24/11/2011

Lithium-ion battery and battery charger reference design

Presentation


The portable electronic work with the battery. With the rapid development of mobile products, has increased the amount of the battery, and a lot of new batteries. In addition, we are more familiar with the alkaline batteries, rechargeable nickel-cadmium, nickel metal hydride, not in recent years of large lithium-ion. This will introduce lithium-ion, including knowledge of the properties, the key parameters, applications and provide the last line of lithium-ion Dell Inspiron 1200 Battery design reference.


Development and application of lithium batteries


Lithium batteries are currently the most common battery is new, in accordance with the requirements of various electronic products in a flat, rectangular, are cylindrical, rectangular converted, and a button that you can insert a low-power applications can use also multistage series-parallel combination to be a higher voltage and capacity of HP elitebook 2530p Battery power tools and laptop computers. Lithium-ion can be a gel electrolyte, the polymer (Li-Ion / Li-polymer), or a mixture of polymer gels. Why not at room temperature, the actual supply lithium-ion polymer is, most lithium ion / polymer battery is actually a combination of gel-polymer hybrid battery.


Lithium batteries are different from chemical batteries, loading and unloading of his work through the process of integrating the positive and negative electrodes of lithium-ion battery and scope, while recharging the battery, the cathode generation Lithium-ion generation lithium ion moves to the cathode through the electrolyte. Since the carbon anode was layered structure, has many pores, reaching negative electrode of lithium-ion layer of porous carbon, integrated lithium-ion, more resilience built. Similarly, if the battery Dell Inspiron Mini 1012 Batteryis low, the carbon layer embedded in the cathode of lithium-ion extrusion, and again at the cathode. Back to the cathode of the discharge capacity lithium-ion is higher. In general, we refer to the battery capacity refers to the drainage capacity. The charge-discharge process, lithium ions in the cathode to the anode to the cathode, the cycle of movement. Since the lithium-ion batteryDell Vostro 1310 Battery lithium-ion state rather than lithium metal, with a low risk, high security use.


Characteristics of the battery


Performance parameters of the battery are the strength, skill, energy and power. Electromotive force equal to the unit positive charge from the anode to the cathode of the battery, the battery is not static (chemical forces) at work. Electromotive force depends on the chemical nature of electrode materials, and size of the battery. This is the total output of the battery, the battery capacity, usually in ampere-hours.


The response of the cell containing the substance per kg of product with the current theoretical specific energy of the battery. Refers to the energy per unit weight or unit volume specific energy stored Wh / kg or Wh / L to represent. WH is a unit of energy, WW, h is the hour in kg (weight), L is the liter (volume). The real power of the Dell Vostro 1500 Battery, the theoretical specific energy than small ones. Because the battery is not all reagents in the reaction after the battery while the battery internal resistance causes a voltage drop. On the other hand, the current through the battery reduces the cross-section through the resistance. Lithium-ion is the highlight of today's high-tech lithium-ion energy can reach over 80 kg ~ 120 Wh /, while the traditional lead-acid battery is only 30 ~ 40 Wh / kg, and lithium - ion battery can store energy in a small format, can only bring out the light for mobile computing devices and applications demanding the life of the electric vehicle.


The following list contains some properties of lithium-ion battery: High capacity Li-Ion is the same weight capacity of nickel-cadmium or nickel metal hydride, half the volume is 20-30% of the nickel-cadmium, nickel-hydrogen from 35 to 50%.


● high-voltage lithium-ion battery voltage of 3.7 V (nominal), the equivalent of three sets of nickel-cadmium or nickel metal hydride batteries.


● High stability: Due to non-lithium, low-risk, and therefore beyond the reach of the operators of aircraft to the limit to implement the plan.


● Long life lithium-ion batteries battery dell vostro 1500 are fully charged, the voltage drop of about 4.2 volts, the discharge voltage is stored, but not less than about 2.5 volts, the voltage of the voltage plant, about 3 to 6 to 3.7 volts. The key number for the life of the burden of a life long lithium-ion battery of approximately 500 times (from 2.5 volts to 4.2 volts charged only counted once), and the memory effect of lithium -ion ​​battery is not present.


