Dmx rgb flex strip .

[fasteddy]

This is a very interesting chip indeed, it is 12 channel using adaptive pulse density modulation control and has a load of features

Here is the link to the manufacturer of the MY9221 chip and details of the chip, i cant find the MY9921 so i wonder if its MY9221 or maybe it could be the 9931

http://www.my-semi.com/content/products/product_mean.aspx?id=4

and here is the attached spec sheet

 

[fasteddy]

It actually looks like it would be the MY9931, maybe the MY9921 has been supersceded

So MY9931 is a 3 channel constant current DMX 512 LED driver with cascade and differential interface, which sounds more like what would be used in the strip

The manufacturers link is http://www.my-semi.com/content/products/product_mean.aspx?id=20

and the spec sheet is attached below

 

[riri7707]

I think these DMX chips are more generic and universal for most of the controllers from the market.
Now as pricing is the war, SPI chips are more suitable and cheapest month after month for displays than DMX are today.
They are different MYxxx DMX chips available with advantages and inconvenients :
The first one MY9931 is auto adressable, so reacts like SPI , first connected, first adressed. So here these chips are more dedicated to led displays, but not for general lighting where you need to fix the adress of the fixture.
More interesting is the MY9942, for PRO lightning, where you have RGBW outputs and adressable DMX static possibility.
But regarding the price of WS2801/03/11 nothing to compare with the todays expensive DMX chips.
Great advantage: pricing of WSxxx are decreasing due to big production and variety of different modules manufacturers in CHINA...
If you still want to use MYxxx series, you can use today Ed's devices (E1.31 to DMX) or any USB to DMX device from the market... But if you take a zoom on pricing, you will see SPI chips are today the cheapest solution for our applications.
The negative and problematic point on SPI devices is the serial concept : if one chip fails somewhere, you loose all the rest of your chain. With DMX, if you loose one fixture, the rest continues to work.
Henri