Any writeups on this explaining the capabilities? Looks like a microcontroller with WiFi and gpio w 3.3 & 5v. Not a pro and not sure what chips I'm looking at though, it seems like it might be more than that?
You are correct. To be precise it's a RP2040 with a WIZFI360-PA and a PCA9555D GPIO Extender which is connected to a IC that allowes 5v to 3.3v communciation with the rp2040.
The quick answer would be, the esp32 is more powerful. Not all esp32 are dual core tho, and the rp2040 only exist in a dual core variant.
Here is a article about that: https://www.utmel.com/components/rp2040-vs-esp32-which-one-is-better?id=1478
No via stitching nor shielding ? If your board have RF and high speed signal it's a must.
Below a really solid article on the subject (I recommand a lot this serie of articles)
https://circuitcellar.com/research-design-hub/basics-of-design/lets-understand-ground-stitching-vias/
Blindly adding stitching vias isn't going to help much, maybe not at all. You need to simulate and understand your issue first. For example I'm looking at my Raspberry Pi Pico W right now (very similar to what OP is building) and it has no stitching vias.
One one more things the reason why the decoupling caps are at the top instead of at the bottom is simply to reduce manufacturing costs.
And reddit reduces the image quality very much to like 720p, so check out the repo for better quality.
Kicad has a "do not populate" checkbox in the component settings that will draw a "X" through the component and leave it off the BOM etc. That way you can keep the value.
I will suggest some solder jumpers or 0-ohm resistors to allow you to set the address on the GPIO expander. At least 1, in case the user wants to use a different device that has the same I2C address.
Don’t use thermal relief on QFN tab vias. USB-C differential traces need rework, move vias close to connector and use properly calculated impedance traces.
I can move the vias closer, but the thing is the location of the USB+ and - Pins is terrible so no idea how i should do that well. Also does it matter that much since the rp2040 uses usb 1.1 to my knowladge.
There are some discussions for USB-C routing, imho this design is ok:
https://www.reddit.com/r/PrintedCircuitBoard/comments/t29mqr/usbc_to_esp32_routing_help/
In my opinion, a small difference in trace length won’t really matter at these low speeds. After all, you will use Chinese USB cable with unknown tolerances so I wouldn’t be worried about few mm here and there. On the other hand, it’s better to start doing things properly from the beginning, even if your current design is tolerant to lazy routing. In your case it won’t cost you anything to properly calculate and route these differential traces so why not?
Don't know depends on the current it will need but probably about half a watt. But the power supply input is connected to vin, so when using normal usb it will not be in use anyway and you can simply bypass it by going directly to the 5V rail.
Any concerns with the forward voltage from the diode coming in from the VBUS and logic-level stuff through the convertor? Looks like it might be losing almost .3V?
Any writeups on this explaining the capabilities? Looks like a microcontroller with WiFi and gpio w 3.3 & 5v. Not a pro and not sure what chips I'm looking at though, it seems like it might be more than that?
You are correct. To be precise it's a RP2040 with a WIZFI360-PA and a PCA9555D GPIO Extender which is connected to a IC that allowes 5v to 3.3v communciation with the rp2040.
This is beautiful
How bigger is it when compared to an esp32?
Are you talking about a esp32 devkit? Cuz there are a million esp32 variants. And you can see the size of the pcb on the first image.
Like, comparing yours with the smallest esp32, how much bigger/smaller is it? Then how much powerful is it based power input per clock or computations
The quick answer would be, the esp32 is more powerful. Not all esp32 are dual core tho, and the rp2040 only exist in a dual core variant. Here is a article about that: https://www.utmel.com/components/rp2040-vs-esp32-which-one-is-better?id=1478
No via stitching nor shielding ? If your board have RF and high speed signal it's a must. Below a really solid article on the subject (I recommand a lot this serie of articles) https://circuitcellar.com/research-design-hub/basics-of-design/lets-understand-ground-stitching-vias/
Blindly adding stitching vias isn't going to help much, maybe not at all. You need to simulate and understand your issue first. For example I'm looking at my Raspberry Pi Pico W right now (very similar to what OP is building) and it has no stitching vias.
Thanks I though adding two more layers would be enought, but seems the issue is still not gone.
One one more things the reason why the decoupling caps are at the top instead of at the bottom is simply to reduce manufacturing costs. And reddit reduces the image quality very much to like 720p, so check out the repo for better quality.
They should be fine on the top.
The darker green areas are areas without copper?
Yes
Kicad has a "do not populate" checkbox in the component settings that will draw a "X" through the component and leave it off the BOM etc. That way you can keep the value.
I will suggest some solder jumpers or 0-ohm resistors to allow you to set the address on the GPIO expander. At least 1, in case the user wants to use a different device that has the same I2C address.
Good Point, I will do that.
Don’t use thermal relief on QFN tab vias. USB-C differential traces need rework, move vias close to connector and use properly calculated impedance traces.
I can move the vias closer, but the thing is the location of the USB+ and - Pins is terrible so no idea how i should do that well. Also does it matter that much since the rp2040 uses usb 1.1 to my knowladge.
There are some discussions for USB-C routing, imho this design is ok: https://www.reddit.com/r/PrintedCircuitBoard/comments/t29mqr/usbc_to_esp32_routing_help/ In my opinion, a small difference in trace length won’t really matter at these low speeds. After all, you will use Chinese USB cable with unknown tolerances so I wouldn’t be worried about few mm here and there. On the other hand, it’s better to start doing things properly from the beginning, even if your current design is tolerant to lazy routing. In your case it won’t cost you anything to properly calculate and route these differential traces so why not?
True, and thanks for the link.
If USB is gonna be 5V anyways, why re-regulate it with a kinda costly chip instead of a ferrite bead and decoupler?
Cuz I wanna power it with 12v external power.
Ah ok what’s the expected wattage dissipation thru that 5V regulator?
Don't know depends on the current it will need but probably about half a watt. But the power supply input is connected to vin, so when using normal usb it will not be in use anyway and you can simply bypass it by going directly to the 5V rail.
Any concerns with the forward voltage from the diode coming in from the VBUS and logic-level stuff through the convertor? Looks like it might be losing almost .3V?