● Quick charge a nominal voltage of 4.2 V DC voltage / constant current charger can be lithium-ion-1 to 2.5 hours at full load. Note, if the charging voltage of 4.3 volts or more, there is the danger of an explosion. The battery voltage drops below 2.0 volts, the loss of lithium-ion battery, can not use or being charged.


Charging the battery


Can "to solve the load IC," say the above, although requiring lithium batteries Vostro 2510 Battery with high power and benefits of long life, but the loading and unloading aspects of attention to all the lithium- ion recharge and discharge set the border to ensure that the battery voltage through the security of explosion if the battery voltage to avoid causing reduced production below 2.5 V on the life the battery. In addition a number of standards, sees most of the lithium battery of different sizes for the practical application of basic properties are not the same, so the current project is supported by some manufacturers. Depending on the size of the loading mode charging current so-called fast or slow, you can download the current mode is generally harmful to life. Even if the battery contained in a charging circuit for the integrated management, but only to avoid the explosion of the battery or the minimum measures to protect against burns, rather than normal use, to fully realize the Inspiron 2650 Battery and the efficiency ", the rest of this sophisticated design and Chargers lower limits as well.


In addition to the excessive discharge, lithium batteries are not suitable for high pressure discharge lamps, high relief reduces the discharge time (internal temperature will produce a greater loss of energy). Therefore, the maximum battery manufacturer's specific products currently in use less than the maximum discharge current. Lithium-ion for the needs of high quality require sophisticated Inspiron 1525 Battery charging circuit for the security, in particular, to stop the charge voltage accuracy of 1% of the nominal value (eg 4.2 V lithium ion tolerance of ± 0.042V) below circuit voltage lithium-ion battery can cause permanent damage, severe cases leading to the explosion of the battery, lithium-ion battery as specified by the manufacturer of the battery . Although some of the rated load current of the battery 2C (C is the battery capacity 1000mAh, 1C charge when the charge current is 1A is checked), but the load reduces the battery life at high currents, so that the density of ~ 0.25c 1C general use. To produce by the head of the electrochemical reaction to heat, the energy loss to other lithium batteries are not all consistent with the load in constant voltage mode here, so real-time charge of approximately 2 , 5 hours, lithium ion temperature between 0 ~ 60 . Excessive load current is generated when the temperature is too high, not only cause damage to the battery and an explosion. Therefore, the current capacity, detecting the temperature of the Inspiron 1545 Battery, and if the temperature along a levy on the task of adopting security. In addition to the load circuit, the current limiting resistor to ensure that the load current is not the limit of the current intersection.


Lithium-ion battery is often three-step method of collection, pre-load (pre-charge mode), a (fast charge mode) at constant current, constant voltage (constant voltage mode) are used. Discontinuation of lithium-ion battery discharge voltage of 2.5. May well designed battery chargers to determine the battery power that pre-treatment before the formal charges to spare. Supported by the demonstration of the battery if the battery voltage greater than 3V as a function of normal load and the battery Inspiron 1720 Battery voltage drops below 3V, the scene of a low current (about 10% of the load current, in constant current mode) is called the burden of pre-charge mode, so the depth of discharge in a state of dissolution of the passive film restored. In addition to causing excessive discharge when the battery can cause, and a whole bunch "of copper anode in a short-circuit currents in excess of strength in this time, the overheating of the Inspiron 1521 Battery, but pre-loaded at this stage to avoid. 3V or other expenses, while the normal mode, the load voltage constant.


If the battery voltage greater than 3V, depending on the load characteristics of the normal load of Figure 1 (a 4.2 V lithium-ion battery, for example). He began to load in constant current mode, the battery voltage to rise to a faster increase of the slope, with the increase of the battery, the Vostro 1500 Battery gradually decreases the slope of the voltage rise to about 4 , 2 V, constant current is over. Change a constant voltage charger is 4.2 V, constant voltage phase of charging voltage is almost constant, but the decrease of the load current. If the load current to a value to activate the timer, the timer is a period after the loading process succeeds.


