Page 1 of 1

Plain Pico D4

Posted: Sun Aug 25, 2019 10:04 am
by DJBxxx
Hey all,

I am interested in tinkering a bit with the Pico. Did I understand everything correctly: I can just solder the pico to a breakout board (like the one below) and upload code with an ftdi? Is that really all I need? I know I won't have wifi or bluetooth but still good fun. It sounds too good to be true :D I know the Pico is a SiP and the datasheet says that it includes all peripherals. Also I have seen many minimalistic projects but not this explicit one. All of them had at least an antenna and one or two passives. So I figured I'd rather ask here before getting into it.


Cheers
Screenshot 2019-08-25 at 11.35.36.png
Screenshot 2019-08-25 at 11.35.36.png (754.81 KiB) Viewed 3258 times

Re: Plain Pico D4

Posted: Mon Aug 26, 2019 1:17 am
by ESP_Angus
Hi DJB,

This will quite possibly work. There are some reasons it may not work reliably:
  • The PICO-D4 does still require some external components, notably power supply capacitors (see Section 7 "Peripheral Schematics" in the datasheet). You might need to find a way to solder ceramic caps directly to the breakout board, to keep the overall series resistance & inductance as low as possible.
  • The antenna connection needs to reliably send and receive 2.4GHz so usually it's an controlled impedance feedline. The breakout just has a regular PCB trace connected to the antenna pin. But if you can solder an external 2.4GHz antenna then it might work well enough for a very strong Wi-Fi signal, anyhow...? There is some small risk of damage to the RF amplifier due to the (likely) large impedance mismatch.
Overall soldering a couple of capacitors and some wires directly to a WROOM or WROVER module breakout board will probably be more reliable and not that much larger (although these breakouts can also be unreliable as most of them don't have enough capacitors on the breakout.)

If you decide to have a try with the QFN breakout, please post your results!

Re: Plain Pico D4

Posted: Mon Aug 26, 2019 3:41 pm
by DJBxxx
Hi ESP_Angus!

Thank you for the reply! So taking that into consideration I will give it a shot and let you know what my results will be :)