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Topic: Is this AVR sleep code correct? (Read 2918 times) previous topic - next topic

DKWatson

Add load for the wake cycle.
How does the solar pack turn on otherwise? Seems a rather poor design if there is no capability to function without operator intervention. Maybe you should be designing a new solar battery pack?
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

Marciokoko

The solar charged battery pack ir normally turned on by pressing a button because its designed for charging mobiles.  But if I can turn it on and have it stay on then that wont be a problem. 

The problem is that if the nano itself wont draw enough power to keep it awake (thinking its constantly charging a mobile) then you are correct, I need to think of a new battery pack.  Or I could just build one, but I think it might be best to just take apart the existing one and try to remove that circuit which I understand is doable?  I mean remove the circuit responsible for turning off the battery pack. 

DKWatson

Everything is doable, but is it worth it? Hacking a perfectly good battery pack that otherwise does what it's supposed to is some thing that I would do, not recommend others to do. If the thing draws such little power, maybe a 3xAA battery solution? Who knows, that might be enough for years.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

Marciokoko

ok i just thought of something.  The motors are the ones that draw a lot of power when they operate, which is only at a certain interval.  I could run the mcu from AAs on sleep mode and the motors from the solar re-chargind battery pack.

Marciokoko

OK...back to square one.  I just let a dc motor run directly from the battery pack and it ran for 1.5 minutes.  So this seems to indicate that either:

1.  Not just a steady current but maybe a changing current circuit is responsible for powering down the battery pack.

2.  Or the only thing that can keep it awake is the led built into the battery pack, only problem is the led stopped working.

Any ideas? 

DKWatson

$64,000 question. Is this a battery pack or a charger?
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

Marciokoko

#36
Sep 07, 2018, 02:51 am Last Edit: Sep 07, 2018, 02:52 am by Marciokoko
Not sure what the difference is.  But I got a couple of them a while ago.  They look like this:

https://goo.gl/images/xq9Cfr

DKWatson

The difference is that a 'smart' charger relies on feedback from the device being charged to maintain CVCC. As the voltage on the charging device nears Vmax so the output from the charger reduces to a trickle until charging is complete and then automatically switches off. In the case we're dealing with here, the only device you've attached that keeps the charger 'alive' is your phone. The nano and the motor do not. It suggests that the charger is perhaps looking for something (in terms of feedback) that it gets from the phone but not the nano or motor. If, on the other hand, it were simply a battery pack, it should stay switched on as long as a load is detected, which it clearly does not.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

DKWatson

A little visit with Google -

Quote
Tcom 23000mAh Fast Charge

With intelligent control circuitry to protect short circuit, overcharge, over discharge and over-current

Automatic shutdown after 30 sec once the target device is loaded or no device is connected
Nice product specs, but nothing you want to hear.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

Marciokoko

Got it!  So it's shopping time

DKWatson

Take something with you to test it.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

Marciokoko

Well the thing is it'll have to be online.

DKWatson

In a case such as this, the cheaper options are likely to be what you're after. A simple battery pack with a solar charger attached. No room in the profit margin for advanced electronics. You may yet have to hack it though as many units will not accommodate discharge while charging. If your budget permits, there's a much more elaborate design involving two batteries, one charger and a switching circuit which can also be controlled by the nano.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

DKWatson

There's an interesting little device (Google 4056E) that could be hooked up to two separate banks of batteries. With your current draw you could probably use 2x2 LIR2032. Every time you wake up switch power for the nano from one bank to the other and the charger to the unused bank.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

DKWatson

Another read for those sleepless nights.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mahatma Gandhi

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