Constant charging voltage accuracy of the Inspiron 6000 Battery output voltage with a maximum capacity of the battery and autonomy are important. If the battery voltage falls below 4.2V, the charger can cause a breakdown, if not, your life, but it makes the battery capacity is reduced. For example, as the state of charge is less than 1% of the total voltage of the battery capacity is reduced to 8%. On the other hand, the battery voltage is too high, reduce congestion and battery life, or even that the user is in danger. To ensure the safety of lithium-ion battery allows you to charge the battery when the ambient temperature between 0 ~ 45 . Charged at a lower temperature, lithium, the impedance of the battery and the deterioration of the battery. In a high temperature environment for charging, the electrolyte increases the reaction with lithium and accelerated deterioration.


Generally, we recommend that long ago, if not used, put the battery from 70 to 80% for storage should be kept. It is a long period of natural drainage of the battery voltage to prevent the sub-ion 2.0 volts, which can not be a failure of the lithium ions are used. Often short of lithium batteries with loading and unloading is often used, life expectancy reduced by about half.


Lithium-ion battery is designed to taste


To answer these products at low power chargers for portable applications more accurate and safer, many chip manufacturers to develop low-cost linear charger. 2 is loaded by Kerry Technology LD6275 example circuit design, some parts of the linear circuit of the load independently, the maximum current of 1.5 A is.


LD6275 is integrated linear Li-Ion battery charger integrated circuits, route of administration is active, the load currents in the case of loading / unloading, the adjustment in the Inspiron 6400 Battery life in real-time monitoring input and ongoing management (eg, power output USB port), in accordance with USB - If the call default limit current and soft start function. In addition, a high-temperature measurement IC when the temperature exceeds the set value IC. Automatically reduces the charging current to the chip damage.


Avoid LD6275 AC adapter / USB 5V DC step-down constant current lithium-ion battery, AC adapter for protection against overcurrent due to overload, you can set the maximum current strength RCISET external load. USB also supports the loading, and are determined on the basis of external pins EN1 and EN2, see Table 1 for each mode. The USB 500mA mode 100mA in USB mode, you can protect the USB port on the PC side, to prevent overloading.


MAh under the assumption of a single supply voltage of 5.5 V Li-Ion 1200, 0.7 under the conditions of Dell Latitude D820 Battery voltage and 3V raging current, an estimate of the maximum operating temperature IC This 1.762W max power is the thermal resistance at 60 / W, 3 x 3 mm QFN Temperature 127 temperature, even when the ambient temperature of 0 , 125 exceed silicon chip, the maximum temperature. When the load current of 0.6 A (0.5 C), the chip temperature of 90 degrees, and at room temperature of 35 degrees is much better to operate together now.


Can learn from him, faster than the carrying value of the operation voltage constant current and constant, it is important for a linear charger. The fundamental problem is a linear charger when the temperature of the chip is higher, so the design must compromise between the load current and the heat sink. But often, the application of the linear charger for portable products is slightly higher than the use of low thermal conductivity of the plastic should not believe no heat sink metal design of the final product and reduce the load current increases the load at a lower temperature of operation. Users of portable products in the hope that in 1 or 2 hours after completion of the loading process, so that a linear charger is usually best suited for applications such as low capacity 1500mAh lithium-ion battery. Apply to the high XPS M1730 Battery input / output voltage difference and applications of high performance battery, you should consider using the charger synchronous switching regulator.


Figure 6 shows the battery charger lithium ion, standard load, the load of the first integrated circuit short-circuit output and the type of protection against overloads detects if everything is normal, the system detects that the battery 3V 3V or more of the first fast charge mode directly to the ICU, when the Studio XPS 16 Battery drops below 3V to enter into an agreement for the pre-load and 10% of fast charge, the battery alarm to avoid damage the battery. Cut saw in the pre-load and the battery voltage at any time in the 3V immediately after the fast charge mode.


n, the fast charge mode, the battery voltage to a growth rate of 4.2 V, then reduce to a constant charging voltage of 4.2 V, the internal resistance of the battery current to Bunsen, when the load current as shown in Figure Stadium the first CV. Over time, the load current decreases exponentially when the current rate ICHG 10%, or down by the shipper at the same time as loading is completed.


