Question about Charge and Play Circuit

[sl33pydog]

Hi Everyone,

My first post was "PM Sent" so hopefully this one will be better than that. I come from the world of diy drones so I know a little bit of lipos, voltage regulators, etc. But this is a whole new world I would like to try. Looks like fun.

I have a question in regards to a Lipo play and charge circuit. I have an almost fully functioning portable on the way courtesy of kinect360 and I was looking into a single power plug when the system is off to play and charge the system. I haven't seen kinect360's circuit but this one might be for the next one once I get my feet wet finishing the one from kinect360. This picture in part came from shockslayer's play and charge circuit so credit goes to Life of Brian for the battery drawing, skyone-regulator, beta-N64, Kyo-Screen, Scythe-fan and shockslayer for putting that post together.

There is an option depending on if the lipo charger won't turn off once it's powered to put in a switch up at "Option A" to turn off the charger. There are lights to indicate when the battery is full.

The charger is from Adafruit: USB/DC Lithium Polymer battery charger 5-12V - 3.7/4.2v cells

but they do mention doing multiple cells and maybe it has to do with putting the circuit in front like in the picture. I'm not too sure. I haven't read up on the chip they use.

Please tell me your thoughts. I would like to try it but maybe someone here has already thought of this.

Potential Battery Supply Charge and Play.jpg

(127.52 KiB) Not downloaded yet

[Carb0]

The adafruit charger only works with one cell. You need to replace the chip that handles the charging to make it work with two cells:
http://forums.adafruit.com/viewtopic.php?f=19&t=34399

Maybe this is the better option:
http://www.batteryspace.com/Internal-Sm ... ttery.aspx

The circuit looks fine to me but I think someone with more experience should confirm that.

[sl33pydog]

The adafruit charger only works with one cell. You need to replace the chip that handles the charging to make it work with two cells:
http://forums.adafruit.com/viewtopic.php?f=19&t=34399

Maybe this is the better option:
http://www.batteryspace.com/Internal-Sm ... ttery.aspx

The circuit looks fine to me but I think someone with more experience should confirm that.

Yah I got a little confused with the silkscreen they had on there with calling out both voltages. That forum post makes sense now.

I really like the batteryspace module you sent. Is that what most people use? Also what kind of wire diagram would you do with this?

I was also thinking of this one too: http://www.digikey.com/product-detail/e ... ND/2170219
I'm not sure if you are able to play and charge like on a phone with this kind of setup.

[sl33pydog]

whoops wrong chip. It's the dual cell version:
http://www.digikey.com/product-search/e ... vendor=150

[Mooper]

I've been looking for a single power port solution as well. I've come across the BQ24170 IC from ti. It looks like it has all the features needed. Unfornuetly I have zero expierence in designing custom circuit boards. But if one of our more technically inclined members could design a board to utilize it, i believe it would be a good solution.

Here's the data sheet
http://www.ti.com/lit/ds/symlink/bq24170.pdf

[Carb0]

Yah I got a little confused with the silkscreen they had on there with calling out both voltages. That forum post makes sense now.

I really like the batteryspace module you sent. Is that what most people use? Also what kind of wire diagram would you do with this?

I was also thinking of this one too: http://www.digikey.com/product-detail/e ... ND/2170219
I'm not sure if you are able to play and charge like on a phone with this kind of setup.

Most people use two different power jacks, one for charging the battery (with a smart charger) and one for playing from the power supply (here you can use a normal 12V power supply). The advantage is that it's cheap, easy to build, and safe (i.e. you can't accidentally charge the battery with the normal power supply). With the module I sent you you could use the same power supply for both power jacks since the smart charger would be inside the portable. Maybe you could also use only one power jack if you use a switch, but you won't be able to play and charge (the Adafruit charger also doesn't play and charge btw, the description is very misleading).

The only thing I know that allows you to safely play and charge your portable is the following:
http://www.batteryspace.com/CMB-for-11. ... -char.aspx

Unfortunately, it only works with a 11.1V battery pack. A GC portable would also run on 11.1V but you'll need more space inside the portable for batteries.

Maybe you can post your question also on modretro.com. There are more people that have experience with powering portables.

I've been looking for a single power port solution as well. I've come across the BQ24170 IC from ti. It looks like it has all the features needed. Unfornuetly I have zero expierence in designing custom circuit boards. But if one of our more technically inclined members could design a board to utilize it, i believe it would be a good solution.

Here's the data sheet
http://www.ti.com/lit/ds/symlink/bq24170.pdf

Yes, that looks like it could be what is needed for such a circuit. Unfortunately, I also don't have enough experience to design it.

[sl33pydog]

Anyway to use one of the eval boards those chips accompany? like the:

http://www.digikey.com/product-detail/e ... ND/2696193

even though that's 100 dollars.

or the:
http://www.digikey.com/product-detail/e ... -ND/679855

Which is around 50.

I can't tell though where the system power would come from unless I'm missing the point to these boards. Are you supposed to just pull from VCC and when plugged in the voltage won't add onto the Batt voltage?