tl;dr - Is there a relatively simple way to power an arduino mini or nano with a Li-ion battery and recharge it with a mini-USB connection?
What I want to accomplish is pretty easy - just send a character from one arduino to another when a button is pressed, over the air. They must also be battery powered. At this point, I'm trying to reduce the size and the cost. The Arduino Fio seems like the perfect solution, but I would like the whole thing to be smaller and cheaper. I would much rather use a RF module,which is smaller and costs 5$, as opposed to the 22$ Xbees. If I was to use this instead, the whole Xbee socket on the Fio seems like a lot of wasted space. Also, you need some sort of extra chip to program it directly. Ideally, I want to accomplish what the Fio has done with the built in battery charger but with a Mini or Nano. Can this be done easily? safely?
Thanks, this seems perfect! Im fairly new to arduino, and completely new to using rechargable batteries in my projects. Are there any tutorials available for this, or is it just a simple plug in and play? I was thinking of using an arduino mini (since it doesnt have a built in USB connection), connecting the TX and RX to a female mini-USB, and then connecting this IC to the power and ground of the usb, so that I could charge the battery and upload sketches. Is this how it would be done?
There are two ways you can upload new sketches to the Arduino Fio: you can use an FTDI USB-to-serial cable, or USB-to-serial adaptor board; or you can program it wirelessly, over a pair of XBee radios.
Take look at edge of PCB, It is guaranty no QA for production. But it is sold dirty cheap at Shenzhen market. I guess "you get what you pay for"
This will convert 3.7 v li battery to 7.5 v, feed it to Vin of nano. nano has auto sensor circuit will power by Vin even we connect usb port to pc (5.0 v) for uploading sketches.
Ok, but how do I charge the battery if I use this? I need a separate USB connection right?
Edit: So it looks like the the Fio is the only model that is 3.3V? So every single cell Li-ion battery on sparkfun would only be compatible with the fio i guess? I know exactly how to use the Fio to accomplish this, but Im looking for a better solution. My main issue is what is the most simple way to power an 5V Arduino (nano, mini etc) with any of the small Li-Ion batteries that Sparkfun sells. I need to power it and also use a usb to recharge it
This would be amazing, since it would bring down the cost to about 25$ per unit as opposed to 55+$ when using the Fio
The next thing it wiring these components together, as I have no idea how to use the IC. My knowledge of circuitry is pretty much what I have learned from doing failry simple arduino projects.
Then how does the Fio do it, since it is also 3.3V? Isnt that what the IC does, protecting the arduino from voltages that are too high/low? What else would you recommend?
How about this? It outputs a constant 3.3V or 5V and also has charging built in: https://www.sparkfun.com/products/11231
All of these converters are pretty expensive though
aGont:
Then how does the Fio do it, since it is also 3.3V? Isnt that what the IC does, protecting the arduino from voltages that are too high/low? What else would you recommend?
The Arduino Fio can be powered with an FTDI cable or breakout board connected to its six pin headers (as marked on the bottom side), or with a regulated 3.3V supply on the 3V3 pin or a Lithium Polymer battery on the BAT pins.
sonnyyu:
At start battery voltage is as high as 4.2 v , and too high to feed to 3.3 v Arduino.
Sorry to keep reposting, but I keep finding new information. Sorry sonnyyu, but it looks like youre wrong:
[quote author=Tom Carpenter link=topic=168050.msg1251073#msg1251073 date=1369350606]
Ignore me, I looked up the part and the datasheet says it operates over the range of 3.2V to 4.8V, so you would be fine conecting the LiPo directly to it. In fact according to the datasheet, it is DESIGNED for use with a 3.7V LiPo battery.
If this is true, does that mean I can use a basic LiPo charger without any step-down converters?
[/quote]
datasheet says it operates over the range of 3.2V to 4.8V might means GPS module, not Arduino.
Arduino Pro Mini
Summary
Microcontroller ATmega168
Operating Voltage 3.3V or 5V (depending on model)
Input Voltage 3.35 -12 V (3.3V model) or 5 - 12 V (5V model)
Great! So essentially the only thing I need is a charger, and the following 2 do pretty much the same thing?
For 5$, I think I'll save myself some trouble and get the version that has the ports built in.
Anything else I need to know? Or do I just plug in the battery to the charger and the charger to the arduino? I really dont want an explosion of any kind