Lighted diodes, known as leds, are commonly used luminescence devices that release energy from electron and hollow complexes and are widely used in lighting。
Lighted diodes can efficiently convert electrical energy into light energy and have a wide range of applications in modern society, such as lighting, tablet displays, medical devices, etc。
Thermal dispersion of the luminous diode encapsulation
In semiconductor lighting devices, high-power, high-lighted leds are usually used as a source of light, and when electrical currents are used in the light diodes, electrical power and hollows are directly combined, thus releasing energy light, which has the advantage of low power consumption and long operational life, and is widely used in lighting。
However, power density on led chips is very high because of the current low efficiency of pv conversion and the large proportion of it is converted to heat. Large power density also places high demands on the dissipation of components, and the problem of containment of bulk heat in luminous diodes has become a major problem affecting their industrial development。
Thermal cooling method
Led dispersors generally take these forms:
1. Thermally transmitted metals or dispersive fin blades are used in conjunction with led envelopes。
2. Forced dispersion of fans。
3. Sets liquid dissipation heat in containment packages。
4. Thermal tubes are combined in packagings and thermal energy can be absorbed or distributed using the work media in the heat tubes when they vary。
Motivation
Led design
Design factor: 1. Luminous diodes at voltage relief at 2. Luminous diodes at work
The first requirement to meet the power supply must be greater than 3. 3 volts, and in order for the diode to have a current size of 10 ma at work, a chain of electrical resistance on the lighted diode would be required, as shown below
The effect of the resistance here is to limit the flow to 10ma。
Parameters for power supply at led
The nature of the choice of direct current power is the type of voltage and current power
Power source type: keep the voltage constant and the voltage source can be disabled。
Power source type: keep current constant, unrelated to load, and keep circuits open, once the opening of the circuit is punctured by the constant current maintenance of the current in polar air at high pressure。
In this application, it is not possible for the first luminous diode to be connected to the current circuit, but only to be combined, with short circuits being cut off while the luminous diode is working, short circuits closed, and the power is not ideal, there is internal resistance and the current must be routed, and this is not appropriate from the point of view of energy consumption。
It is not possible for a power source of each size, like a currency face, to be supplied with a direct current voltage source, with the main specifications for the application being 3. 3 v, 5 v, 12 v, 24 v, 48 v direct current voltage source, which already has 3. 3 v due to the conductive voltage reduction of the diode, with a view to reducing power consumption。
Resisting resistance values and their power
Backway current i = 10ma with luminous diodes having a positive guidance condulsion pressure of 3. 3 v, a power source of 5 v and a resistance value of 170 eue with a power of 0. 017 w。
Access to 5v current voltage sources
Here's an lm7805 steady-pressure module with a lighted backway for the diode. Icon
The range of voltage selection on vin is between 12 and 25 volts, with the commonly used 12 volts and 24 volts used to calculate lm7805 power of 0. 2w at 24 volts to ensure that work does not heat up, and if the pressure pressure of the pressure module is too low, it can be heat-intensive, it can be heat-dispersed, or it can use several voltage modules, whether the working or load current of the voltage source consisting of multiple voltage modules。
