The scanning mode of LED display confused many people, what’s does it work? And what’s this affect for LED screen? Here give you detail information:
Mean LED is driven by IC
Mean LED is off
Each drive IC have 16 pins, and can drive 16 LED chip at the most. Static drive mode means all the LEDs on the LED module are driven by IC at any time, like following image:
1/12 scan mode, means 1/12 LEDs on the module are driven by IC at one time, and next time there are other 1/12 LEDs are driven.
1/6 scan mode, means 1/6 LEDs on the module are driven by IC at one time, and next time there are other 1/6 LEDs are driven.
Note: Because the scan mode change scan lines very fast, and can’t be distinguished by human eyes, so in visually, we feel the LEDs are light on all the time, but in fact, the scan mode have LEDs off when we see it.
So, the low scan mode can save drive IC, and save cost. But what’s it affect for the LED screen?
1) Brightness: The high scan with more LEDs light on at one time, so the brightness are higher than lower scan mode, in theory, for the same LED display, static scan is double brightness of 1/2 scan, and 1/4 scan is double brightness of 1/8 scan. But this is not absolute formula, because sometime there don’t need so much brightness, and will low down the current, and finally cut the brightness.
2) Refresh rate: Usually lower scan with lower refresh rate than the higher scan. And this is not applicable like the multiple formula as brightness, because the refresh rate mainly depend on the PCB design.
3) Power consume: In theory, the higher scan, the higher power, this is applicable multiple formula, for example 1/5 scan is double power consume of 1/10 scan. Also, it restrict by the current, factories may reduce current and finally reduce power and brightness.
Therefore, it’s very important to choose a reasonable scan mode for LED display, not the higher the better, also not converse. It need based on the brightness, power, refresh rate and cost, finally design a good LED screen.