CHALLENGES DESIGN OF SWITCHING LED ELECTRONIC DIAGRAM

CHALLENGES DESIGN OF SWITCHING LED ELECTRONIC DIAGRAM

The LED WEBENCH® online design environment predicts and simulates the response of an LED to constant current while taking into account several potential design parameters that are new to designers of traditional switching regulators.

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More And More White LED lights For Indoor Lighting

With the constant progress of LED technology, LED light gradually develop from the flags and show the development stage to lighting applications, and its long life, high efficiency and energy saving features have been recognized, white LED opened a window for "green light" a White LED interior lighting,  the indoor applications
 are being more and more increasingly widely used.
Many advantages of white LED interior lighting with white light LED used in a number of advantages. First, LEDs brightness and light color adjustable interior lighting to meet the requirements of color, lighting scenarios in the development of the market, with traditional light sources can not match advantage. Second, LED easy to dynamically control, in accordance with the needs of the user control the default cluster, and in some occasions require programming skills, can provide a reasonable solution for the intelligent management of indoor lighting and convenient. Third, LED compact, more decorative features, with the buildings by lighting the organic integration of default, to "see the light but not light" results. Fourth, LED, long life, no mercury, in line with the national "energy saving and emission reduction" policy requirements. Fifth, LED beam angle is within the absolute directional radiation for spotlights, downlights and other lamps, will help improve the next shot lumen ratio.
With the LED technology upgrade, show the effectiveness of power, cost reduction, both in the international market or domestic market, LED has begun to enter the business or department according to Ming Shi home lighting market, showing a good momentum of development. Broad application prospects in the indoor lighting LED prices are still very expensive at this stage, but because LED lamps have higher luminous efficiency, power loss can be cutting costs, while a longer life, can reduce replacement and maintenance expense, therefore, consider the development of white LED interior lighting direction, relative to traditional lighting methods, white LED light is the most important return on investment considerations.
After analysis shows that, compared to incandescent lamps, LED lamps of the investment recovery period is 1.7 years to 3.4 years; compared to halogen lamps, LED lamps of the investment recovery period is 1.7 years to 3.5 years. Thus, replacing incandescent and halogen lamps, LED controller, the application of white LED has a very attractive rate of return on investment. Compared to compact fluorescent lamps, the department applications, LED lamp investment recovery period is 4.5 years to 6.2 years; compared to straight tube fluorescent lamps and metal halide lamps, LED lamps do not have good performance of the investment payback period.
Although white LED lighting in the room to expand the application areas share constantly, but there are faced with many challenges. LED lights only need to keep dependents chip or package the relevant parts of the performance, but more of a focus on LED lighting, the composition of electronic technology, thermal management and optical technology.

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Roma has developed a small E17 LED Light Bulb

Roma has developed a small LED bulb "LDA4L-G-E17" can support E17 lamp holder, compare with the original LED bulbs such as 12 volt LED lights, new products reduce the size of the power part, the shade of the hemispherical shape is more nearly spherical. LED light source module use the COB construct without mirror, the shape almost identical to  old-fashioned small krypton bulb to achieve 180°light distribution angle.

Prior to the disadvantage of small LED bulb is less luminous part of the light distribution angle narrow, dark horizontal and supply side. The brightness of the new product is equivalent to a 25W mini krypton bulb. The shade is made of the proliferation of Roma self-developed material that can be issued does not point to the warmth of light. The bulb the total luminous flux of 265lm, the power consumption of 4W. The light color than incandescent light color. Design life (the luminous flux dropped to 70% of the initial time) is approximately 40,000 hours. Pricing is open, expect the actual price of less than 2000 yen.

By the way, I konw where to buy the LED lighting such as LED light and best led flashlight at low price,

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Programmable LED Flashers

These circuits were designed on request. Both feature a flashing LED that, after a preset number of flashes will illuminate steadily until P1 (Reset) will be pressed.
Parts:

R1______________10K 1/4W Resistor
R2_______________1M 1/4W Resistor
R3_______________1K 1/4W Resistor (See Notes)
C1_______________4µ7 25V Electrolytic Capacitor
C2______________10nF 63V Polyester Capacitor
D1___________1N4148 75V 150mA Diode
D2______________LED (Any dimension, shape or color)
IC1____________4060 14 stage ripple counter and oscillator IC
P1_____________SPST Pushbutton
SW1____________SPST Toggle or Slider Switch

B1______________3V to 15V Battery or dc power source (See Notes)
uses only one chip and can be useful if a not very precise number of flashes of the LED is needed before reverting to the steady-on state. In fact, connecting D1 Anode to different output pins of the IC, the steady-on state of the LED will be obtained after 2, 4, 8, 16 flashes and so on.
Connecting D1 Anode as shown, the LED will start flashing at about two times per second after power-on and will revert to the steady state after 8 flashes. P1 resets the circuit and C1 automatically resets IC at power-on.
Connecting D1 Anode to pin #13 of IC1 the flashes will be 4; to pin #1 will be 16 etc.
The flashing frequency of the LED can be varied by changing the values of R2 and/or C2.

Notes:

* Circuits were tested at 9V supply, but they might work in the 3 - 15V dc supply range.
* The LED current limiting resistor value was calculated for 9 - 12V supply and should be changed to suit different supply voltages.

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LED Christmas Star

This circuit can be used to construct an attractive Christmas Star. When we switch on this circuit, the brightness of lamp L1 gradually increases. When it reaches the maximum brightness level, the brightness starts decreasing gradually. And when it reaches the minimum brightness level, it again increases automatically. This cycle repeats. The increase and decrease of brightness of bulb L1 depends on the charging and discharging of capacitor C3. When the output of IC1 is high, capacitor C3 starts discharging and consequently the brightness of lamp L1 decreases. IC2 is an opto-isolator whereas IC1 is configured as an astable multivibrator. The frequency of IC1 can be changed by varying the value of resistor R2 or the value of capacitor C1.

Remember that when you vary the frequency of IC1, you should also vary the values of resistors R3 and R4 correspondingly for better performance. The minimum brightness level of lamp L1 can be changed by adjusting potentiometer VR1. If the brightness of the lamp L1 does not reach a reasonable brightness level, or if the lamp seems to remain in maximum brightness level (watch for a minute), increase the in-circuit resistance of potmeter VR1. If in-circuit resistance of potmeter VR1 is too high, the lamp may flicker in its minimum brightness region, or the lamp may remain in off state for a long time. In such cases, decrease the resistance of potmeter VR1 till the brightness of lamp L1 smoothly increases and decreases. When supply voltage varies, you have to adjust potmeter VR1 as stated above, for proper performance of the circuit. A triac such as BT136 can be used in place of the SCR in this circuit. Caution: While adjusting potmeter VR1, care should be taken to avoid electrical shock.

 

 

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