Does anyone here have experience using DIP or SOP-8 WS2811 chips to drive "dumb"

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Does anyone here have experience using DIP or SOP-8 WS2811 chips to drive “dumb” common-anode RGB strip?

I’m considering a circuit like the one here which will allow the WS2811’s constant-current PWM to drive the gate of a MOSFET which can PWM around two metres of RGB strip. It seems it will work in theory, but as I don’t have any WS2811 chips on me (until my shipment of RGB strip and DIP WS2811 chips arrives), I can’t test it.

If this doesn’t work, I’ll fall back to the PWM pins on the controller, but the ATMega2560 only has 16, enough to drive 5 “pixels”.

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It’s totally doable. This (pre-built) board does just that: has one driver chip and then three power transistors for driving a ‘dumb’ strip.
http://www.dxsoul.com/product/full-color-rgb-led-strip-driver-module-for-arduino-blue-black-901314667#.VQ9xZIr3anM

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Those aren’t too bad. I found a source for those outside the U.S.: http://www.aliexpress.com/store/product/Full-color-RGB-LED-Strip-Driver-Module-For-Arduino-Can-Be-Cascaded-Blue-Black-Hot-New/1199788_1831927656.html

Sadly those wouldn’t arrive in time for the project I’m working on, so it’s stripboard time for me.

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DX and Aliexpress are both outside the US. Likely same sourced manufacturer as well.

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If you want to increase the number of PWM outputs you have, you can always use something like a TLC5940 to expand, just in case everything else falls through

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The thing about a TLC5940 is that it’s yet another current sink. I’m trying to drive 90+ LEDs as a single “pixel” – using 12V RGB strip this is (30 x 20mA =) 600mA. The TLC5940 only handles 120mA.

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@Ashley_M_Kirchner_No
FYI, the DXSoul site wouldn’t let me choose shipping to Australia in the first place.

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yes! I ended up using an appropriate PNP per channel as described in this thread: http://forum.arduino.cc/index.php?topic=257956.0

This guy in the other link used the recommended circuit from the WS2811 datasheet. http://thepixelheart.github.io/Ordering-Prototypes/

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See also this module from FastLED user @Garrett_Mace and @macetech .
http://macetech.com/store/index.php?main_page=product_info&cPath=12&products_id=57
( Looks pretty serious… but then again, I’ve heard that desert thing can be somewhat hard on electronics. http://wiki.orbswarm.com/index.php?title=Building_Electronics_and_Robots_for_the_Desert )

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For my current project (which is in Australia and will never make it to TTITD) I’ve just thrown the MOSFETs onto some veroboard. My limited understanding of analog electronics coupled with a time constraint meant that I couldn’t get the bridge actually working in time, so I had to fall back to a simpler plan (now using 12 of the PWM pins of an Arduino Mega and driving the FET gates from those).

Which seems to work just fine, although I haven’t tested the longer lines yet; hopefully the voltage doesn’t sag below the FETs’ threshold.