Trying to understand powering first microcontroller ATSAMD51

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I'm trying to understand powering my first microcontroller (coming from simpler chips with 1 power input and one ground), I'm wanting to buy the ATSAMD51 series (specifically the ATSAMD51J20A-AU which is 64-pins)

 

Looking through the data sheet it's far more complicated than I anticipated with 7 power pins and 5 ground pins. I would assume I just provide equal power to all power pins (My target voltage is 3.3 volts) but the schematic checklist part of the manual details it's more complicated and that different pins require different setup with an arrangement of resistors, capacitors, inductors, and wiring, one pin appears to require half the voltage. They provide an example image that's just as confusing

 

Example of a Linear power setup which is what I'm wanting out of the 3 options they provide and as stated above my setup is 3.3v

  • I assume VDDIO is referring to all the VDDIOA pins because VDDIOB has to have half the voltage and I assume it's for all the VDDIOB pins
  • I'm not entirely sure which VDDIO pins are VDDIOA and VDDIOB
  • Why is the power supply being wired to ground through capacitors, aren't the power and ground suppose to be separate so they're not mixed and crossed
  • GNDANA doesn't show up on the pinout list as to what pin number it is but I can see there is a GNDANA pin

 

I guess I'm really confused and I know this is all pretty noob questions but any help would be great

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Wait.... Digging deeper through the manual it looks like VDDIOB is only on the 100 and 128 pin models. So all this time I've been trying to figure out that part of the image there's been no vddiob on the chip I want and the image is generalizing across all models. So that also means I don't have to worry with voltage halving and whatnot. Not having a VDDIOB greatly simplifies all of this much more than the image makes it out to be.

 

Or am I understanding this wrong?

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It's not very complicated, how did you come up with the "half the voltage" requirement?

Consider looking at an existing design like https://learn.adafruit.com/adafruit-metro-m4-express-featuring-atsamd51/downloads

/Lars

 

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I had misread the "VDDIOB" requirement to need to be half the power requirement but it doesn't matter anyways because I eventually realized the 64-pin chip doesn't have a VDDIOB which simplifies things in general and I eventually figured it all out.

 

I've posted a new topic on a 120MHz speed though and I could use your help if your interested, thanks for your answer to this ^_^