Charging behavior for Maple and Maple Native

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Charging behavior for Maple and Maple Native

(8 posts) (4 voices)

Started 3 years ago by gp
Latest reply from mbolivar

gp
Member

Ok, so I have both a 1x Maple Rev5 and a Maple Native.

I bought an external battery pack, and then put a jumper across the CHRG selector on the PWRSEL header and across the USB on both boards per the documentation.

I can fully charge the external battery pack with both the Maple and the Maple Native, after a handful of minutes the charging indicator goes to green.

So here is my question. How does this help me for a self contained design if I have to change the jumpers after the battery is fully charged? In an ideal world, I should be able to connect a battery pack to the Maple, plug a USB cable into the Maple, and then have it charge the battery pack and run the Maple from the battery pack or the USB power connection.

Am I missing something here? What would it take for the Maple or Maple Native to be self contained with a LiPo battery pack, and powered from the USB connector and/or internal LiPo battery, and with the battery pack charged any time the Maple is attached via USB?

Thanks in advance,

GP

Posted 3 years ago #
gp
Member

Bueller... bueller... anyone here?

Surely someone is using the Maple or Maple Native with a battery pack that can be charged without having to switch a jumper back and forth after each charge...? What is the point of an integrated charging circuit if you have to select which power source is being used to power the board?

Posted 3 years ago #
robodude666
Member

gp,

It's designed primarily as just a built-in charger, and not really a power source.

The Maple does not have an auto-switching circuit like the Arduino does. It kinda sucks that it doesn't, but at the same time it's fine. You don't switch between EXT and USB all that often, so it doesn't matter.

With the charger, it's just that really: a built-in charger. You can use a battery, and charge it, so you don't have to buy an extra $30 LiPo charger PCB. It's something that can be improved on for the Maple II, certainly.

If you are doing this frequently, you can get a double triple throw switch. Use one switch to switch the common lead between USB/BAT, and the second one to turn on/off the charger. This way you have one switch which will: Turn on charging when USB is enabled, and turn off charging when BAT is enabled. Solder the leads to some female headers, and you have a nice switch you can mount to your enclosure for a project.

-robodude666

Posted 3 years ago #
gp
Member

So is this on the roadmap for the Maple II?

And do the owners of Leaf Labs actually read this forum at all? Their lack of participation in supporting the Maple line of products doesn't bode well for the long term viability of this hardware platform.

My .02

Posted 3 years ago #
crenn
Moderator

The current Maple II design implements an IC which will do USB/external power charging with the LiPo and automatic switching.

This is the IC they're using: http://www.linear.com/product/ltc3566

The only thing you'll need to select is power from USB or from external power according to this:

The user must select either the USB input or an external power input, but not both, this chip does not have an internal power path manager

The owners do check this forum, just usually the moderators and users will answer before hand. I saw your post previously but forgot to reply (had my neck seize yesterday which threw out my plans for the day) and I apologise about that.

As for your query about automatic switching. It might be possible to automatically do it with a simple board to plug into the header, however I'm not 100% how to implement it (I need to grab components as I have a different project which needs that capability) safely to prevent leakage into the battery. Essentially I'm looking at using mosfets to do the switch automatically.

Posted 3 years ago #
gp
Member

Ok cool, glad to hear that. Sorry to hear about your neck.

So is it safe to assume that any development we do on the Maple or Maple Native should be relatively easy to port over to the Maple II?

And will the same reference designs be available for the Maple II if we wanted to create a custom design based on that platform?

Does Leaf Labs provide any type of custom EDA services for that purpose?

Last but not least, what is the ETA for the first Maple II rev?

Thanks in advance

Posted 3 years ago #
crenn
Moderator

Eh, it's only my neck! I'll be fine, it's a little sore still but I'll be alright (hopefully in time for my last exam on Thursday).

As the chips are near identical between the STM32F1 series and STM32F2/4 series. There are slight differences but development for the Maple/Native should be relatively easy to port over or if everything goes well, will just work on the new Maple.

There is currently a schematic for the Maple II design on github available from here: https://github.com/leaflabs/Maple-II

I'm not sure what you mean about custom EDA services, I'll leave that for them to answer.

Last I heard, the Maple II is currently being prototyped still, so I can't say when it will be released. I'm hoping it will be in the next few months, but it will be a case of leaflabs will announce when it's ready.

Posted 3 years ago #
mbolivar
LeafLabs

yeah, so, maple ii.

turns out the F4 BGA parts are expensive. too expensive, you might say (we do say).

there's been an entire comedy of errors going on here at leaflabs. the upshot is we redid the board design while plowing ahead with the software on the F2 boards we had at hand. a blog post will explain the situation this week.

Edit: more detailed answers to gp's questions.

So is it safe to assume that any development we do on the Maple or Maple Native should be relatively easy to port over to the Maple II?

That depends. Code based on wirish (the high-level Wiring/Arduino-like APIs) will work as-is or be trivial to port. Code that relies on the C APIs in libmaple proper will continue to work as-is on STM32F1 (per our policy of "no intentional backwards-incompatible changes without a deprecation period of at least one release"), but many of the interfaces have been generalized to make it easier/possible to write code that works on F1, F2, and F4, with some attendant deprecations. As I said, the details are forthcoming, but check out the development branch if you're curious:

http://github.com/leaflabs/libmaple/wip-family-support

This branch will be merged into master prior to the next release.

And will the same reference designs be available for the Maple II if we wanted to create a custom design based on that platform?

Yes, we're releasing the design files under the same sort of open licenses we always have.

Does Leaf Labs provide any type of custom EDA services for that purpose?

We do. Contact us at info@leaflabs.com if you're interested in custom work.

Posted 3 years ago #

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