I have successfully programmed two Thing Plus RP2350 modules using the Arduino IDE connected via USB. Each RP2350 board has an external BME temp/humidity module connected via Qwiic. The programs on both RP2350 boards were tested and executed normally when connected to USB. When I started remote testing, the USB was disconnected and a fully charged LiPo battery (3.77 volts) was connected to the RP2350 boards. The programs on both RP2350 modules failed to start and there was no indication that power was being delivered to the external BME modules. I confirmed that the LiPo battery was OK (i.e. valid connector polarity, etc) by connecting it to a FeatherS3 board. When the RP2350 boards were re-connected to USB power, the programs again executed normally. However, I noticed that an IC mounted on the bottom of one of the boards directly below the battery connector started to get very hot, so I disconnected the RP2350 immediately.
…go look at the markings on the battery connectors again.
You’re powering it backwards. Also just FYI 4.2v is the fully-charged capacity of a standard lipo
Yes, 4.2v is the fully charged capacity of a LiPo, but 3.7v is a nominal and acceptable level. When I connect a “standard” LiPo battery to a “standard/keyed” battery board connector, I assume that the board connector is using the polarity as shown on the FeatherS3 board (and every other board that I’ve worked with). Has Sparkfun chosen to reverse the connector polarity on all of their boards?
This is unfortunately a long-term consistency problem in the industry:
The connector has become a common “standard”, but the polarity has not been standardized. This was before my time here, but I’m guessing that when we started putting battery connectors on our boards, we just had to pick one.
All of the Sparkfun boards that I have found on the Sparkfun website have the same polarity configuration that is shown on the FeatherS3 pinout diagram. The Thing Plus RP2350 board appears to be the ONLY one with reversed polarity (i.e, with the positive connection on the right side).
Oh crap…
Ok, thanks for reporting this, guess we’ll need to do a revision!
Please work with @TS-Russell to resolve this however is best for you, that’s our bad for getting the polarity flipped.
FYI for transparency - we’ve got a v11 revision on order that fixes the polarity to match the rest of our products. It’ll take at least a few weeks for production. In the meantime, we’re adding warnings to our docs and product page that v10 has the wrong polarity, and pulled our stock off the product page. We’ll reach out to customers who’ve purchase the board to warn them about the flipped polarity.
Dryw,
Thanks for the follow up! I’m looking forward to receiving the v11 replacement boards so that I can move forward with my project.
Tom Sanders