However, if the BatteryDell Inspiron 1300 is discharged, can not store the battery in positions of power, the current does not increase depression, full of energy as heat, high temperature protection, and more time in Apart from several trusts, CI had internal timer of death, or when the battery voltage at the office time to adjust, then turn the charger to a security feature of multi-user access.


The user can load when the load is not without the power of what was to complete a battery. To avoid the risk of IC must be submitted in 7, 8 batteries detection methods. IC, a short pulse (2 ms pulse is generated every 370m) to take the battery if the battery is present, then the battery voltage must be detected above a predetermined threshold and if the battery will be responsible for IC detects a low voltage battery and unplug the Battery For Dell Latitude E6510power for the safety of our users to be determined.


Lithium-ion batteries for its unique performance advantages in portable devices such as laptops, cameras, mobile communication is widely used. The new generation of lithium-polymer battery that can be done in the form of fines, and a region of arbitrary shape, greater flexibility in the design of the battery. Meanwhile,  lithium-ion polymer Dell Inspiron 9300 Battery increases energy than current lithium batteries usually about 20% capacity, and other aspects of performance lithium-ion environment can be improved. It is expected that the future of battery Lithium-ion faster, more robust protection for future development trends.


 

13/10/2011

what it bring to us for the new releases of iPhone iPad and iPod touch

These are HP HSTNN-IB72 applications that made the success of the iPhone. In this sense, could not deny Apple's newest jewel of a measure for the AppStore. In fact, more than 2,000 applications are already available, already prepared to complete pre-installed on the iPad. Unfortunately, there are currently few applications actually designed for the iPad. The fault of the youth of the product and the few copies that are for developers who are able to utilize the capabilities of the device are rarely distributed. Therefore, the AppStore is full most of the applications originally designed for the iPhone, around the tablet are designed to adapt. But this Compaq Presario CQ40 battery situation should change in coming months, with the gradual spread of the iPad.

The first applications

The applications that we have not tested all had failed, but a lot of mistakes, sometimes forcing us to reboot, hoping to enjoy. In this case, the solutions in the coming days must be found, as the developer has a device to have her involved productions.Enfin monitor, remember that even with iPad iPhone Compaq Presario CQ50 battery applications, but in their original resolution or 640 x 480 The tablet can be "exclusively" to double the ad, but the result is too grainy for inviting us. Future owners of iPhone, iPhone applications use in extreme emergency.

The iPad is a digital book?

Currently there are two applications that perform the iPad eBooks: iBook and Kindle. In terms of the offer, the application of the Amazon has a margin of a clear lead, with more than 370 000 references (in English) from 60 000 to native solution from Apple. Have the ability, all I purchased eBooks on the iPhone, download first: Another advantage of the Kindle. These are just the benefits of Amazon, like Apple in terms of features is a lesson to his HP HSTNN-UB72 battery opponent.

First, the iBook is a dictionary that the active control of a single finger. E 'can also be read directly markings or notes in the text. Finally, background iBook (5 choices) and the brightness of the screen. At the end of the HP Pavilion DV9600 battery confrontation between these two references for digital books, I must say that reading is more fun on a Kindle, the digital ink is used up, instead of the LCD screen on the iPhone, even when it comes to a conclusion quite frankly can not compete in the sense of eye strain.

Work on the iPhone

Applications for work on a swarm suffer the same mistakes others iPad: you are not yet complete. Only three of them seem to lead produced by Apple's iWork. These Pages, Numbers and Keynote. In other words, a software-word processing, spreadsheets and presentations. In other words, applications, but we still have to pay about € 10 each.

