Pico Prototyping - Building a "Pico Uno"

Posted by: @byron

Posted by: @zander

Do maker clubs not do a similar thing still,

I've no experience of maker clubs, but I doubt if they actually make there own pcb's any more as they would in times past.  As you say it just so easy and cheap these days to do your own design in a suitable pcb cad program.  The one I use, easyEDA, does not take long to get to a level where simple pcbs can be drawn up and once the design is complete then just a click will send it off to the pcb maker (along with a credit card deduction)

@byron It would be really convenient if CirKit could also create a PCB design from the input.

Posted by: @frogandtoad

Posted by: @zander

@frogandtoad I have been looking for a project for my Pico's, this looks like a start

Go for it... am sure @byron can lead you in the right direction

@frogandtoad Perhaps

Posted by: @byron

Posted by: @zander

Are there any reasonably priced places in NA or are they all in China?

The ones I have used have used have all been in China.  But then I live in the UK, so USA ones would probably be pricy for me.

@byron Probably so.

Posted by: @zander

@frogandtoad I know even less about this, would a sub-forum be a good idea? Then maybe a thread per board?

NO!

Posted by: @frogandtoad

Posted by: @zander

@frogandtoad I know even less about this, would a sub-forum be a good idea? Then maybe a thread per board?

NO!

@frogandtoad Ok, we know your view, but I will still propose it to see what the majority say.

@dronebot-workshop Hey Bill, great article and project! I'm kind of the reverse of some here: I liked the idea of a "breakout board" so much I gathered the parts even before my Picos arrived. Haven't done any real experimenting, yet, but really enjoyed building the project. Thanks!

I liked Bill's article so much that I designed and bought some PCBs. Attached are a couple of pix. However, I am having some power trouble that prompts me to ask what voltage did Bill set the output of the Mini-360 buck converters to? Thanks

@tracecom Once again I am confused. Where is the Arduino in this setup? Is that board in the picture what you mean by 'designed and bought'? How is that done and what is cost, it can't be cheap if a one of and so professional looking. As far as Bill's voltage, I would check the accompanying blog or try asking him. If I were to guess however it would be 3.3V.

@zander

There is no Arduino; the green board is a RPi Pico, the white board is my design, and the small blue one is an off-the-shelf AMS1117-5 Chinese module that I had in stock and used instead of the Mini-360 that Bill used. I used DipTrace to design the white PCB and ordered the boards from China. I wanted them in a hurry, so I paid for DHL shipping which ran the price up from $5 to $30 for 10 pcbs. When the PCB's got here a couple of days ago, I gathered the components and built up 2 boards for testing. My test results are mixed good and bad; the good is that my PCB layout is mostly okay, but the bad news is that I keep smoking regulator boards. I think the problem may be that the inrush current when the Pico starts up can exceed the capabilities of the AMS1117, but I am not sure yet. Hence, my question to Bill.

P.S. I don't know how to ask Bill directly.

@tracecom OH! Since the topic is 'Pico UNO' I thought this was a combined Pico and UNO project. I just had a look at the video and see it is not. That will teach me to stop reading the click bait and check the meat of the article/vid.

I bought a couple of the prototyping boards that Bill used somewhere, probably the same video. I am an old tube guy, so PCB is a totally foreign concept. I did try to learn some of them fancy cad / design a board things but my 50+ yrs of software experience refuses to learn any new stuff.

 I see the 1117 is a voltage regulator while the Mini-360 is a buck converter, might that make a difference?

@zander I wish I could have some of your software expertise; I write some code, but it's clumsy. My concept is that "voltage regulator" is a broad term that includes buck converters, and that the Mini-360 and the AMS1117 are both used to reduce an input of 12 or so volts to a voltage that the Pico can deal with (1.8 to 5.5V) at the VSys input. The AMS1117 that I used was the 5V version because that's what I guessed Bill had the Mini-360 set to, but I could be wrong. How do I ask him directly?

Posted by: @tracecom

I liked Bill's article so much that I designed and bought some PCBs. Attached are a couple of pix. However, I am having some power trouble that prompts me to ask what voltage did Bill set the output of the Mini-360 buck converters to?  

If you're building the third version, in the video at time 29:00 he says "about 5 volts".

@will Thanks. I watched that section again, and you are correct.

@tracecom I just checked the video and he says 'about 5 volts'. I would go with 5.5V which is the max that VSYS can take and ensures a solid 5V at VBUS in case you are using that to power other 5V devices.

Linear Voltage Regulators work much differently than BUCK converters. Maybe take a peak at Bill's video on that subject at

Asking the question on the thread associated with the video is one way, the other is the usual message method.

@zander Thanks. You are correct. Now I need to do some testing on the AMS1117 and see how much surge current it will tolerate.

P.S. I have some Mini-360 boards that will arrive Monday, and I could just use them, but I would probably need to change the PCB layout.