As the concept of environmental protection is deeply rooted in people’s hearts, the people of the world work hard for carbon neutrality, and low -power LED display screens are becoming more and more popular.
Continuously we have introduced the advantage of low power led display, as well the general idea of the design to make the led display energy saving.
Further to this, in the 2nd knowledge page of this series, we have introduced the 2 points need to pay attention to, the power supply units’ part, and the factor of the possible overhear factor.
And now we will introduce the most important part, how to achieve the power saving of the RGB led, which is a major part of the led display board.
We know we’re telling this to the normal clients but not the scientist, so we will try to make the introduction as simple as we can, so you’d easily understand it.
All we know that the power input of the led module is 5V, but the truth is that each color led needs different power input. So, assuming we give each led 5V, the extra part of the power is actually wasted.
For example, of the 1R1G1B real pixel (including the DIP type and the SMD type), and the 2R1G1B virtual pixel led displays. The red led need 3.3V; the green, blue led need 4.2V; and the driving ic needs 4.2V.
And also, for example, the 2R1G1B real pixel led screen, no matter red, green, blue led or the driving ic, we give 4.2V.
As well, to feed the control card, also referred to as the receiving card, we use the independent power supply.
To support this solution, the options of the constant current driving ic we use are MBI5024, TB62747, TC62748 TLC59281. But the LINSN driving ic, FD9802, and the ZDEC driving ic don’t support this solution.
In essence, what we’re going to do is to reduce the voltage input to the components of the led display.
And besides the voltage, from the simple formula “Power consumption=Voltage*Current” we know the other factor to determine the power consumption is the current input.
So we need to consider the current input to the led display.
The solution is to choose the high-brightness spec LEDs. Taking the example of 1R1G1B real pixel and the 2R1G1B virtual pixel led display, we need the brightness of red led ≧1200mcd, the brightness of green led ≧2500mcd, the brightness of blue led ≧600mcd. And for the 2R1G1B real pixel, we need the red led brightness ≧600mcd, the green led brightness ≧2500mcd, the blue led brightness ≧600mcd.
The reason why we need to do that is that for the super high brightness led, we give smaller current. but could get higher or at least the same brightness with normal LEDs.
But what to be noticed is that it is not feasible to enhance the brightness of the normal led, to achieve higher brightness. If some companies do that, the power consumption of the led display would become very high, as well the lifetime of the LEDs would be reduced very much.
