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Using Arduino => Microcontrollers => Topic started by: ProgrammerID on Apr 23, 2019, 06:24 pm

Title: Power Bank that supplies 5V to a circuit
Post by: ProgrammerID on Apr 23, 2019, 06:24 pm
I have a voltage regulator to 3.3V that feeds a circuit with a PIC and a LoRa Module, the circuit transmits for 10 seconds and remains sleep for 5min, has a total current consumption of 16mAh. If the circuit is powered from the USB port of the PC it works continuously, but if I connect it to a Power Bank it only works the first 5 minutes. What can I do so that the Power Bank does not shut down?

Thanks and Regards
Title: Re: Power Bank that supplies 5V to a circuit
Post by: spycatcher2k on Apr 23, 2019, 06:58 pm
Does this look like a PIC forum? Look at your address bar, forum.arduino.cc NO mention of PIC there!
Title: Re: Power Bank that supplies 5V to a circuit
Post by: ProgrammerID on Apr 23, 2019, 07:49 pm
I mean the Arduino Controller, the ATMGE328P to be more specific.

Thanks and Regards
Title: Re: Power Bank that supplies 5V to a circuit
Post by: Paul_KD7HB on Apr 23, 2019, 08:18 pm
I have a voltage regulator to 3.3V that feeds a circuit with a PIC and a LoRa Module, the circuit transmits for 10 seconds and remains sleep for 5min, has a total current consumption of 16mAh. If the circuit is powered from the USB port of the PC it works continuously, but if I connect it to a Power Bank it only works the first 5 minutes. What can I do so that the Power Bank does not shut down?

Thanks and Regards
The specification of your power bank should show the minimum load needed to keep the thing supplying power. Use that spec to pick a resistor to maintain that load.

Paul
Title: Re: Power Bank that supplies 5V to a circuit
Post by: DrAzzy on Apr 24, 2019, 03:11 am
Can you name an example of ANY power bank that spec's the minimum current before it shuts off?

I do not think I have ever seen that specified.

Apparently it usually works based on peak current, rather than average; a common technique I've seen is pulsing the dummy load every few minutes, for like a few milliseconds at a time. This is an issue that lots of people have wrestled with and there's a lot written on it. A bit of time with google will find info on what other people do about this.


Also 16mAh is not an amount of current. Current is measured in mA. Capacity of a battery is measured in mAh (milliamp hours, ie, a "100mAh" battery could supply a 10mA load for 10 hours, or a 100mA load for 1 hour).
Title: Re: Power Bank that supplies 5V to a circuit
Post by: 6v6gt on Apr 24, 2019, 09:25 am
Power bank auto shutdown suppression is discussed here:
https://forum.arduino.cc/index.php?topic=497195.0 (https://forum.arduino.cc/index.php?topic=497195.0)
Title: Re: Power Bank that supplies 5V to a circuit
Post by: abundanceapp on Apr 24, 2019, 12:46 pm
Thanks for share
Title: Re: Power Bank that supplies 5V to a circuit
Post by: ProgrammerID on Apr 24, 2019, 06:05 pm
I have read the information of the shared leagues, in fact the solution of all is to increase the energy consumption to reach a minimum of approximately 50 mA so that the battery does not turn off.

The solution that I look for is how to work with a power bank without it being turned off with a circuit that currently consumes 16 mA and later is 5 mA and even 1 mA if I activate the sleep mode.


Thanks and Regards
Title: Re: Power Bank that supplies 5V to a circuit
Post by: 6v6gt on Apr 24, 2019, 06:18 pm
Well, if you could put a 100 ohm resistor across the output of the power bank to create a 50mA load (Ohms law). There is then not much point in activating sleep mode in your Arduino, if that was seen as an energy saving measure.
You may find that there are more efficient ways of preventing the power bank doing a shutdown.
Title: Re: Power Bank that supplies 5V to a circuit
Post by: DrAzzy on Apr 24, 2019, 08:39 pm
Well, if you could put a 100 ohm resistor across the output of the power bank to create a 50mA load (Ohms law). There is then not much point in activating sleep mode in your Arduino, if that was seen as an energy saving measure.
You may find that there are more efficient ways of preventing the power bank doing a shutdown.
What you usually do in a case like this is switch that dummy load with a MOSFET, and pulse it on briefly every time you wake up (and use the WDT to wake every 8 seconds for this purpose) - in the vast majority of things with autoshutoff, a brief pulse of the load periodically is enough to keep them awake.
Title: Re: Power Bank that supplies 5V to a circuit
Post by: 6v6gt on Apr 24, 2019, 10:05 pm
What you usually do in a case like this is switch that dummy load with a MOSFET, and pulse it on briefly every time you wake up (and use the WDT to wake every 8 seconds for this purpose) - in the vast majority of things with autoshutoff, a brief pulse of the load periodically is enough to keep them awake.
Exactly. Post #6 and #9 here https://forum.arduino.cc/index.php?topic=497195.0 (https://forum.arduino.cc/index.php?topic=497195.0) go in this direction, but it requires some experiment with the specific power bank to minimise the wasted energy.
Title: Re: Power Bank that supplies 5V to a circuit
Post by: ProgrammerID on Apr 24, 2019, 11:09 pm
If I connect the ATMEGA328P with all the circuitry directly to the batteries 18650 of the power bank it works for about 7 days, but if I connect it to the USB port of the Power Bank it shuts down in 3 minutes. Is there any way to omit this "Savings Mode" in the Power Bank?

Thanks and Regards
Title: Re: Power Bank that supplies 5V to a circuit
Post by: DrAzzy on Apr 24, 2019, 11:34 pm
If I connect the ATMEGA328P with all the circuitry directly to the batteries 18650 of the power bank it works for about 7 days, but if I connect it to the USB port of the Power Bank it shuts down in 3 minutes. Is there any way to omit this "Savings Mode" in the Power Bank?

Thanks and Regards
Yes, we have already answered this question - repeatedly - above. Please read our replies, you've been given at least one solution as well as several links to threads or sites with additional information. And as I said, just searching google for this will give tons of results as well, as this is a common problem that lots of people have grappled with and found solutions for.
Title: Re: Power Bank that supplies 5V to a circuit
Post by: 6v6gt on Apr 24, 2019, 11:56 pm
And if you are struggling to find a Google search phrase for your problem, try:
https://www.google.ch/search?q=power+bank+suppress+auto+shutdown (https://www.google.ch/search?q=power+bank+suppress+auto+shutdown)