LED lighting

- 2021-07-28-

How much do you know about LED lights?
1. LED classification
According to welding method: divided into SMD and DIP
SMD has 3528, 3020, 5050, etc., the size is such as: 3528 is the LED lamp. The outer size is length 35 and width 28
1W general chip size is 30*30mil, 38*38mil, 40*40mil, 1mil=0.0254mm

2. Color and wavelength
Visible light range: 300~700 nm
Red wavelength 620~625 nm
Yellow wavelength 590~595nm
Blue wavelength 475~480nm
Green wavelength 520~525nm
Infrared wavelength 680nm
Fluorescent lamp, incandescent lamp is full wavelength

Examples of invisible light:
The fiber is divided into three sections, wavelength 980nm, 1310nm, 1550nm

White LED architecture:
White LED is blue Chip plus yellow phosphor
The warm white LED is a blue Chip with yellow and red phosphors
Positive white temperature 5700~6300 °K【6000 °K】
Warm white temperature 2800~3200 °K【3000 °K】
White light is mostly defined by color temperature (more strictly defined as coordinate definition):
Definition of color temperature: the color change of a piece of iron burning red
Conversion of °K to °C: °K=273+°C

3. Voltage vf
Red yellow :1.8~2.5V
Blue green white: 2.8~3.6
The general standard power supply voltage output is 5V, 12V, 24V, 38V

LED current:
1W LED=320mA~350mA 3W LED=700mA
Low power is 18mA and not more than 20mA
Power calculation method W=IV

LED architecture:
LED silver glue: silver powder + epoxy resin
LED gold wire: Φ0.9/1.2 mil gold wire or aluminum wire
Bonding machine: fixed chip
Stringing machine: Kind of golden ball and golden thread
LED light gold wire power: power is not less than 9g


Definition of brightness:
Luminous flux/beam
lumen / LM
The total amount of light emitted by the light source
luminous flux


Illuminance
E
The luminous flux per unit area on a certain working surface (the illuminated object) is bright
illumination
lux
E = I cos / D2
brightness
I
The luminous intensity of a light source in a certain direction
luminous intensity
Candlelight cd

Brightness
B
The luminosity of a light source in a certain direction is divided by the projected area of the light source in that direction
brightness
nit
B = cd / m2

LED lumen value:
Red 40~45 Yellow 35~40 Blue 25~30 Green 45~55 White 90~110 Warm white 80~90 3528: 4~6 5050 or 5060: 18~20

Large crystalline semiconductor production companies:
Nichia
Osram
Cree
Toyota
Philiip clumiled
Hancheng
Samsung

4. the circuit
IC: LM317 voltage is 2.25V, LM1117 voltage is 1.25V
resistance:
680 = 680Ω current 18mA
3R9 =3.9Ω current 320mA [voltage 1.248V]
3R6 =3.6Ω current 350mA [voltage 1.26V]
Standard full-color six colors:
R, RG, G, GB, B, BR

5. the system
1. Display system
2. DMX512 [refers to 512 channles]
Features of the display system:
A. Many control points
B. Small current
C. Low price
Features of DMX512 system:
A, less control points
B. Large current
C, the price is high
D, universal

Composition structure: host + decoder + lamps

Factors affecting prices:
1. Color
2. Change method
3. Indoor or outdoor use
4. Voltage
5. Number of LEDs
6. Shape
7. Lighting height

Lamp interface: screw head E11, E17
Two-pin MR16 OR GU5.3 Mirror Reflector 16 x 1/8 inch diameter
GU10