Hello Particle Community,
I have been enjoying the products that Spark / Particle has made, unfortunately all of my devices ( Currently 3 SparkCores and 1 Photon [ Now ] ) have ened up frying one way or the other. Most of the time due to Voltage Regulation issues on the sparkcore with and without external regulation added as a precaution. Anywho, Sparkcores aside and there issues, this Friday I received the Photon and wanted to document what happened to mine.
Before I did anything with it I went and read Photon’s Documentation ( Link Below )
Please Note that I did not see any Min Voltage for VIN
Powered the photon with a Li-Ion Cell, ( Li-Ion 4v1 Max to 3v3 Min ), Thinking it will work just Fine. Powered the Photon for a full Day without issue coding to track solar data. I had it reading and sending voltage and battery percentage over the web just fine, Until the last update i got early in the morning stating that the battery was at 15% left. Refreshed the Page to see if it would update, never responded, the rest went down hill after that.
Last Publish that was sent to me was 15% Battery ~3v42 ( Calculation below )
So, Power Your Photon with 3v5 or Higher, Yes the Photon has a MIN VOLTAGE IN RATING
Photon Use Note : Voltage Read From Resistor Divided Circuit & Li-Ion Max and Min Voltage.
PercentageofBatteryLeft = (VoltageRead - Voltage_min) / (Voltage_max - Voltage_min) * 100
PercentageofBatteryLeft = (3.42 - 3.3) / (4.1 - 3.3) * 100
PercentageofBatteryLeft = (0.12) / (0.8) * 100
PercentageofBatteryLeft = (0.15) * 100
PercentageofBatteryLeft = 15 %
I Hope this helps with others projects!
Power Resources / Links :
Gathered From Above Links (Page 4 in the PDF and Right on the Digikey Page) :
2v5 = Absolute Min Voltage
3v5 = Absolute Min Voltage when 3v3 Fixed Regulating (“VIN = 3.5 to 5.5V, VOUT = 3.3V 0A < IOUT < 600mA”)
Let the Documentation Reflect a 3v5 VIN Min value rather than blank for other Users.
Have a Great Day.