Mac Aspire One A110 battery users can quickly focus in the software are available for the Macbook, iMac and Mac mini published other. Unfortunately they are not the same pleasure to use on their machines other than through manual data entry (see page 3). Another black: it is currently impossible to print these applications, this feature was not integrated with the iPhone version of the suite. But there is no alternative, because Microsoft has not updated Office and Google Docs (using Safari) is reduced using the simplest: to read IBM ThinkPad T43P battery documents.

IPhone Games

The iPhone as a gaming console? The question deserves at least invited the editors to believe in the tablet seem to function. Dozens of games are already available and is the first observation to be made about their price. This is much higher than that of games for the iPhone and iPod touch.

The more pixels are expensive, especially since these games do not take something more substantial than their smaller versions, except for the image quality. During the process, "Need for Speed: Shift" and "Mysteries of Sherlock Holmes" are perfectly playable on the iPhone. The same applies to the Scrabble published by EA, which enables multiple iPhone and use the tablet HP Pavilion dv5-1002nr battery as the Board Conclusion: The iPad is a digital book that is honest enough relegated to second place by the specialists as the Kindle. As for productivity applications and games, suffers from the tablet, especially the youth. There is no doubt that thrive in the coming weeks, ignoring dozens of applications that suffer the limitations that the iPhone seems at times. Finally, one can not help, but by the price of the games that publishers should be reduced or, even if the players want to convert to Apple Tablet HP HSTNN-UB73 to be impressed.

If the audio systems for the promise of his large continues to beat, even if the search key mantra is a perfect balance of sound.

If audio systems with the promise of noise, beat the same tone mantra librarian continue the search for impulse Cesoni Librarian Tone parfait.Fabrique by the Danish group offers even more, the rate is known at the IFA 2010 in Berlin. This wireless speaker set to a width of 360-degree sound! The Beat can occur anywhere and moved easily. It comes with a USB transmitter that an acoustic signal that the music source, PC HP Pavilion G50 battery or Mac for a range of up to 30 meters is set to play forward. Combined with an iPod, MP3 player or iPhone through a channel 30-pin, has a range of 360 degrees 10 speakers mètres.Ce will be available in Europe and the United States until early 2011 at a price of € 595. However, it is already pre-ordered.

For his part, Jean-Paul Pinto, the proposed PC for the African region, controlled all the functions of HP's new laptops and said that the election of the new strategy. "Africa is a major area of ​​investment, people are hungry for new technologies. Tunisia is the third in terms of notebook HP KS526AA battery market in 2011, shortly after Nigeria and Morocco. This trend is expected to grow by 5 % "next year, which is very encouraging," he said.

In addition, the HP Pavilion DV5 specialist said that a few lines (M) specifically designed to fully answer some of convergence at the request of the company to customers and at the same time looking for fun and multimedia-reinforced materials. built (custody, the basic structure of magnesium, spill-resistant keyboard, ...) of this area is directly inspired by the aviation industry. As proof, he said U.S. military standards (MIL-STD-810G), heavy conditions (desert dust, sand ...). The head is required if course, the reliability of the laptop, which goes "to a glass of water on the keyboard and do it before the agreement:" We sought a practical solution to various problems in finding the customer identified quality and driving performance. In addition, the HP netbook Pavilion DV6-1030CA, so complete has been reduced from the failure rate of about 16% between 2008 and 2010. "

 

15:30 Publié dans Science | Lien permanent | Commentaires (0)

How does LED power work in the past 90s

With the advent of Dell Inspiron 1525 Battery power LEDs (> 0.25 W) in the late 90s and white LEDs, optics, especially in several areas changed significantly. Therefore, the effectiveness of these components have their size and mode of administration developed and / or improving the lighting in front of the old technologies (incandescent lamps with high pressure, high and low).


The electronics associated with these new components (LED) also had to adapt and offer new solutions to this strong growth to continue the development of new optical solutions to provide and maintain, especially for the optical performance of optimal power LED maintained.


In this paper we present two modes of energy are used, the LED driving DC and pulsed current.


