Led display power and power calculation method

Source: RUI JIN

2018-04-01 09:57:32



A few days ago, we asked the friends of the weak VIP technology exchange group to ask questions related to the led display power supply. Just yesterday, other friends also asked that this problem is often encountered in weak current projects. We come together today. Learn about the display screen power and power calculation methods.

1, point spacing calculation method:
The distance from the center of each pixel to each adjacent pixel;
Each pixel can be a LED light [eg PH10(1R)],
Two LED lights [such as: PH16 (2R)], three led lights [such as: PH16 (2R1G1B)],

The pitch of P16 is: 16MM; the pitch of P20 is: 20MM; the pitch of P12 is: 12MM

2, length and height calculation method:
Point spacing × number of points = long/high
Such as: PH16 length = 16 points × 1.6cm = 25.6cm Height = 8 points × 1.6cm = 12.8cm

    PH10 length = 32 points × 1.0cm = 32cm height = 16 points × 1.0cm = 16cm;

3, screen module number calculation method:
Total area ÷ Module length ÷ Module height = Number of modules used
Such as: 10 squares of PH16 outdoor monochrome LED display using the number of modules equal to:
    10 square meters ÷0.256 meters ÷0.128 meters=305.17678≈305
More accurate calculation method: length of use module number * height of use module number = total number of modules used
Such as: 5 meters long, 2 meters high PH16 monochrome led display module number:
Long use module number = 5 meters ÷ 0.256 meters = 19.5325 ≈ 20
High use module number = 2 meters ÷ 0.128 meters = 15.625 ≈ 16 pieces

Total number of modules used = 20 x 16 = 320

4, LED display visual distance calculation method:
RGB color mixing distance Trichromatic mixing to a single color distance:
LED full-color viewing distance = pixel pitch (mm) × 500/1000

The smallest viewing distance can show the distance of the smooth image:
LED display visible distance = pixel pitch (mm) × 1000/1000

The most suitable viewing distance can be seen by the viewer:
The best viewing distance of LED display = pixel pitch (mm) × 3000/1000

The farthest viewing distance:

LED display distance of the maximum distance = screen height (m) × 30 (times)

5, LED display screen scanning method:
Scan mode: the ratio of the number of rows lit at the same time and the number of rows in the entire area within a certain display area.
Indoor single and double color is generally 1/16 scan,
Indoor full color is generally 1/8 scan.
Outdoor single color is generally 1/4 scan,
Outdoor full color is generally a static scan.

At present, the LED display screens in the market are static scanning and dynamic scanning. Static scanning is divided into static real pixels and static virtual. Dynamic scanning is also divided into dynamic real images and dynamic virtual; drive devices are generally made in China HC595, Taiwan MBI5026 Toshiba TB62726, Japan, generally has 1/2 sweep, 1/4 sweep, 1/8 sweep, and 1/16 sweep.

Give a description:
A common full-color module pixel is 16*8 (2R1G1B). If MBI5026 is used for driving, the module uses a total of:
16*8*(2+1+1)=512, MBI5026 is 16-bit chip, 512/16=32
(1) If using 32 MBI5026 chips, it is static virtual
(2) If 16 MBI5026 chips are used, dynamic 1/2 scan virtual
(3) If using 8 MBI5026 chips, it is dynamic 1/4 sweep virtual

If there are two red lights on the board
(4) With 24 MBI5026 chips, static real pixels
(5) Using 12 MBI5026 chips, which are dynamic 1/2 swept pixels
(6) With 6 MBI5026 chips, dynamic 1/4 sweep pixels

In the LED cell board, scanning methods are 1/16, 1/8, 1/4, 1/2, static. If you distinguish it?
One of the easiest ways is to count the number of LEDs on the cell board and the number of 74HC595.
Calculation method: the number of LEDs divided by the number of 74HC595 divided by 8 = a fraction of the scan
Real pixels correspond to the virtual: in simple terms,
The real pixel screen means that each of the three kinds of red, green and blue luminous tubes constituting the display screen finally participates only in the imaging of one pixel to obtain sufficient brightness.
Virtual pixels are the use of software algorithms to control each color of the light-emitting tube eventually participate in the imaging of multiple adjacent pixels, so that the use of fewer light tubes to achieve greater resolution, can display four times the resolution.

6, LED display power supply number calculation method:

The power supply is 30A and 40A; the monochrome is a 40A power supply for 8 cell boards; the dual color is a power supply for 6 cell boards;
If the full-color cell board is just like the full power at full brightness.

a, a power supply can bring a few cell board number = power supply voltage * power supply current / unit cell horizontal pixel points / cell board vertical pixel points / 0.1/2 Example: semi-outdoor P10: 5V40A power supply can be : 5*40/(32*16*0.1/0.5)=7.8 Take 8;

b. Obtain the required number of power sources based on the total power of the screen body = average total power/power of one power supply (power supply voltage*power supply current) Example: One strip screen with 12 P10 modules and 3 high P10 modules Total group: 36 modules Then the number of power required = 32*16*0.1*36*0.5/5/40=4.6 Larger (5 power supplies)

7, LED display power calculation method:

The power formula is P=UI
P stands for power, U stands for voltage, I stands for current, usually the power supply voltage we use is 5V, the power supply is 30A and 40A; monochrome is 8 unit boards and 1 40A power supply, dual color is 6 unit board and 1 power supply; The outdoor screen's power is referenced in the “product parameters” on the website, and the other side is very clear.

