1. Have to drive DP1903, 100 lights, each of 100leds , in sync as they glow

So that all looks same.



2. I tried making different MCU for each individual DP1903 leight(100 led in each). But after sometime they all go bit out of sync. Even if all MCU power is turn on at same time. The difference is low, but noticeable.



3. One solution I think if, I drive all DP1903 lights with single MCU. I think what will happen is all will be in sync as they glow, as driving MCU is only one.

is ther any buffer/drive available by which it can be done.



4. Any other solution

 

How have you connected these up? Are all DP1903 LEDs in series as the one string?
Please explain in more detail.

 

100 DP1903 in parallel. Each parallel DP1903 had 100 leds in series.
100 parallel Dp1903 to be driven by single MCU

 

A DP1903 cannot drive 100 LEDs so here is the first part of my confusion.
Please draw a circuit of your setup.
If you are going to have all the LEDs working together, all the same colour and brightness, a DP1903 setup is not the way to go. Just use PWM driving a FET for each colour.

 

I think I havent put my query right.

Suppose there are 100 individual DP1903. I have to drive them in parallel with a single MCU, so that when data reaches to 100 parallel DP1903, it is sync.

What buffer I have to place beteen one MCU out & each input of 100 parallel DP1903

 

If you are going to use 100 DP1903 chips like that, all the LEDs will be the same. It will be easier and a lot cheaper to run your 1000 LEDs via PWM and FETs.
Still, running the 100 DP1903 chips could be done with an octal line driver. So the micro drives the 8 inputs of the line driver, and each output drives 1/8th of the DP1903 chips. You may need to run a couple of these chips but fanning the drive out will be the way, not driving all 100 together on one pin.
But still, why do you want to use these LED driver chips if you are not going to make use of the individual LED control mode?

 

Cannot find a datasheet, but found this -

https://www.avrfreaks.net/forum/understanding-dp1903-timing-ws2811-variant

So it looks like a one wire device ? Perfect synchronicity not possible because data
is being sampled by async clocks. But that might be a non issue depending on
human eye characteristics and actual latency string to string.

Regards, Dana.

 

Looked at the datasheet for what I believe is a closely related variant, and there's a 500 nanosecond delay from data in to data out on each chip, so 100 in a row would equal 50 microseconds from first to last.

https://cdn-shop.adafruit.com/product-files/1138/SK6812+LED+datasheet+.pdf

So, although these chips are overkill, you should be able to string 100 in series with each other (no buffers or splitters, and just one microcontroller) and have a delay that's at most 1/20th of one millisecond.