The light concentration of the two is different, the rangeIt is also different: the Angle of the LED lamp bead is very small, which belongs to the relatively concentrated light, the range is very far, but the irradiation range is limited; The general Angle of the LED patch is very large, which belongs to the relatively scattered light, wide irradiation range, but the range is relatively close. The luminescence method used is different: LED lamp beads are used for discharge luminescence, and LED patches are used for cold luminescence.
Of course is the good lamp beads, the lamp beads are packaged into their own pieces, which are good for heat dissipation and light uniformity, and the light decay is slower, more durable, cob is directly packaged with the chip, the packaging method is simpler, and the price is relativeCheaper, but not as good as the beaded ones.
Good quality LED lamp imported chip, ballast has IC current protection, thickened aluminum alloy shell heat dissipation, high brightness, good heat dissipation, long life lamp characteristics. LED bulbs are composed of several to dozens of low-power (about 0.06W) LED chips or small lamp beads, and have a shell structure similar to that of traditional bulbs, which is relatively simple to use. Generally used as bathrooms, walkways, night lights and other places where the brightness does not need to be too high and needs to be lit for a long time.
LED lamp bead. High-power LED lights generally use 1W high-power LEDThe control circuit of the part controls the size of the output current, so that the LED lamp produces different brightness output. The circuit design of the LED driver chip is generally composed of the following parts: Input voltage control: This part is responsible for stabilizing the input voltage and ensuring that the driver chip can work normally. Control circuit: This part is responsible for controlling the brightness of the LED lamp, and the output current can be adjusted according to the demand.
The working principle of the led driver ic: the chip contains a constant current generation circuit, which can set the output constant current value through an external resistor. Through the enable end of the chip, the switching time of the output channel can be controlled and the frequency can be switchedRates up to 1 megahertz (1mhz). The current output response is extremely fast, supporting applications with high color level changes and high picture refresh rate. Built-in open circuit detection, overheat outage, and overcurrent protection greatly improve the reliability of the application system.
led driver Principle LED (LightEmittingDiode) driver is a kind of electronic circuit used to drive LED. Leds are light-emitting diodes that require the right current and voltage to work properly. The role of the LED driver is to provide the current and voltage required by the LED to ensure the normal operation of the LED. LEThe D driver usually consists of the following components: Input voltage regulation circuit: The role of this part is to regulate the power supply voltage to the voltage required by the LED.
The principle of the LED light driver is to control the brightness of the LED by controlling the current. Leds require a steady current to maintain their brightness, rather than adjusting the voltage to control the brightness. Therefore, the driver controls the brightness of the LED by adjusting the current. This can be achieved by using current limiting elements such as resistors or current sources.
1, LED chip type LPE: LiquidPhaseEpitaxy (liquid phase epitaxy) GaP/GaP. VPE: VaporPhaseEpitaxy (Gas phase epitaxy) GaAsP/GaAs.
2, LED lamps use low-voltage power supply, in this case, the general chip, the key is not the chip, is the heat dissipation design of the lamp and the quality of the constant current power supply. The power supply voltage used by the chip is generally DC low voltage, constant current appliances are very critical, if the quality of the constant current power supply is no problem, then testUnder the temperature of the lamp, solve the heat dissipation, the other is no problem. But it is best not to use DC12V input voltage, the circuit board is not good design.
3, LED chip is characterized by power integrated chips, generally used in floodlights, in the field of surface light source is very advantageous. LED chip Corui is characterized by point light source, brand influence, lumen, and other average performance is very good.
4, LED (LightEmittingDiode) chip is a solid-state semiconductor device, it can directly convert electricity into light. LEDThe heart of the chip is a semiconductor chip, one end of the chip is attached to a bracket, one end is a negative electrode, and the other end is connected to the positive electrode of the power supply, so that the entire chip is encapsulated in epoxy resin.
5, LED display driver chip type What LED driver chip can be divided into general purpose chip and special chip two. The so-called universal chip, the chip itself is not specifically designed for LED, but some logic chips with some logic functions of the LED display (such as series-and-shift registers). The special chip refers to the driver chip designed specifically for the LED display according to the LED luminous characteristics.
6, good reliability. (3) Widely used. (4) High safety. (5) Long life. How to judge: The price of led chip: In general, the price of the lower chip is higher than the price of the wafer, high-power led chip is certainly higher than the low-power led chip, the import is higher than the domestic, and the source price of the import is reduced from Japan, the United States and Taiwan.
The chip refers to the epitaxy for processing, its main purpose is to epitaxyAdd electrodes to facilitate packaging and application. The main material of the chip is monocrystalline silicon, which is still GaN material. It can be said that epitaxy is the raw material of the chip, and the chip is to add electrodes on the basis of epitaxy (some chips also do passivation films, mirrors, and so on).
Upper bracket - point base glue - chip - bake solidification - gold wire bonding - point fluorescent glue - shell filling - test - light color sorting - packaging (high-power LED).
LED chip manufacturing process: epitaxial sheet → cleaning → transparent electrode layer plating → transparent electrode graphic lithography → corrosion → degluing → platform graphic lithography → dryEtching → de-gluing → annealing →SiO2 deposition → window pattern lithography →SiO2 corrosion → De-gluing → N-pole pattern lithography → Pre-cleaning → coating → stripping → annealing → P-pole pattern lithography → coating → stripping → Grinding → cutting → chip → finished product testing.