Hey guys! I'm trying to make a quadcopter, and I'm running into an issue I don't quite understand. I am using MOFSETs to power the motors from a 3.7v lipo battery, and the arduino is connected to another 3.7v lipo battery. I used resistors in a previous iteration, but left them out this time to try for more power. I have since discovered that the resistors are important long-term, but I do not see how they could be causing the issue. The issue is this: The motors will spin as long as the arduino is plugged into my computer, but not when it is powered from the lipo battery. I tried to power it with a 9v, and it worked. (the motors are still powered from a separate 3.7v lipo battery). This would make it seem as though the board needs more voltage to function, but it will run the blink sketch and even work with an accelerometer while being powered by the lipo battery. I haven't included any diagrams or images because this is more of a conceptual issue I'm struggling with. I really don't get how the nano will work fine with everything BUT pwm when powered with 3.7v. Thanks for reading all of this, lmk if you need any more info.
Which one? Power connected to what pin?
Where????????????????????
What is powered from the lipo? The controller? On what pin?
A PP3? Bad idea. Too little capacity.
Do You get the message that schematics are needed? The Shakespeare type is not clear enough.
I see a potentially A big problem but without the SCHEMATIC which is not a frizzy picture I cannot explain it to you or ask for the information I need to answer your question. I assume you made a drawing and did not just connect wires. Also while you are at it, add links to technical information on all the hardware parts, links to azon, alie, and others like that are sales info not technical info. I would suggest you go through this forum and look for applications that fail because of 9V batteries.
Most MOSFETs need about 10V or more (gate to source) to fully turn-on and saturate.
A "logic level" MOSFET can be controlled with 5V but depending on the particular part 3.7V might be "pushing it"
Hi,
Sorry but had to spread it out in point form, looks easier to read.
I haven't included any diagrams or images because this is more of a conceptual issue I'm struggling with.
If you have built it and are having this problem, it is not conceptual.
Do you have a DMM?
PLEASE: Can you please post a circuit diagram of your project, including power supplies, use a pen(cil) and paper and post an image of your project would be fine.
Please do not use a Fritzy picture
Your description of the problem shouts that it is a power supply problem, not conceptually, but in real life.
Thanks.. Tom... 
Hi,
Is this thread related to this;
Tom...
A part number would be helpful. Better yet, a datasheet. NOT ALL MOSFETS ARE THE SAME.
The thing I see is many of the users do not want to draw schematics yet a large portion of there problems are in the connections, power etc. It appears they spend about a week or so with lots of questions and then maybe, give up, and some get lucky. It is amazing how many problems you find when doing a real labeled schematic including Technical links. That schematic makes them look like a pro. It appears to me that most of the time when a proper schematic is posted the solution is usually within day or so. Good schematic capture software can be gotten for the downloading. Months later a wire comes off, looking at the schematic and putting it back saves lots of headaches.
It's too much bother, why can't the computer do it for me? 
Right on, to bad they do not understand what they are missing and failing to learn. Schematic is the language of electronics.
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