Hi, does anyone know which brand and type or 3.3v Voltage regulator is used on the Sodaq One? I would like to take a look at the datasheet, to find out if it will shutdown to prevent deep decharging of the li ion battery. Thanks!
Have a look at the schematic:
Yes, I had seen the schematic, but the 3V3 Regulation and switching section only shows a square with 5pins for the regulator. The type number is missing. So the schematic is not complete and does not help.
Based on the markings I believe it is the XC6220 (the same as on the Autonomo).
Specifically, the first 3 marking digits represent the variant type H63 with the last two digits the batch number.
See page 30: http://www.torexsemi.com/products/voltage_regulators/data/XC6220.pdf
Thanks Gabriel! It is good to have the datasheet. I see now that regulator will not shutdown if the input voltage is too low. Under these circumstances, it will try to keep the output voltage as high as possible. So that means I have to implement a bit of software to measure the voltage and if it is too low, shut down the regulator, to keep the current as low as possible. Thanks again for your help!
Good to know. Thanks for looking into this @EelkeVisser . Without protection it is quite easy to break a LiPo. I was actually expecting that a smart device such as this one also has smart software… /edit I suppose it depends on the type of battery used so it does make sense to leave it to the software or a small circuit on the battery itself.
As a follow-up question: Is it safe to use a LiPo instead of a Li Ion battery?
Hi Paul, I did not check the software yet, but I have read that you need to add a line of code to set an output pin to control the regulator. So I assume that the software doesn’t include a shutdown function. I need to investigate the software more on this to be sure.
The board should work also with a Lipo. I quote the website: “It has a solar charge controller and runs on a LiPo or permanent battery.” However I’m using an old li ion battery of an HTC Sensation mobile phone. The charge controller should charge with a maximum of 500mA and is limited to 4.2V. If the power source is powerful enough. I haven’t charged the battery yet, need to try this also!
Eelke I bit the bullet an hour a go and connected a LiPo. No puffs of smoke and it is sending packets. I must go somewhere so next I will connect it to my 5v car outlet to see if it charges.
So far so good.
When the SodaqONE is running on battery you have to keep the ENABLE_PIN_IO pin HIGH, otherwise the regulator (and so the board) will shutdown.
Yes, the board is designed to work with LiPo batteries. The charging is controlled by an MC73831.
The LiPo batteries will have an internal controller which will shut off when the voltage drops below a prespecified threshold.