I have a LIPO 3.7V battery attached to the JST-PH 2p connector. If I measure the voltage straight on the MKR board where the connector is soldered to it, I read 3.9V. Yet, the board will not start. I don't think it has anything to do with the sketch (which runs fine when power is coming from the micro USB connection), because not even the green led will turn on. What could be the cause of this?
This is my schematic. But since it is running fine from USB, I doubt that has anything to do with it.
I tried without the OLED, it started one time. Then I loaded the blink example sketch, since my sketch also uses WiFi. I think that als uses some power.
With the blink sketch it will keep running on battery when I first start on USB and then remove the USB connection. But starting on battery will happen only occasionally. Also hen it will run on battery, the leds will dim somewhat.
Can ik be some resistance in the breadboard and/or wiring? Because I have the battery wiring running through an on/off switch.
Why did you highlight pin 27? The MKR boards have a special JST-PH 2p connector through which the board will also charge the battery when connected to USB.
Today I did an experiment. Instead of the LIPO battery I connected a Li-ion battery
(NCR18650B) to the JST-PH 2p connector whithout any wires going through the breadboard and switch. It started up fine, even with the OLED connected and working. Then I reconnected the LIPO battery without the wires going through the breadboard and switch. But again it didn't start.
The LIPO is 2000mAh, the Li-ion is 3400mAh. Could that difference be the cause? The MKR board recommendation is 1024mAh.
No
However the NCR18650B is an unprotected battery and the LiPo you are using is a protected battery.
I would think that the MKR should work both types, maybe not
Are you sure you have the correct polarity when you connect the LiPo battery?
Well if you connected the 18650 battery the right way, I would think you also connected the LiPo right.
As I said before, the only difference is protected and not protected.
Hopefully a MKRWIFI1010 expert will come along with an explanation.
Hobby batteries for flying/driving tend to be higher current (compared to a clock, for example). If the non-working battery was intended for a low-current device, could it be restricting the current flow, and does the MKR need more current?
I got out my unused, unopened MKR WIFI 1010. (I got it a week or so ago.)
I plugged a 3.7V LiPo into the battery socket and the factory-loaded sketch/program started running: the RGB blinks r,g,b and the built-in blinks too (at a different rate vs the RGB).
I was surprised to see, contrary to the FAQ, the Green power LED is on, too.
"VCC" = 3.3V
"VIN" = 0.59V
"5V" = 2.98V
Vbatt is 3.77V
Looks like the PCB is dated - "12/23"
@dippides -- inasmuch, nothing on the breadboard should be conn'd to 'VIN' or '5V' as appears you may have done.