However, it is important to note that many applications use a voltage mode LED control, namely the electronic management system is to control the current through the diode (which must be done) is connected, but evaluate the current- tension (stable) is applied to the connections of the Dell Inspiron 1545 Battery components.


These systems are robust and have a life are often more complex review of the performance, but also significant drawbacks. Therefore, a slight increase in flux through the voltage across an LED to a significant change in the way. In addition, LEDs are arranged in the flow of light and a given current and Dell Latitude D820 Battery voltage (Vf) are different, even within the same game.


These considerations and voltage mode control will be discussed in another paper.


Two Types of food


Power supplies and other regulatory authorities provide a fixed output voltage of the output current is a constant.


The LED should go by the current, ie, the electronic control to adjust the LED current through them, are prepared independently of the number of LEDs in series, to be conducted.


The two control modes are the most common:


DC-control PWM (Pulse)


2.1. DC control


The relationship between voltage and current supplied to light emitting diode (LED) is not linear. Therefore, a small increase in the voltage across the leads to a significant increase in the flow and thus the light output.More importantly, an excessive load on the results in damage to high-speed LED current Dell Latitude D620 Battery components.Therefore, the power control is better (for a control voltage) to control the flow of light output on the one hand, and secondly, to ensure that the current in the LED does not exceed the maximum threshold of LED.


In addition, the color coordinates of white LEDs, depending on the current font. Therefore, if a driver holds the LED in parallel (ie, a control voltage), the current through each LED is different and perhaps significant differences in chromaticity coordinates between each LED.


2.2. PWM


This type of control is the most commonly used for LED (among others) because they are not very sensitive to food PWM (Pulse Width Modulation).


It maintains the functionality of "priming" (change of flux LED), most of the LED driver. All these components are integrated in many cases by an inductance, capacitance, diodes, transistors, resistors and power usually accompanied.


Influence of the third power


Many Dell Inspiron 6400 Battery studies have been conducted to show the redshift of the LED based on a semiconductor junction temperature. Thus, it was Kish and arrow (2), Nakamura (3), Tamura (4), Hong et al (5) the red LED (AlInGaP), the maximum wavelength increases linearly with the resulting combination of the temperature. In general, LED red, green and blue have a different temperature sensitivity of the union, and the red LED is the most sensitive, followed by green and blue.


The current density also affects the spectrum of the LED (match-Muller et al., 2002), but also their effectiveness.Below, we have been on the influence of the Dell Inspiron 6000 Battery power LED (high power) study focused on research in the light (Rensselaer Polytechnic Institute in New York) has made.So let's see what kind of performance won (continuous or pulsed) spectrum LED by using a different intensity.


What interests us in the case of high brightness 1W LED currently available for various applications (backlight, lighting (map lights in the aircraft (Airbus A320) in the Railways (SNCF used)).


Their technology (blue + yellow phosphor or RGB LED), the effect of food is more or less pronounced.


3.1 The technology of phosphorus


The following graphs show a white LED (blue + yellow phosphor emission), the color change of coordinates for the different types of Dell Vostro 1500 Battery supply current (DC) and pulsed (PWM).Feed the same number of LED currents (35mA to 350mA, the rated current) shows that the change in color coordinates of a LED control (CC panel) is much more pronounced (dx> 0, 05 and Dy> 0, 15) with a control pulse (Dx> Dy 0.001 to> 0.004)


In addition, the development of the deviation of the color in the opposite direction, whereby the current flow, the color temperature of the LED (cool white), while the same increase in current in pulsed mode reduces the color temperature of the LED.


It should also be noted that the two events are in the color table in the same direction.


However, in the spectra of PWM DC-look


Notice is lit for the first time, the blue tip, characteristic peak of the white LED technology with a semiconductor blue + yellow phosphorus.


