I remember it being something like 1-2A. Let me dig up the post.
Thanks @peekay123, for the details (figures) this does go with my PR for the docs.
As I asked @kennethlimcp in the PR comments, it would be good if the Spark team could fill in the gaps.
@kennethlimcp, you may be right! I looked at the BOM and it shows a 30V, 3A diode though I suspect this is not up to date. It may be correctly identified on the eagle files.
Letâs have the mystery solved by @will. 
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i think youâre right @peekay123, the only way i could connect and make my GPS powered on is through a separate power supplies with a common ground. this raises me another question, i am thinking, can the spark battery shield support a higher voltage than the 3.7V LiPo battery?
i think that when a 7V battery connected to the battery shield to power up the spark core, i may place a jumper wire directly in the battery shield to the GPS receiver to supply it with the needed 5V. am i correct and is this possible? 
NO. DO NOT connect a 7V battery to the charger.
The TPS61200 is a boost regulator, not a buck/boost so requires a lower input voltage than the output.
Also, the MCP73871 charger IC is only rated for a 3.7V battery with 4.2 as the charging voltage.
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but i really an external 5V source to power up my GPS, another thing is that iâm gonna make it portable so i really need batteries. 3.3V to power up the spark and 5V to power up my GPS. how can i power the GPS up?
also as per seeing the data sheet for the MCP73871 the Vin has a maximum of 7V so i thought of it is capable of having a power source 7V battery.
The MCP73871 can take in up to 7V for DC input to the charger but it cannot use a battery of 7V.
It donât matter what the MCP can take, the switching supply is boost so needs a lower voltage input that the output.
Why not look at the LiPorider Pro from Seeed Studio. It can provide up to 1A of current at 5V.
im in the philippines and its hard to find pieces which you guys have and im under time pressure to finish this project. so what do you think is other way of making a 5V like what @peekay123 said âor lager currents, the Core and user circuit should be powered in parallel or from separate power supplies (with common grounds)â
I donât understand whatâs going on here.
1.) Find a 5V supply and verify that the GPS module is working.
2.) Connect Vin on core ----> Vin of GPS
Connect GND on core --> GND of GPS
Done.
yeah i know about that, but the problem is that what portable power source is compatible to the spark and the GPS
Isnât that answered in the posts already?
You said you have a 3.7V battery so connect it to the Battery shield and plug the Battery shield to the Core. Next would be to power the GPS module via Vin and GND.
If you are pressing for time, why not just stick to the USB cable and demonstrate off a USB port?
It allows you to develop and even figure out your code instead of trying to solve something with your limited resources and going nowhere.
ive done it but to no luck, still wont power on.
My question to you will be:
okay will come back after iâve tried. gonna go to class first. thanks btw
On your other thread there is a reference to the GPS data and it shows 4.5 to 6.5V.
The core outputs 4.7V on VIN pin when you have power via the USB. A PC can supply 500mA which is more than enough to power your core and the GPS, Does this work? How are you testing this? Where are you locating the GPS antenna for these tests? It must have a good clear view of the sky and a window ledge should provide enough signal to test with.
Do you have code to read the NMEA output from the GPS on the RX pin?
The battery shield battery that comes with the board is a little on the weak side and could explain why it does not work for your testing. I have a 1400mA battery that I connected to it and this provides better current output from the supply. I suggest you find a bigger 3.7V LiPo battery.
yea i think i just figured out one reason why this does not work because im testing it inside my house which is surrounded by buildings. i may find a open place tomorrow to have a clear connection with the 11 satellites.
yup i already have a code which is the TinyGPS library which as youâve said reads NMEA strings from the RX and TX of the GPS.
the 3.7 battery i have is the one from the maker kit. it only has 450mAh.
I thought, I have pointed this out as a possible reason twice before!
and a third time from v8dave
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