The following will give an example
A unit needs to have 9 square meters of indoor 5.0-color electronic screens to calculate how much power is needed most. The first to calculate the number of 40A power = 9 (0.244 * 0.488) / 6 = 12.5 = 13 power supply (to integer, in order to standard) then it is very simple, maximum power P = 13 only * 40A * 5V = 2600W.
Single lamp power = one lamp power 5V*20mA=0.1W
LED display unit board power = single lamp power * resolution (horizontal pixels * vertical pixels)/2
The maximum power of the screen = the resolution of the screen * Number of lamps per resolution * 0.1
The average screen power = screen resolution * number of lights per resolution *0.1/2
The actual power of the screen = resolution of the screen * number of lights per resolution * 0.1 / scan number (4 sweep, 2 sweep, 16 sweep, 8 sweep, static)

8, LED display brightness calculation method:
Brightness: The overall brightness of the screen is integrated by the brightness of a single lamp.
Examples are as follows:
3906 points P16 outdoor full-color 2R1PG1B (1/4 sweep), Dalian Lumei tube core, in which the red tube luminous brightness is 800mcd, the green tube luminous brightness is 2300mcd, the blue tube luminous brightness is 350mcd, which can calculate a square theory The brightness is (800*2+2300+350)*3906/1000/4=4150cd

In the clear brightness and dot density requirements, how computer single tube brightness?
The calculation method is as follows: (take two red, one green, one blue as an example)
Red LED brightness: Brightness (CD)/M2 number of dots/M2×0.3÷2
Green LED brightness: Brightness (CD)/M2/M2×0.6
Blue LED brightness: Brightness (CD)/M2 / points/M2×0.1
For example: 2500 dots per square meter, 2R1G1B, 5000 CD/M2 per square meter, then:
The brightness of the red LED is: 5000÷2500×0.3÷2=0.3
The brightness of the green LED is: 5000÷2500×0.6÷2=1.2
The brightness of the blue LED lamp is: 5000÷2500×0.1=0.2
The brightness of each pixel is: 0.3×2+1.2+0.2=2.0 CD

9, LED display screen resolution calculation method:

LED display per square resolution = 1/pixel pitch (units M)/pixel pitch (units M) Example: P16 resolution per square = 1/0.016/0.016 = 3906 DOT (dot)

10, the LED display's perspective depends on the choice of LED lamp beads

Such as indoor surface mount light: SMD0603/0805: H: 160 degrees V: 120 degrees
SMD3528 viewing angle: H: 140 degrees V: 120 degrees
Outdoor plug-in lamp DIP:dip346/546: H:110 degrees V:500 degrees

LED luminous tube wavelength range:
Red: 625-630nm
Yellow-green: 568-572nm
Pure green: 520-530nm
Blue: 460-470nm
Yellow: 585-590nm led display calculation method | led electronic display power calculation | led power calculation method

The general brightness requirements are as follows:
(1) Indoor:>800CD/M2
(2) Semi-indoor: >2000CD/M2
(3) Outdoors (South facing north): >4000CD/M2

(4) Outdoors (facing south): >8000 CD/M2

11, red, green and blue in the white composition of the brightness requirements?
The contribution of red, green, and blue in white color quality is not the same. The underlying reason is that the retinal membrane of the human eye causes different perceptions of light at different wavelengths. After a large number of experimental tests, the following approximate ratio is obtained for reference
Test design:
Simple red, green and blue brightness ratio: 3:6:1
Accurate red, green and blue brightness ratio: 3.0:5.9:1.1
What is the ratio of the length and width of the display?
Graphic screen: Determined according to the displayed content;

Video screen: generally 4:3 or close to 4:3; ideal ratio is 16:9.

12, the installation of the display requirements?
Power supply requirements: The power supply connection point should be within the screen size
220V Mains power supply, FireWire neutral line;
380V mains power supply, three fire line zero line grounding line;
Above kilowatts, the display should be depressurized to activate the device.

Communication requirements: The communication distance is defined by the length of the communication line.
The communication line must be installed with the length of the communication line used for the model of the installed display.
The communication line must not be routed with the power cable in the same line.

Installation Requirements: The display is installed horizontally and left behind is not allowed
Lifting to install up and down adjustment rod
Wall-mounting hooks must be installed before wall-mounting
Floor installation should add positioning support bolts.

In the LED industry, the correspondence between the number of points (ie, pixels) and the distance between points is as follows:
PH4=62500 points PH4.7=44300 points
PH6=27800 points PH8=15625 points
PH10=10000 points PH11.5=7500 points
PH12=6400 points PH12.5=6400 points
PH16=3906 points PH20=2500 points
PH25=1600 points PH31.25=1024 points
PH37.5=711 points PH40=625 points
PH45=495 points P50=400 points