I think they didn't preannounce because it could have taken longer than expected and people would have held orders in the meantime, which could have been a problem. [1]
Although they did do this a little bit:
> Eventually all Pico 2 products will use the A4 stepping. While the A3 stepping will not be made available to silicon customers, approximately 30,000 units of A3 inventory will be used to build Pico 2 and Pico 2 W products.
~~I'm hesistant to buy a Pico 2 or Pico 2 W right now because I might get this weird stepping that could have issues almost no one else ever sees.~~ [edit: not so much after seeing phire's comment and the bootrom-only changes in the datasheet.]
All the hardware changes and most of the bootrom changes went into A3. A4 is only a minor bootrom update.
The chance of an A3-only errata is tiny.
Right now the "rp2350 mini zero" costs me about 4.50€/unit to source on aliexpress, while the rp2040-zero costs me about 2€/unit.
So I'm probably going to stick to the rp2040 for now. I'm looking forward to eventually switching to the faster rp2350 if the price drops a little bit.
Just make sure to keep VDDIO powered when 5V is applied to any GPIO pad, otherwise the pad will be damaged. And be sure to read the relevant sections in the updated datasheet.
irdc•6mo ago
geerlingguy•6mo ago
One odd thing in the post is mention of a test A3 variant, of which 30,000 will be put on random Pico 2 and Pico 2W boards.
phire•6mo ago
It has all the hardware changes and most of the bootrom changes of A4.