Answering questions about GS8208

queena

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I see some questions from Alan ,and i find out the answer

1. If you lose 1 led out of the RGB does the pixel go dark with no colours shown or does it just show the other 2 colours.
  • Once the pixel show with the dead-colour, the the pixel will go dark with no colours shown . For example, if R is dead, G/B/G+B can be displayed normally, R/R+B/R+G/R+G+B will be off, and the pixel goes dark will instead the original color mixing error.

2. With the data backup does the next pixel process it's own data or does it process the data from the previous "dead" pixel. In short if you have a matrix or similar do the lines stay in sync with 1 pixel missing or does the missing pixel cause everything downstream to shift 1 pixel.
  • This problem is considered when designing, the next pixel will get its own data display, so there will be no data offset. Some cheap solutions do cause data offset, so we will explain the working principle of breakpoint transmission later.

3. On power up how long is it before the internal test function starts up and does it require the data signal to be open circuit, 0V or 5V to start the test signal.
  • Normally it is 500ms, as long as there is no correct signal, it will start, 0V/5V all can be used.

4. Related to 3. Will the pixels resort to a test signal if they don't get a valid WS281x type signal for a given amount of time. This can be important if pixel controllers don't send data out at all times.
  • Yes, you must ensure that the controller sends data all the time, otherwise the IC enters the automatic mode.

5. Does each chip produce the test signal or does the first pixel that doesn't see data and it gets sent out along the data lines?
  • The first pixel will send Auto-Control data when it doesn't see data .

6. If the first pixel produces the test signal is it sent out in a WS281x type signal?
  • Yes, but it is the special encoding format of the chip itself.

7. The GS runs off the same data signal as WS281x. Can the GS be daisy chained in with WS281x pixels with the WS ones before and/or after? WorldSemi screwed around with their WS2811 timing and I was wondering if that has any effect on GS pixels.
  • Under some kinds of controller timing, GS can be connected in series behind the WS chip, but it is suggested not to connect in series to Keep data stable.

8. If you have the RGB brightness all set to 5 (out of 255) for instance is the current 18mA or closer to 1mA
  • The current closer to 1mA if you set the RGB brightness to 5
 
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AAH

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Thanks for answering all those questions.
Most of the answers were a good result.
I had hoped that the test signal was produced in the 1st pixel and that it was a WS281x compatible signal. I was thinking that I could possibly use 1 of the pixel IC's as a test signal generator on a few of my boards.
 
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