Boron Solar Charging with 1.5.0-rc1

Hardware
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UPDATE for Device OS 2.0.0.rc-1 , Boron LTE

Using the same bench setup as the Original Post.
The LED Test Light Stand at the current configuration produces 119 mA @ 5.08V (606 mW) using the Voltaic 2W panel placed at a repeatable position. So 606 mW is the available Solar power for the tests below.

Using the USB Connector for Solar Input results in the following entering the 2aH Li-Po @ 3.95V:

Awake            116 mA     458 mW
Stop             122 mA     482 mW
EN Pin           122 mA     482 mW
Stop w/ Network  
Hibernate        123 mA     483 mW

That’s ~80% of the available panel power being stored into the Li-Po… not bad.
All modes maintained the Solar Panel at ~5.04 V, so DPM still works.

3 of the 4 modes handled the Cycling of the Solar Panel Output to simulate Clouds.
Hibernate Sleep will wake the Boron LTE when the Solar Panel Cycles (not good).
DPM also gets wonky after a Cloud wakes the Boron from Hibernate.

A side note: using Stop Sleep with Network Standby results in 10mA of sleep current (seems too high). If your external watchdog performs an EN Pin Shutdown during this, the PMIC will have problems with DPM. I realize that’s an edge-case.

I also tested a 6V DC Power Supply using the same API settings for comparison:

*6V PowerSupply  255 mA    1060 mW

Power Configuration settings used for all tests:

  conf.powerSourceMaxCurrent(900)
      .powerSourceMinVoltage(5080)
      .batteryChargeCurrent(1024)
      .batteryChargeVoltage(4208);
  System.setPowerConfiguration(conf);

Solar Charging through the USB connector w/ 2.0.0.rc-1 appears good so far, but there are still some quirks with this release that need investigation prior to official roll-out.

Particle only gets 1-shot at the initial LTS release.
I’d recommend more physical testing prior to leaving Release Candidate Status.
For the past 2 years, I’ve tried to get Gen3 hardware to pass Validation Testing (prior to a 2-week Trial) so I could use Gen3 in Industrial Environments.
I have high hopes for LTS 2.0.0, but it’s still not ready due to a lack of physical testing(IMHO).

I’m going to perform detailed testing for Stop Mode and EN Pin Shutdown, mainly to stress test the API and PMIC as a Li-Po nears the termination voltage under different operating conditions w/ DeviceOS 2.0.0.rc-1. I hope Particle will do the same :sunglasses:

I know that not everyone is concerned with Solar Recharging, but we’ve seen in the past that some of the issues discovered in Solar Tests also show up with a Boron on AC/DC power supply.

Cheers !

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