Gemma MO with integrated with Soft Button and LiPo Charger
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- HighlandRanger
- Posts: 18
- Joined: Wed Oct 30, 2019 4:22 pm
Gemma MO with integrated with Soft Button and LiPo Charger
I would like some advice. Is it possible to integrate a LiPo battery charger into a circuit with the Gemma MO so that I can just connect a USB to my device to charge without removing the battery? I would also like to add a soft button to switch it off, and possible a second button to switch between two flash patterns on the Gemma. Thanks!
- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
You can use a LiPo Backpack (https://www.adafruit.com/product/2124) getting 5v from a USB connection (e.g. https://www.adafruit.com/product/1833 or https://www.adafruit.com/product/4090). That'll give you in-place charging.
I did that with a CircuitPlayground Classic to make a coffee/tea timer. For on/off I used a TPL5110 (https://www.adafruit.com/product/3435): push the TPLs button to turn it on (then use one of the CPC's buttons to select time) and it will turn itself off when it's done (or a time hasn't been selected within a few seconds).
As for selecting lighting effects, that's a completely different issue.
Dave
I did that with a CircuitPlayground Classic to make a coffee/tea timer. For on/off I used a TPL5110 (https://www.adafruit.com/product/3435): push the TPLs button to turn it on (then use one of the CPC's buttons to select time) and it will turn itself off when it's done (or a time hasn't been selected within a few seconds).
As for selecting lighting effects, that's a completely different issue.
Dave
- HighlandRanger
- Posts: 18
- Joined: Wed Oct 30, 2019 4:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Is there a guide anywhere for how to attach the backpack to the Gemma?
- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Not specifically that I'm aware of. But... 5v and G (ground) to the USB breakout and BAT and G to the Gemma battery connector using a JST 2-pin cable (https://www.adafruit.com/product/261). Be careful of the polarity. Don't be tempted to use Vout on the Gemma to pick up 5v when USB is connected, it's indirectly (through a diode) connected to the battery input so weird stuff will likely happen when USB isn't connected.
Dave
Dave
- HighlandRanger
- Posts: 18
- Joined: Wed Oct 30, 2019 4:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Is there a wiring diagram? I'm not understanding very well. I'm sorry.
- HighlandRanger
- Posts: 18
- Joined: Wed Oct 30, 2019 4:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Would it be better if I use the Trinket MO?
- HighlandRanger
- Posts: 18
- Joined: Wed Oct 30, 2019 4:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
HEre's what I came up with. Does this look acurate?
- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
There you go. That should do it.
If you use an ItsyBitsy instead you can mount the backpack directly onto the ItsyBitsy, as shown with with the trinketPro on https://learn.adafruit.com/adafruit-pro ... n-backpack.
Dave
If you use an ItsyBitsy instead you can mount the backpack directly onto the ItsyBitsy, as shown with with the trinketPro on https://learn.adafruit.com/adafruit-pro ... n-backpack.
Dave
- HighlandRanger
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- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
There are several ItsyBitsy models; I'd stick with at least the M0 https://www.adafruit.com/product/3727 if you're using C++/Arduino, or the RP2040 https://www.adafruit.com/product/4888 if you want to use CircuitPython.
Dave
Dave
- HighlandRanger
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- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Except that the ground from the rings and button should connect to G (same as the backpack) not Vhi.
Dave
Dave
- HighlandRanger
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- Joined: Wed Oct 30, 2019 4:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Ah, nice catch, thanks. I guess that pin changed from the other iterations of the board.
- dastels
- Posts: 15820
- Joined: Tue Oct 20, 2015 3:22 pm
Re: Gemma MO with integrated with Soft Button and LiPo Charger
Looks good!
I don't know your physical constraints, but a 150mAh LiPo is pretty small for driving Neopixels. If a larger battery will fit, consider it. Or at least be prepared to if the 150 doesn't last long enough between charges.
Dave
I don't know your physical constraints, but a 150mAh LiPo is pretty small for driving Neopixels. If a larger battery will fit, consider it. Or at least be prepared to if the 150 doesn't last long enough between charges.
Dave
Please be positive and constructive with your questions and comments.