Explosion-proof lamp shall be provided a permanent and eye-catching logo “Ex” with embossed or concave pattern。 A prominent place in the shall to be provided nameplate. Warning signs should be clearly visible, set in propriety place. Such as “off the power after opening the lid” warning signs shall be install at openings nearby.
2 because of explosive dangerous location is often associated with the presence of corrosive gases, so the symbol of explosion-proof lamp shell shall be with thickness not less than 1mm (small lamps and lanterns thickness not less than 0.5mm) bronze, brass, stainless steel or corrosion resistance than other material made。 Should also be reliable fixed, not easy to fade or fall off.
3,The methods of test marker durability is: after using water-soaked cloth graze 15s to be dry, and then using gasoline soaked cloth graze 15s, visual inspection, signs should be clear, not falling.
4. Content of nameplate signs should include:
A) explosive proof mark.
B) basic signs: including product name, model number, manufacturer name, registered trademark, manufactured date.
C) performance safety signs include: rated voltage, current, nominal frequency, light source power , quantity, allowable ambient temperature (the range is -20 ~ +40 ℃ not standard), the specific application of environmental labels (such as to apply only one kind of explosive gas mixture of products, shall be marked with the name and molecular formula of combustible gas), luminaire classification symbol (such as “digital) and so on.
D) explosion-proof certificate number, that the product has the explosion-proof test stations officially tested by. Some products are explosion-proof certificate No. with the “X” symbol, which shows that this kind of product can only be used in some special security conditions of use, should be clearly marked to indicate the conditions prescribed in the lamp shell or product specification. Special security conditions there are many types, users see the proof certificate number after the “x” symbol, they should pay attention to understand the kinds of products to find exactly what special security conditions, in order to properly operate the installation process to avoid danger.
D) annotated. In addition to the mark, in order to ensure the correct installation details required, use and maintenance of detail required, shall be in the lighting, or the built-in ballast and lighting products provided with the manufacturer’s instructions are given. For example:
A allowable working position of explosion-proof lamp, explosion-proof lamps are only allowed to use some installed in a position or a certain angle range, this is because the position the change, the heat distribution explosion-proof lamps surface and the maximum surface temperature will change, the reason for the explosion-proof lamp position limits, the main the reason is that in order to control the maximum surface temperature, not to let the temperature over explosion-proof lamp itself marks, brings dangerous temperature. Therefore, the explosion-proof lamp installation position limit must be clear.

LED explosion –proof lamp knowledge

An safe explosion proof LED lights, belong to the electric equipment of specially industry。Mainly to resolve the lighting problem。Which include a lamp shell, lamp shade , inner light , battery ,and set in switch lamp shell surface。Which is feature:the luminous is high power LED module。the input driving voltage is widely between the luminous body and battery ;widely voltage includes: constant current chip, battery and constant current mode together to comprises a power module。LED module is connected to the constant current chip, power supply module and the LED module encapsulation together; between the lampshade and lamp for ultrasonic welding。a switch connected between the chip and the battery, and a constant current waterproof switch,It uses LED low heat characteristics to achieve proof intrinsically safe level, and long battery services time of LED light source; LED con be maintain a constant brightness in full charge and discharge stage; cooling device is arranged in the lamp shell, which can be effective heat dissipation, and to ensure the stability, suitable for coal mine, petroleum, railway, flood control etc. a variety of lighting industry.