This change is the opposite, as the power mode (DC or PWM), but we also see that it is very important.Also in view of the red, ie the group of 620-660 nm, there is really no significant difference in the way two different streams for use.On the contrary, we see that the biggest difference in the range 530-580nm is.In this Dell Vostro 1700 Battery area is increasing the phosphorus supply when the power is reduced to a continuous supply. This evolution of the efficiency of phosphorus has not yet been investigated, and only a few lines of study may explain the phenomenon:


A decrease in temperature, the output of phosphorus


Drift wave lengths below would also be an explanation for the improved performance or phosphorus,Also in this 530-580nm range, decreases the contribution of phosphorus with a PWM power supply along the river.An interesting thing is to compare the emission spectrum of the LED with the response of the eyeThe curve of the eye (a) nm is combined with the "peak" of the LED emission around 550. And "in this area (500-600nm), where the eye is most sensitive to the two modes of Dell Inspiron 1521 Battery power cause the greatest shift of the spectrum, according to the current application.


Therefore measure the importance of leadership style and its impact on the emission spectrum of the LED (so that the color rendering and efficiency of these LEDs).


3.2 The RGB technology


We can use the same thought about RGB LEDs.


In the diagram 2 (Diag.2a and 2b) shows the evolution of the color coordinates of the two types of power supplies (DC PWM) after the current one.


A first step is to see that this Dell Inspiron XPS GEN 2 development is not in the same direction (as for the technology blue chips + P). To monitor the development of the curve almost perpendicular to the emission of black body, while the name of a control pulse (PWM) is almost. This leads to two questions:In continuous mode, the result is an "iso-CTC" and thus the current management has an influence on the color temperature of LEDs.


The development of the coordinates of the LED color when the control pulses for the different currents that set the color temperature (CCT) for various applications (hot or cold);If we look at the phosphorus spectrum technology now in both cases (continuous and pulsed), the downward trend of the peak at about 450-470nm is confirmed.


In fact, we have realized in the case of LED fluorescent only the 500-600nm range, a significant change in the spectrum of the flows of different foods.


In contrast, the red peak (630-660nm) is very variable in its intensity (relative) in a case like the others. To check the Dell Inspiron E1705 Battery DC, the variation is greater with a stabilization "of the summit at about 640 nm red. In PWM, the variation is less pronounced, but at the same time a slight tendency of the red peak. The development between the two modes is However, change.


The last point in relation to the green wavelength, the ongoing management of knowledge and leads to an increase in the drift toward a longer wavelength when the current decreases.


Management PWM differs from the current two points: First, the contribution of the current decreases with the green, but also to be noted that this decline is centered around 515 Nm.


Moreover, the overlap of the emission spectrum of the LED with the response of the eye


We clearly see that the contribution of green in the sense of color is important (overlap of the emission spectrum from green to the sensitivity of the eye). However,Dell Vostro 1500 Battery DC, the variation of the intensity of the green woodpecker is negligible compared with the top red. At the same time, even if the differences in peak intensity red is a very important contribution to the sense of color is much lower than for the woodpecker.


In summary therefore, the DC mode, the variation of the impact of the flute in the color coordinates, while the variation of the red peak, balanced, even a small contribution due to the sensitivity of the eye, a great influence the color coordinates of the LED. Dell Precision M6500 Battery DC always drive mode when the current decreases when moving to a green light.


This is one reason why Washington green is the color of the coordinates derived from low flows.


For PWM control, the resulting color in the opposite direction of that observed in DC. Therefore, a decrease in power, a shift to the red / orange


Figure 4 shows an overview of the color changes depending on the mode and the current audit.


Conclusions and comments quarter


RGB technology is more sensitive to a change in current consumption race, especially for red wines, which are monitored to be reduced to the role of the current fluctuations.A Dell Inspiron E1505 Battery PWM control is preferred for control (CC) if you want to play in the flow of the LEDs, without many of the color.Check whether the contribution of the red and green technologies in the RGB mode DC may be difficult and expensive.


A final important point is to make clear that these studies were performed in a trap of LEDs. Other Dell Inspiron 1720 Battery LEDs in many cases, could certainly lead to slightly different values​​, show similar trends, however.