I got a few of these boards to test out on a small project, and I think I want to SMT mount them.
I can’t find a mechanical drawing of the bottom side of the board so I can design the proper cutouts in my PCB to allow for the bottom-side mounted components.
Are these available somewhere and I’ve just missed them?
-Chris The Stumbler
Sacheon, South Korea
I think if it was me, and I don’t mean this in a derogatory way etc, I’d just cut one big rectangular hole. The bottom side of that board is pretty jam packed with components from the looks of the product picture.
No offense taken. That’s basically what I plan to do. The question is how big a hole.
Also, are the schematics anywhere to be found? I’m trying to sort out power supply stuff.
All I’ve seen is the Pinout. I had a look at that to see if the PICO Lipo Shim would work with the Tiny 2040. Not going to work unfortunately. The Tiny has a different pinout from the full sized PICO. Power wise anyway.
Pimoroni don’t frequently supply schematics, unfortunately. You may have to resort to measuring it yourself. One big rectangular cutout for the components should be quite straightforward.
Also, are the schematics anywhere to be found? I’m trying to sort out power supply stuff.
What kind of power supply stuff? What I’m assuming is the regulator on the board is absolutely tiny, you’d probably need to ask them for the part number if you need to know the max current output etc…
Well, I wanted to optionally power the board externally if not using the USB connector. Is Vbus pin bidirectional? Could I power it with +5 volts on that pin? Can I power it in a +3.3V system by applying only 3.3V to the 3V3 pin? Yeah, also, max current available on 3.3 would be useful, as well as current consumption.
If what you say is true, that they don’t provide data sheets and drawings for their products, that’s sad. It removes them from consideration from a whole niche market. I could never recommend this to a client if that’s true.
There are schematics and links to data sheets for some items. That doesn’t help you but I thought it did bear mentioning.
I don’t know how much of this transfers to the Tiny 2040 but you can power a Pi PICO from a battery via the VSYS pin.
VBUS is the micro-USB input voltage, connected to micro-USB port pin 1. This is nominally 5V (or 0V if the USB is not
connected or not powered).
VSYS is the main system input voltage, which can vary in the allowed range 1.8V to 5.5V, and is used by the on-board
VSYS diode (D1) adds flexibility by allowing power ORing of different supplies into VSYS.
VSYS is the main system ‘input voltage’ and feeds the RT6150 buck-boost SMPS, which generates a fixed 3.3V output
for the RP2040 device and its IO (and can be used to power external circuitry). VSYS is R-C filtered and divided by 3 (by
R5, R6 and C3 in the Pico schematic) and can be monitored on ADC channel 3. This can be used for example as a crude
battery voltage monitor.
The buck-boost SMPS, as its name implies, can seamlessly switch from buck to boost mode, and therefore can
maintain an output voltage of 3.3V from a wide range of input voltages, ~1.8V to 5.5V, which allows a lot of flexibility in
the choice of power source
Raspberry Pi Pico Datasheet
Just checking back on this topic. Have the schematics been released yet for the Tiny2040?
-Chris
Awesome, thanks for releasing these!