P2 Battery Board

I am planning to make some P2 board following the tutorial, is there a reference design for a battery board yet that is available (LiPo charger, Power selection logic, etc.) i.e. similar to the Photon2 that could be recommended please?

There is no public version of the Photon 2 design, however the Argon charger design is a good reference for a simple charger that does not use a full PMIC and fuel gauge.

@rickkas7 Thank you for the pointer. Your answer suggests that the Photon2 design unlike previous Generation boards will not be open source?

There was a mention of a battery board in the tutorial about the P2 initial board design, is that now not going to be developed or released as a tutorial?

I was going to make a battery-based P2 design based on the B Series SoM base board sample design (bq24195 + MAX17043), however the P2 version of Device OS does not include PMIC and fuel gauge features, so those would need to be implemented in user firmware instead. Also, the RTL872x is not a particularly low-power device and isn’t ideal for powering by a small LiPo. It’s not possible to keep the Wi-Fi connection up while in sleep mode.

The power supply for the P2 module is simple (500 mA at 3.3V), and various regulators and chargers are still sometimes difficult to obtain, so it’s best to just find a reference design using chips that you are able to source.

The Photon 2 will be a closed source design. This is the case for all production modules (B Series SoM, Tracker SoM, E Series) but will also be the case for the Photon 2.


@rickkas7 As ever, thank you for your comprehensive answers. I’m not aiming at fully powering the P2 from a LiPo battery, this is just backup power to enable a mains AC powered device to send an event that AC power is lost and shutdown/hibernate. I need to look at the power consumption of the P2 when sleeping - this is an issue for some of our devices (think big LiFePo batteries). Can any devices keep a WiFi connection up whilst sleeping? The Torex ICs in the Argon design appear to be available and not EoL. Thanks again.


This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.