Hi, I’m interested to know if the pre-level shifted clock and data signals are available on any of the pads on the bottom of the Pixelblaze Pico Plus?
No, but the main edge connection is castellated and can be soldered to a board.
Thanks for the reply. We were potentially looking at integrating the Pixel Blaze Pico+ as an option in something else we’re building. We’re driving LEDs from another ESP32.Hmm so that means we will need to put the PixelBlaze Pico+ clock and data through a 5 V MUX rather than a 3.3 V MUX so that the data and clock lines can either be controlled by the PixelBlaze or by our hardware.
If you want 3.3v data, you can use a resistor voltage divider to drop the 5v down.
If it’s a digital mux it should buffer a high impedance signal so you can use fairly high value resistors. A few k or so, like 1k then 2k to gnd.
If analog mux you can use lower value resistors so the signal out to LEDs isn’t too weak. PB has 100 ohms already. Something like 200 ohms to gnd would drop it to 2/3 and get 3.33v.
Some general info/advice for LEDs:
Some addressable LEDs (especially older revs) do not like 3.3v data when powered at 5v. LEDs with CMOS inputs want 0.7Vdd, at 5v power that’s 3.5v so 3.3v signal is marginal and can lead to flickering.
Many newer LEDs have been upgraded to handle 3.3v data reliably, but not all of them. WS2816 for example is not happy at 3.3v data.
If you know the LED ahead of time you can verify it in the datasheet, but for broad compatibility 5v data is more universal, which is why PB has level shifters to send 5v data.
Most addressable LEDs can run fine at 3.3v for power but it’s usually outside of their rated range. Some may slightly drop blue/green response. But if you power them at 3.3v then 3.3v data is fine.
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Thank you for the reply. I think what we’ve decided to do is put a level shifter on our other ESP32 and then use a 5 V MUX out to the LED’s.